Forestry Commission ARCHIVE FORESTRY COMMISSION

HISTORY

of

THETFOED, KING’S. SWAFFHAM, FORESTS

1923 - 1951

EAST (ENGLAND) - CONSERVANCY HISTORY OF THETFORD, KING'S AND SWAFFHAM FORESTS

CONTENTS

Page

CHAIRMAN'S COMMENTS 1

COMMENTS BY STATE FORESTS OFFICER 6

GENERAL DESCRIPTION OF THE FORESTS 7

Situation 7

Area and Former Utilisation 8

Present Utilisation 11

Physiography 13

Geology and Soils 14

Vegetation 15

Meteorology 16

Risks. Fire, insects, fungi, mammals, birds trespass 16

Roads 23

Labour 24

SILVICULTURE 24

Preparation of Ground 25

Choice of Species 26

Early years 26

More recent developments ...... 27

Planting ...... 30

Spacing and type of plants used 30

Method of planting ...... 31

Annual rate of planting ...... 31

Manuring ...... 32

Success or otherwise of Establishment 32

Natural regeneration ...... 32

Ploughing 33

Beating Up 34

Weeding 35

Mixtures 35

Rates of Growth 36 Page

Past Treatment of Established Plantations) ) 37 Brashing, pruning, thinning )

Nurseries ... 39

Research - Note by Research Branch 40

Conclusions ... 57

APPENDICES I - Notes from Inspection Reports 62

Thetford Chase 66

King's 77

Swaffham 80

II Record of Supervisory staff 86

III Rainfall and Sunshine data 88

IV Age/ Height Graphs for )

Scots pine

Corsican pine

European larch 90 et seq

Douglas fir

Oak

Beech

Map of the Forests

r HISTORY OF THETFORD, KING’S AND SWAFFHAM FORESTS

CHAIRMAN'S COMMENTS

It t o s well known before the establishment of the Forestry Commission

in 1919 that there were in East Anglia and particularly in Breckland large

areas of heath land suitable for afforestation. There was a party of

girls engaged at one stage of the 1914-18 war in collecting data as to the

growth of timber and I remember being greatly impressed on the occasion of

a visit to the party at Barton Mills with the large possibilities. The party must have secured a great deal of useful information not only on

growth but on such things as butt rot in spruce and larch.

The first acquisition was in 1922, a relatively small one at Swaffham,

to be followed almost immediately at Thetford by Elveden 3>159 acres and

Downham Hall 5>000 acres. The stage was set therefore for large annual planting programmes and afforestation was apparently a simple straight­ forward matter. In a private note, which I made after an inspection in

April 1924, I have extracted the following: Total area approximately 11,000

acres, of which upwards of 10,000 are available for afforestation and 2,000

acres have already been planted or sown. Bulk of planting with Scots pine,

only a small proportion Corsican "This is a pity and every effort should be made to reverse the proportions"; sowings 2 years earlier with Scots and

Corsican probably 50$ success but not yet certain; previous year's large

scale sowing failed; poplar's used as fire breaks making fair start but

some deer damage; nurseries not well-equipped; no rabbit damage seen;

importance of protection with a 6-point programme; outline of working plan

including use of beech up to 10$ by area as fire breaks; suggested rate of afforestation 800 acres per annum to begin with.

The Conservancy history suggests that the use of Corsican pine was restricted owing to fear of frost. This was not so; only later did we begin to learn about the incidence of frost and the importance of the micro- topography. There was good evidence at Icker buildings and on our Elveden ground (now sample plots E.179 and E.181 respectively) that Corsican grew much quicker than Scots. The real reasons for planting the latter in what I believed to be great excess were: prejudice against Corsican timber (in which prominent timber merchants shared) and greater ease in raising and

1 establishing Scots.

The next noteworthy silvicultural operation was the planting in P. 26 of no less than 749 acres on Elveden (Thetford Warren) with 50$ beech

(l yr. 1 yr. )and 50$ European larch or Corsican, followed by 775 acres of a similar beech/larch mixture in various parts of the forest. This ill- advised work, 7/hich was of a kind quite outside the experience of those in charge, resulted in great disappointment and considerable expense in beating up. It was not until 1936, when we enclosed part of the area in the so- called "Deer Pen11 (Compartments 113 and 114) and could make observations under controlled conditions that the silviculture of the establishment of beech in this environment began to be appreciated. Incidentally this is an interesting example of a simple experiment settling a considerable controversy. There had been much talk of the reasons for widespread failure of the beech - soil, moisture conditions, grazing by deer, rabbits and hares being individually blamed.

In the early pine plantations in East Anglia (Rendlesham was also an example) a great deal of damage was done by the Pine Shoot Moth. Scots pine suffered worst but Corsican hardly at all. At one time it appeared that large areas might be completely ruined but after a few years the incidence of attack was greatly reduced. The reason was never explained, but presumably there was set up a biological control which was ineffective at first. This Tortrix led to so-called "pre-thinning", to which reference is made later.

The only other insect which worried me was the Pine Aphis Lachnis which (especially at Rendlesham) looked ugly, but it too came under natural control. Pine Saw-fly, though very numerous from time to time was left to take its short course, and Pine Shoot Beetles, as we knew from experience in New Forest sifter the heavy fellings of 1914-18, could easily be combated by simple trapping methods.

The next development was the brashing of 3 or more rows of ride-side pines as a fire protection measure. I started this (in 1934) at Rendleshen in a plantation a little older than anything at Thetford. Three of us using saws made excellent progress and, because the day was wet, we were able to burn up the branches completely without any risk. Subsequent progress with this work was too slow and I had to call for periodic 2 reports.

In 1937 Mr. Connell, the local forester and I examined the oldest

plantations at Swaffham which had been badly attacked by Tortrix. We

concluded that it was important to get out the roughest of the trees and

made what came to be called a "pre-thinning." The breaks in the canopy

seemed large at the time but on revisiting the area after a lapse of years

I have been unable to find the places where trees were felled. Undoubtedly

this was a salutary measure but it had one unexpected result. Fomes

annosus developed from a few of the stumps. It is fortunate that Tortrix

attacks did not persist and pre-thinning became unnecessary in subsequent

plantations.

The Fomes problem is dealt with in the Conservancy description. At

one time it looked very alarming, but I gather that Fomes becomes less

destructive as the trees get older. Corsican pine seems more resistant

than Scots.

The question of fire protection became more and more pressing as the young plantations got into the thicket stage and I became more and more nervous as the prospect of war and enemy bombing increased. A large fire

in Culbin plantations in June, 1939, where the general conditions were

somewhat similar demonstrated the impotence of current fire-fighting methods

* and the necessity of making systematic use of water.

In 1938 Major Morris, Chief of the London Fire Brigade, at my invita­ tion accompanied me to Rendlesham where the fire hazards were even greater

than at Thetford, Some of the compartments were up to 60 acres in extent, unbrashed, and with no internal accesses. It seemed to me that not only would the control of fires in such areas be beyond our powers, but further

that fire-fighters might get trapped in the event of a large fire. Major

Morris was impressed with the hazards but could make no firm proposals on

the subject, which he said was outside his own experience and that of urban fire brigades. After that inspection I came to the conclusion that in the

event of war we would be lucky not to lose more than half our East Anglian plantations.

However, steps were taken to break up the plantations into smaller fire protection units and to develop fire-fighting equipment. A careful description of the work done would add greatly to the Thetford History.

3 So fair as I recollect the only direct fire attack by the enemy was on

Rendlesham (August 1940) when a great number of incendiary bombs were dropped on the plantations. Thanks to the precautions taken and the courage and devotion of Forester Brooks and his wife and the forest workmen, the total loss v/as some 6 acres.

In the event, also, war losses at Thetford were relatively small notwithstanding the presence of enemy planes over East Anglia on very numerous occasions.

From our side numerous proposals were made by various authorities independently for burning up the Black Forest and other German forests, and some of them were attempted, though I believe that the measure of success was small. Evidently the Germans, like ourselves, had taken pre­ cautions which were not wholly ineffective. All this in a sense was an encouragement in showing that under normal circumstanoes the provision of adequate fire protection need not be a hopeless proposition.

The large fire of 1946 (some 225 acres) was a foolish and wholly regrettable affair. I investigated the circumstances personally and came to the conclusions that it should not have occurred and that there were present ample equipment and man-power to suppress it in the early stages.

As a result the officer held to be responsible was dismissed the service of the Commission.

As regards King1s Forest the most interesting silvicultural work was perhaps the planting of Queen Mary's Avenue, which was commenced in 1936.

In this a mixture of birch and beech was used for the first time. The ground was deeply sub-soiled in the rows and selected beech transplants planted. The trees grew from the start, the birch growing the quicker and performing the desired funotion of nursing the beech. Only that part of the avenue nearest the commemorative stone could be excluded from the manoeuvres of tanks; the remainder was over-run and also grazed unmerci­ fully by thousands of rabbits. Apparently all that was left were a few birch and the dead sticks of a proportion of the beech. One or two very small enclosures were made in 1944 and very unexpectedly a number of the dead beech shot from the root and began to grow again. This tenacity of life and power of recovery in the face of very unfavourable conditions is an important factor in the silviculture of beech.

4 The Future of the Forests

The figures of growth quoted in the history bear out what I have always suspected: that the early rapid growth of Scots pine may not be maintained. Data collected in 1917 and published in Bulletin X indicated that on these sands overlying chalk the younger woods tended to fall into

Quality Class I (60 ft.) and the older into Quality Class II (50 ft.).

It is possible therefore that the rotation will be somewhat long for conifers and the production correspondingly low.

Apart from rate of growth I have come to regard Scots pine in pure stands as probably a temporary or pioneer type on the greater part of the area and especially where chalk is near the surface. The obvious sucoessor there is beech in respect of which there is a fair amount of production data. It may be that red oak will prove useful but it has first to go through the experimental stage. The common oak should grow reasonably well on selected sites but the mere fact that it springs up naturally with planted Scots pine is not sufficient warrant for large scale planting. I think Corsican pine will maintain its position as the highest timber producer because I am not quite happy about Douglas in which I have seen examples of bad root rot. Scots pine will probably regenerate so freely as to be a nuisance in places where Corsican would do better, while

Corsican itself will fail to regenerate freely enough to obviate replanting.

Whatever the precise course of events may be I think that the forest of the future will be more diversified owing to the presence of a greater proportion of hardwoods and to the breaking up of the present great blocks of a single age class.

R.

22/13/51

5 STATE FORESTS OFFICER’S COMMENTS

For purposes of recording historical notes on the evolution and

development of the ahove forest areas, they have been grouped into one

report as conditions existing on the ground and the forest technique

practiced in all three units have been comparable. As far as possible,

however, acreages have been listed separately and totalled in order that

these historical notes can be separated if required for the individual

forest concerned.

The area of forest under review amounts to 90 square miles approxim­

ately and, as such, represents the largest aggregate of forest in Great

Britain today and many of the problems involved in its development and

planning relate almost as much to rural administration as to silvicultural

technique. These areas form the nearest approach in Great Britain to

the large forest tracts on the continent and a somewhat different approach must be made compared with that of the normal, so called, forests in this

country which are, in fact, merely the woodland areas of old estates,

rarely representing an extent of over 5>000 or 6,000 acres.

(G. F. Ballance)

Divisional Officer

for Conservator.

27/10/51

6 HISTORY OF THETFORD CHASE. THE KING'S AND SWAFFHAM FORESTS

GENERAL DESCRIPTION OF THE FORESTS

Situation

The forests of Thetford Chase, The King's, and Swaffham, lie on the

western side of the counties of Norfolk and Suffolk, the county boundary

traversing the forest.

This area has been known for many centuries as The Brecklands and was

previously a sparsely populated region surrounded by a chain of small market towns, such as Thetford, Watton, Swaffham, Methwold, in Norfolk,

and Brandon, Bury, and Ixworth, in Suffolk.

The largest of these towns in close proximity to the forest area is

that of Thetford which dates from Saxon or earlier times and was once the

seat of a Bishopric* Many of the old local names surrounding the town of

Thetford had ties with it and provided open hunting country:- the local name of Thetford Chase indicates this and covered an indeterminate area in the vicinity of the town and was considered appropriate for the main forest block.

Swaffham Forest derives its name from that of the small market town which it surrounds on an arc from south east to north.

The King's Forest, which is in reality an outlier to the south of

Thetford Chase area proper and some four miles north of the town of Bury-St.

Edmunds, was given this name in commemoration of King George V's Silver

Jubilee in 1935 when the land was first acquired for afforestation. As a

further commemorative naming the old Icknield Way, which traverses this forest was partly planted, and is to be completed, as an avenue to be called

Queen Mary's Avenue.

Swaffham Forest extends to over 3»000 acres and King's Forest, extend­ ing to just under 6,000 acres, are administered as separate units, but the

Thetford Chase area proper, which extends to some 48,000 acres is broken down into 14 separate Beats for local administrative purposes. Nine of these Bests comprise the main block and the remainder are, more-or-less, outliers on the north and east sides with one to the south west.

The names of the separate Beats of Thetford Chase Forest are as follows 7 Cranwich Hockham

Croxton Lynford

Didlington Mildenhall

Downham Methwold

Elvedon Santon

Harling West Tofts

High Lodge

Area and Utilisation

The acreage under review in the present record is made up as follows:-

Thetford Chase Forest 48,353 acres

King's Forest 5 >933 acres

Swaffham Forest 3 >814 acres

A schedule of acquisitions of the provisional allocation of land indicated from the acquisition reports is outlined on the accompanying

Table I.

Going back into historical times, the area was farmed for sheep grazing in the Middle Ages and for several centuries thereafter, at the time when the rural population of Norfolk and Suffolk was higher.

8 Towards the middle and end of the last century, with the decline in

sheep fanning following developments in this type of farming in the

Dominions, the area reverted to heath and waste land but still maintained

a high sporting value and many of the old estates which covered the area

prior to the Forestry Commission's activities maintained themselves largely

on their sporting value.

Prior to afforestation large areas were covered by shifting sand dunes,

one or two small patches of which remain on land outside, but adjacent to,

Forestry Commission Woods. History relates that in earlier times the small

Church of Santon, lying at present in the heart of the forest, was more than

once drifted up by moving sands.

Subsequent to the sheep grazing activities the area became largely

depopulated, apart from a few game-keepers and rabbit catchers. There was, however, a small industry in the form of flint knapping in the village of

Brandon.

In the eastern outliers where the soil is a little heavier and more

stable, arable farming of a more static nature was developed but, with the

decline in agriculture following the 1914/1918 war, many of these farms proved too poor to operate on an economic basis on the then applicable agricultural technique.

Evidence exists that the Thetford Chase area was populated in pre­ historic times and remains exist of old flint mining activities in and around Grimes Graves in the heart of the forest.

Recent excavations near the town of Thetford indicate smelting and pottery industries of Romano-British and Saxon origin and evidence has come to light of early efforts at the glazing of pottery not hitherto related to that period.

I

9 Forest H istories TABLE X. Allocation of Land at Acquisition Thetford. Swaffham and Kings. § fi* § I & U ul. d i *d •H h l—l ■4 -3 3 frH ■P P 5 u a> d C « « C 3 § 6 d -I i- cd O 2 2 &§ r -P si •S' ■3 a- a? ’ s H fi £ n *rln ft & Q d O g a S O

H A- M Nrt O?H H ? H CM KNCO VO O t CM oO KN-d r m •A r- N K KN VO KNVO O O J 0 - ( n i 4 ^ ( NO ONCM O N ON K ON H N K CM s J KNKN rH M M . . CM CM I 3*= > • > v d bOP I N N f on cm ft O ^ O o8 £ J

on n h kn a a -a §g>g :'.s«. r—m -mm n- — m r vo vo CM CM CM CM o mi-i o £ ♦rt *H w *ti d 3 a1 a- ft p ft p B P w P M B s i — 1*I —0)fi I d r - i d 1 i -I O IO i- > + d *> © a 3 0 )- , >4 >« H *H xi a) o .d SsHS, ® oo S cm d h d d o n u

bp O 43 vo Is- Is- vo n u n k M CO p o cm 00 vo r$vo O H (O H H H co W co H H (OH H O r$vo vo mo mr- o mr- mo co*nin -d CMLT\CO min O C MO N > 7 V O C O VO O Om N mOOOOCMCMKNj-VDON m n k n k n k n k n k n k n k n k n k n cm k M C HH CM CM H m H H H CM CM i H2Ti « £ B • d »HH '? S p ■p i f . O a O d V e s c s p *

cm -*■ co-d- 33 o o c m vo h r-vo „ O* P O P O O*H £ d i n t o 4 vo vo 4 o t n i N CMvo KN H «—• r ’ - T « P o g u bo a> • £ -p knvo r-} kn J- J- . feOSEH

5 +> to d +» *H H o\ o - r &£ m g Cl I 0 •H 0 3 rl 3 CO -p « ON O £1. i313 on 3 3 H CM O h hi s ^ 5 a o l°i ai M cm — &■ — 3 K 8 ’3 J

CO H CM ON CM CM H S H p P df t df t f t p O 8 «t 4> s- w v v D p O S i p O . k d . H .fi d d d d d d d V i f d d d d h d d 0 naHhnMadoHhot 0 ) 0 lk o •y ii > I r nil n Atirlig in n m p irl ^ Mr- r CM N K i fid fi G = °S c .

NC -*-i-vo mm m o v if- - * - CM ON m CM H l - r H JL #

M N K CM H S 5 3 8 ■ ft i d fi /o CM ON rH CM CM 00 - r m m ON KN CM ON JL , 3 O M d c CM CO " 3 S M N K N K N K CM <2 > 2 o c « *ri fi fi *ri« on h H £ t d

S £ l r £ -d- d fi #

6,20? o i—i Existing Utilization of Land •d •H rH •H -p • P •p PM -p -P H h 5 c c (30 c hfl 3 G ta c 9 o d a) m Unplantable PH •H rH $ •iH si u © 03 b © 0)

Formed 1 Blanks 1 Burnt Other 1 i f * P o m • Acquired • after Areas land No. of Hand land felling Tenan­ cies oo NO -d K o\ i—1ON ON CM r- ON ON CM -d ON ON ON CM rH -d- ON £ ON KN o i a •k #k Thetford 1,828 •k 1,001 5,682 ON ON KN CM CD on ON r*- O UN CM CM KN CM 3 rH 1 1 1 1 i •» King’s #k •k 826 86 _ off _ VO VO 00 CO 00 3 rH 3 -d KN CM rH KN K\ KN O kn 1 i 1 •k Swaffham •k 23 106 ■ tn VO VO VO OO ON 00 00 ON ON rH r- ON ON CM O ON CM kn kn ON o CM KN O ON CVJLfN KN ON ON o i «k •k •k •k •k TOTALS 2,810 81 r» Present Utilization

(a) Sporting

Despite the advent of plantations, the sporting values of the land have been very largely maintained and, in fact, many owners have leased or conveyed land to the Forestry Comnission in order that the sporting interests can be kept up without the expense to the owner who has been able to lease land back from the Comnission for sporting purposes or, at least, maintain these assets on his adjoining agricultural land.

(b) Sheep Stocks

These are not now maintained on the area either by farmers or by the

Commission, although a small number of sheep may be found from time to time where they occupy accommodation grazing.

(c) Methods of Farming

With the mechanisation of agriculture and improved technique during, and since, the war, much of the land that was unplanted in pre-war years and then considered sub-marginal for agricultural purposes, is now reason­ ably productive, the main type of farming being arable with a high proportion of sugar beet.

As planting proceeded, the areas of better land were the last to be dealt with, with the result that at the end of the last war these areas had either been taken over by the Agricultural Executive Committees or they had directed the cropping of them and, in consultation with the

Ministry of Agriculture, some fairly extensive areas of old agricultural land have been transferred to the Ministry on a more-or-less permanent basis. These farm areas although in some places forming awkward enclaves into the forest lands do, in others, provide a useful measure of fire protection.

12 Little Ouse is the largest and upstream, to the east of Thetford town, divides into The Little Ouse proper and the Thet.

(b) Elevations

Elevations vary from about 20 ft. above sea level on the western side where the area joins the Fens to a maximum of 180 ft., the greater part of the forest lying between 50 and 150 ft. above sea level.

Slopes are negligible and the undulations only perceptible on account of the prevailing flatness of the country.

(c) Aspect and Exposure - LAr

The area has an all round aspect and is exposed in the main to the north and east.

Geology and Soils

The older geological formations consist of glacial, deposits, principally chalky boulder clay overlying chalk. More recently there has been a considerable deposition of sand, the depths of which appear to vary in many canes as a result of wind blow. Sand occurs generally as a surface soil over the whole area with a depth ranging from a few inches to thirty or more feet and, as with most riverain or glacial deposits there is a great variety in the amount and type of material deposited.

The soil is essentially dry as percolation takes place to at least the level of the clay below the chalk, whence wet weather chalk springs occur to feed the rivers.

The soils are generally sandy and variations are only due to their depth above the chalk and their topographical position; sandy loams containing a good proportion of humus are found mainly in the areas adjoining the rivers and, to a lesser extent, on old woodland sites.

14 The sands are, on the -whole, 'hungry1 and humus decomposes rapidly although with the more suitable influences of woodland conditions a true brown earth forest soil is likely to be developed in many places where the chalk is less than some five to six feet deep.

Where the sand overlying the chalk is deeper the soil is, on the whole, structureless although podsols occur at Brandon Park and Roudham where conditions more nearly comparable to true heathland have existed for several hundred years.

Vegetation

A number of vegetation types may be distinguished on the areas under review and these are as follows

(a) Grass heath type - Agrostis oanina. Agrostis alba. Festuca

ovina (the latter is commoner where chalk is near the

surface).

(b) Carex arenaria - dominant on drifted sand areas.

(c) Bracken (Pteris aouilina) - widespread over well drained

areas.

(d) Calluna - on podsols and poorly drained sites.

(e) Old hardwood areas - willow herb, nettle, woodspurge,

snowberiy.

(f) Lichens - local areas of blown sand with slight vegetation

only (Cladonia species and moss).

(g) Old arable or pasture - Seneoio and other weeds.

(h) Marshy river sites - Phragmites. Juncus species, Salix, etc.

15 Of the foregoing types those referred to as (a) and (b) represent some 70$ of the area, the remaining types being more-or-less distributed over the balance.

On the ■whole the vegetation is indicative of conditions suitable for afforestation and subsequent satisfactory tree growth, subject to a suit­ able choice of species and applied silvicultural technique.

Meteorology

The climate is, on the whole, the nearest approach that can be found in Great Britain to the true continental type where the rainfall is low and normally confined to the autumn and winter months. The annual rainfall is in the region of 24 in. but varies between about 18 in. to the high figure of 31 in. recorded in 1950.

Protracted periods of cold dry winds are experienced from the north and east in the spring and early summer with consequential droughts.

Frosts have been recorded in every month of the year but are severe in their effect on young plantations in the late spring and early summer.

Protracted periods of frost can be experienced through the winter months.

The snow fall can be frequent in winter although not normally heavy and drifting is not a usual feature.

Winds may be persistent and strong, particularly from the north and east during the winter months but severe gales and gale damage are seldom experienced.

Risks

(a) Fire

Fires have always provided a large problem in the Thetford area of

16 such vast coniferous plantations. The position is aggravated by the dryness of the climate and the rather strong winds, especially in the spring, in

this part of East Anglia and the railway lines which pass through the forest

Principal measures during the early years were the planting of belts

of broadleaved species, the cultivation of rides and railway sides and the patrolling of the railway line during danger periods. Roads were later

constructed in the forest by Ministry of Labour trainee workers and screefed fire lines with banks were formed by the same labour. The fire lines proved rather unsatisfactory since they were fairly quickly overgrown with vegeta­ tion and in later years the banks thrown up on each side made extraction of produce more difficult.

Although look-out posts were already in existence the more modem type of fire tower, as used at present, was first erected in 1934 and others in

I938 making a total of four. These, together with a look-out box at Abbey

Heath, just north of the railway line, form the basis of the present day system of control. All fire towers are connected to the public telephone system.

Since the topography is relatively flat, access into the plantations

is made fairly easy. The first mobile fire fighting equipment was used in

Thetford in 1938 when small portable water containers and tool wagons were in use, in 1940 there was a further improvement when a lorry carrying a

500 gallon tank, pump and hoses etc. was introduced. The present strength of fire fighting equipment is five 500-gallon mobile tenders which work in co-operation with the County Fire Service and the R.A.F. Fire Service if the latter is required. Water is provided by a series of 5,000-gallon static water tanks situated approximately one mile apart throughout the forest. All the forest is accessible by fire routes which are clearly indicated by numbers on posts in the forest, and marked on the fire control map in the fire control centre at Santon Downham.

Despite the periodic occurrence of fires causing more or less severe damage the early years of afforestation in the Thetford area did not occasion full appreciation of the fire risk, as the planting programmes were so vastly in excess of anything that was burnt and in the first year or so the ground vegetation was not heavy due to the previous heavy grazing by rabbits. The full risk and danger of fire began to become apparent in

17 the years 1934-1936, and the then existing technique of extinguishing fires hy manual beating was seen to be insufficient to cope with a major confla­

gration. Early detection of fire was realised to be of paramount importance

and the first fire tower was erected in 1934 and others followed in 1938*

A general inspection and appreciation of the fire problem was made

in 1938 by the Chairman in company with Major Morris, the Chief of the

London Fire Brigade, but no readily available proposals were forthcoming which could be implemented. At the start of the war the Chairman expressed fears as to what might arise in the event of deliberate enemy incendiarism and in places through the Chase belts of some two chains in width were clear felled with a view to making fire breaks. Progress on this work, however, was slow and the anticipated incendiary action did not arise. From 1944

onwards most of these belts were replanted with oak and although in their present state they do not form a very stable fire break their value will increase as the years go by, and they should form really useful fire belts in the next rotation. A certain amount of natural regeneration of Scots pine has occurred in these belts, and will have to be removed in course of time to make them more fireproof.

Towards the end of the war it was seen that the unbrashed plantations which form the bulk of the afforested area represented a very severe hazard, particularly with the increasing number of workers and other persons operating in the forest, together with the much larger number of trippers, etc. moving through the area, and along the numerous main roads traversing the forest. Considerations were given to increasing the access through the forest for fire fighting vehicles, but there was only slow development until the large fire in the beginning of May 1946 when 243 acres were lost in one day.

Following this fire rapid and drastic re-organisation of fire access and fire fighting methods was put into effect, and in the ensuing post war years this has borne fruit in that no serious conflagration has arisen and although liras continue to occur in fairly large numbers they can be dealt with in an early stage. The post war fire organisation is based on rapid detection, mobilisation and access. At present there are five towers covering the area, with two more planned. These are on the G.P.O. tele­ phone and can be in immediate oonmunication with the control room at the forest headquarters in Santon Downham village. The control room is manned

18 by a duty District Officer, and Fire Warden, the latter is responsible for

ensuring a smooth flow of communications and turnout of a fire fighting

team, together with their training. The Duty Officer is responsible for

organising the rapid mobilisation of teams and turning out himself to

control any outbreak. Teams of workers and villagers are trained and are

available both during and after working hours, and a relatively high degree

of efficiency and speed have been achieved, partly through training and

partly through a competitive spirit.

Turning now to consider the aocess through the forest. A large number

(approximately 200) of selected rides, tracks and paths through the forest have been numbered as fire routes, and these are indicated on the ground by posts at their point of junction with existing County Council roads.

These fire routes form the backbone of fire access and are quoted in

instructions on mobilisation. A further breakdown within the forest is based on maintaining all compartment boundary rides passable for mechanic­

ally propelled vehicles, at least in sufficient width to allow the passage of a lorry. This work is helped considerably by the large extraction programme now going on. A number of additional rides of this type, i.e. f some 20 ft. - JO ft. wide, have been cut through plantations to break down the size of compartment blocks to between 20 and 30 acres. Originally some of the compartments were up to 60 acres in size.

Additional access is provided within a compartment by breaking down

the compartment into 3 acre blocks by means of felling one or two rows of

trees and cutting access racks some 15 ft. in width. These serve the dual purpose of fire access and extraction. Within the five acre blocks

extraction racks are cut every 50 or 60 yards and thus it is possible to get the fire tender to within some three hundred feet of any potential fire

in the most dangerous plantations. The full break down of access tracks

is not always put into practice in some of the hardwood areas.

(b) Insect Pests and Fungal Diseases

During the development of the forest a number of insect and fungal

attacks have occurred and these have occasionally reached serious propor­ tions. Some of the more interesting of these are listed below:-

19 (i) Pine Sawfly (Diprion pini)

This insect was first reported in Thetford in 1926-27 at

Downham Warren and Wangford. Serious attacks had been reported

before this at Rendlesham in eastern Suffolk. The attacks

appeared to be particularly severe on areas where heather was

dominant. A virulent disease attacked the sawfly at Rendlesham

and infected material was sent to Thetford where it is believed

to have had some effect. Although the attack was severe the

growth was not badly retarded since the leading shoots were not

apparently attacked. These attacks eventually died down and

the insect no longer gives any cause for alarm.

(ii) Pine Shoot Moth (Evetria buoliana)

During the early years severe attacks were made by this

moth on plantations of all ages, especially on poorer soils, and

gave rise to considerable concern. Attacks were noticed to be

less severe where the sawfly was present and Corsican pine also

appeared to be immune. The insect is still present on a smaller

scale, particularly at Mildenhall, where damage is still done.

It is believed that after the second thinning few of the planta­

tions will show any sign of the damage done by the moth as a result

of the removal of the damaged trees.

(iii) Pine Shoot Beetle (Myelophilus piniperda) and Pine Weevil

Following the felling of old woodlands and belts on

adjoining land these insects spread and began to attack the new

plantations. It was found possible to control these pests by

regular trapping, removal of produce, etc., and these precautions

are still in force today owing to the large thinning programme.

(iv) Pine Aphis (Adelges pini)

This insect was noticed in the early years of Thetford

Forest and sometimes attained large proportions. During 1SU3 it

was noted generally over Thetford Chase and caused considerable

browning and dying of needles with no apparent effect on the

plantations.

20 (v) Cockchafers (Fhyllopertha, Melolontha and Rhizotrogus)

In the nurseries cockchafer attack was prevalent from 1927 especially at Lynford. A vennoral injector was purchased in 1927 hut the injection of the soil with carbon disulphide was not a success. Decoy crops of lettuces were found to be the best method of withdrawing attacks from the nursery stocks. Nevertheless in

1930 serious losses were incurred at Lynford amounting to over a million one year beech and Corsican pine transplants. A census of chafer species by Mr. J.M. B. Brown in 1932 showed that Phyllopertha was most abundant with Melolontha and Rhizotrogus next respectively in quantity. The epidemic was not completely reduced to reasonable numbers until 1935.

Principal methods of control were trenching around sections, fallowing and deep ploughing. Very slight attacks have occurred in recent years in some of the older nurseries.

(vi) Fungi - Fomes annosus

As the younger plantations developed, patches of attack by

Fomes annosus were noticed in some areas. These were reported in Warren Wood in 1930. By 1935 the attack had spread to areas at Elveden, Downham and, Lynford and has now been reported on most units of the forest. It was at first thought to occur on old agricultural sites but it has subsequently been shown

(Dr. J. Bishbeth of Cambridge University) that it is most frequently found where the soil is more alkaline owing to the presence of chalk.

It is believed that fungi antagonistic to Fomes are not abundant in alkaline soils. Experiments by Dr. Rishbeth showed that the infec­ tion of stumps by Fomes may be reduced to 10$ - 15$ of the nonnal by painting or creosoting them immediately after felling whereas no protection was afforded by covering the soil. The present practice is to remove the infected stems and underplant with other species, such as beech, but the success of this method is still uncertain since there is a tendency for the underplanted beech to be attacked as well.

21 (c) Mammals

(i) Deer (Roe)

These were a source of worry in the early years causing

damage to plantations especially at Elveden and High Lodge.

Considerable numbers were killed but they continued to spread

further afield although a special deer-stalker was appointed.

At the present time a few deer are reported on all units and

these are kept down by shooting and snaring. Although at one

time the roe deer, only, appears to have been present, the red

deer is now reported from several units and the fallow is

present on Kings just south of Thetford forest.

(ii) Babbits

These have always been a major problem in the area since

it was infested with them before afforestation began. All the

normal precautions and methods of control are applied where

necessary. One of the main objects is to keep the rabbits out­

side the fence after the internal population has been exterminated.

Between the years 1930-35 much trouble was experienced when this

was not carried out and in obtaining amicable co-operation with

the sporting tenants who did not appreciate the importance of

rabbit extermination.

As an instance of the rabbit population, the Military took

over King's Forest in 1941 and from that time, until the area was

derequisitioned in 1947 and the rabbits subsequently cleared in

June, 1951, this area, of nearly 6,000 acres, which had been

cleared of rabbits at the time occupation commenced, was re­

populated to such an extent that when clearing was finally completed

nearly 77,000 rabbits had been caught.

(iii) Moles

Much damage was caused in 1926 by mole3, in the newly

planted areas, by their burrowing under the plants. Thi3

continued for several years and extensive trapping of moles

took place. Even at the present time moles occasionally cause

this type of damage on newly planted areas.

22 (iv) Squirrels

The red squirrel is the common squirrel and has to be kept

under control although no great damage has been caused in recent

years. There is, as yet, no record of any grey squirrels in the

forest.

(d) Game - Pheasants and Pigeons

Although very numerous these have not caused any appreciable damage to plantations but nurseries have been very seriously affected and strenuous

efforts have had to be made from time to time ■with scarers of various sorts

to reduce damage from the scraping of seed beds.

(e) Trespass

In a forest area of this extent trespass is bound to occur as the area

is covered by a very large number of public roads, rights of way, etc., and

the best method of combating this has been the gradual education of the

local population in the value of the forests with the result that, on the

whole, damage resulting from trespass has been very small.

Trespass resulting in fire is, of course, a constant source of danger

and can only be dealt with by careful fire watch and by propanganda.

Roads and Communications

Owing to the exceptionally level conditions obtaining in these forest

areas the matter of movement through the plantations and extraction does not

present very serious problems.

A number of main County Council roads traverse the forest area in all

directions and these are supplemented by metalled forest roads. The first

metalling of forest roads took place in 1935 and. 1936 when Ministry of

Labour trainees carried out small scale operations. Since the last war

road schemes have been expanded but metalled roads are only in being or

planned for fire protection and administrative purposes through the larger blocks of forest and along railway lines. Some thirty to thirtyfive miles

of metalled roads exist today and it is not anticipated that these will

extend beyond a total of fifty miles for the whole area.

Subsidiary comnunication and extraction can be achieved quite satis­

factorily on the normal surface of the soil and after a few loads have

traversed a route it is quite passable to normal motor traffic throughout

most of the year and tracks of this nature are being developed along all

compartment boundaries. 23 As a further breakdown, and in order to assist in fire protection, racks are cut through plantations to break these down into five acre blocks once they have become established and are in the thicket stage, and when extraction takes place one or two rows of trees are removed, every fifty or sixty yards, which allows the passage of lorries.

Labour

At the commencement of forest operations in the early 1920's, there was little or no labour available and certainly none with any real forest experience, although, with the agricultural depression existing at that time, a good type of rural worker was recruited to the Forestry Commission and these have formed the backbone of the forest staff.

In the 1920's, when private estates and their sporting interests were still a veiy large feature of the locality, a large number of men were employed part time but, since the last war, permanent regular employment has been available to all the workers that can be got hold of. At present some 500 men are employed on Thetford Chase Forest and a further 100 between

King's and Swaffham; this number, although 1% or Q% short of present day full requirements, is not likely to increase appreciably for the next few years.

The Forest Workers Holdings Scheme developed between 1928 and 1938 and did much to establish permanent labour strength in the forests but, with expanding post wax requirements, some 50 or 60 houses have been built mainly around the old nucleus village of Santon Downham, which is now developing into a large forest community.

Despite the reasonably satisfactory present day labour strength further houses will be required if workers axe to be settled permanently in forestry and many of the old houses taken over from the estates at the time of acquisition will have to be demolished or modernised.

Silviculture

Land has been acquired and planted since 1922, in which year the first plantings were carried out at Wangford, south of Brandon, where some 350 acres were planted, and on the Swaffham unit where just over 100 acres were planted.

24 The yearly rate of acquisition has varied considerably, the principal acquisitions occurring in 1924 when 10,000 acres were acquired and in 1930, when nearly 7,000 acres, were acquired. Acquisitions have continued up to pre-war time, the last big one to come in being that of Wretham, some 3>400 acres, in 1939. Between 1922 and 1924 nearly 1,800 acres were planted on

Thetford Forest and close on 600 at Swaffham.

Between 1924 and 1929 the rate of plantings increased, very considerably with acquisitions and an average of just under 3,000 acres per annum was carried out at Thetford and nearly 500 acres per annum at Swaffham.

At Thetford in 1930 the programme was greatly reduced owing to hiatus in the progress of acquisitions but mounted again between 1931 and 1935 to an average of nearly 1,800 acres per annum. At Swaffham Forest there, was a considerable fall off until 1936 and between then and the last war an average of about 170 acres a year were planted.

At King's Forest, which came in for the 1935/36 planting, little was done in the first year but thereafter the programme averaged about 500 acres a year until the beginning of the war, when the area was requisitioned in March 1941, as a Tank Training Area and remained under military occupa­ tion until 1945* During the four years of military occupation about 1,800 acres of plantations were either totally lost or very severely damaged with lesser damage to the remainder.

At the present time there are over 31>000 acres of plantations formed by the Forestry Commission on the Thetford Chase and some 3,100 acres at are Swaffham. At Kxng's Forest there/at present some 3,400 acres of planta­ tions. In addition there are some 2,500 acres of old acquired woodland, mainly strips and belts, planted in the early part of the last century for game cover.

Preparation of Ground

In the early days the vast areas of heathland planted

did not involve very great preparation except for ploughing,

which was carried out with single or double furrow agricultural

type ploughs by contractors.

The relatively small areas of old woodlands that were

replanted involved the clearing of bramble, bracken, snowberry

and a small amount of coppice, which was done by hand,

25 Ploughing methods are more fully described in the section

dealing with ploughing.

On the open heaths little or no coppice occurred as regrowth

and the Thetford Chase and adjoining units provided one of the

simplest afforestation problems, giving satisfactory results on

a large scale, that the Forestry Commission has so far tackled.

Virtually no draining was required, except in a few Bwamps

and carrs alongside the river banks. Fencing, however, was

necessary on all plantations and proceeded as a routine operation.

Choice of Species

(a) Early Years

V/hen the initial plantings were made the climate apparently dictated the choice of species. The principal species was Scots pine already known to be frost hardy and reasonably drought resistant from the evidence of older private plantations and hedgerows in the district. In 1923 direct sowings of Corsican and maritime pine were made on old arable grasses and heathland respectively. The sowings of Corsican pine were unsatisfactory, but the maritime pine was more successful although the latter subsequently showed a poor rate of survival. Some further plantations of Corsican pine were made in the early years but the planting of this species was carried out cautiously since it was suspected of being frost tender. It is possible that, owing to the large planting programmes involved, faulty weeding may have been an equally important factor as the cause of failure, since Corsican pine shows slow growth in its first few years. It was a practice during this early period to replant old woodland sites with conifers, and Douglas fir was frequently chosen for this purpose as at Santon Downham (P.25). These plantations suffered considerably from frost when young and were apt to be smothered by coppice regrowth, snowberiy, etc. Failed patches were beaten up with Scots pine and often the Douglas fir, aided by the Scots pine grew above the frost level and made a remarkable recovery. The Douglas fir are now growing satisfactorily over most of the older plantations.

In P.26 and 27 an attempt was made to introduce hardwoods into the forest. Approximately 1,600 acres were planted with beech using European larch and Corsican pine nurses in varying proportions. Some of these areas were ploughed before planting and others, such as Warren lodge, were

26 screefed. The sites chosen appear to have been those where the chalk was within two or three feet of the surface. By 1929 these plantings were

seen to be a failure in so far as they had shown little improvement on

their initial condition. The nurses had not provided sufficient protection

from frosts and, as was shown later, deer and rodents were an important

factor. It was decided that no additional large scale planting of beech would be carried out until further investigations had been made. A series

of experimental plots was set up at Elveden to compare various methods of

introducing beech with Scots pine nurses.

In 1927 a species experiment was set up in High Lodge Forest to

discover those species more suitable for planting on grass heathland. The

species planted were Scots pine, European larch, Douglas fir (green), pedunculate oak, red oak, sessile oak, beech, sycamore, Abies pectinata,

Cupressus macrocarpa. Thuya plicata. Chamaecyparis, lawsoniana. Pinus

strobus, Sequoia sempervirens, Pinus radiata and Abies nobilis. Of these

species only seven can be described as successful, these being Scots pine,

Corsican pine, Pinus contorta, Pinus ponderosa, European larch, Japanese

larch and Douglas fir (green).

In 1932 Scots pine was introduced as a nurse into half of each broad

leafed species plots to attempt to determine the extent to which frost was

responsible for the set back since damage by vermin was also severe.

Results of these experiments were rather inconclusive. During the early

years experiments were also tried in growing beech using sycamore as a

nurse.

(b) More Recent Developments

Since 1930 there has been a general increase in the proportion of

Corsican pine planted. Initially this increase was probably the result of

attacks on Scots pine by the pine shoot moth (Evetria buoliana) and

Myelophilus beetles. More recently the Scots pine has apparently proved

to be less frost tender than was originally thought and this, with the

superior growth of the early Corsican pine plantations has resulted in the policy to plant Corsican pine wherever possible in preference to Scots pine.

Earlier plantings of larch and spruce have indicated that these species will not normally produce sound timber at the main crop stage, and they

27 are therefore no longer planted for that purpose.

About 1536 it was noticed in the increased plantings of Corsican pine made in the early thirties that some of the plantations contained a very rough and heavily branched tree. A detailed investigation made in 1942 showed that considerable areas of this coarse "ursuline" type had been planted. The origin of the seed was traced, and the name "ursuline" is derived from this source. Steps were taken to control further supplies of this type.

Although oak was occasionally planted before 1930 large scale planting of this species was first undertaken in 1931 when Dr. Steven's method was adopted. In this method three oak to one Scots pine nurse were planted in lines, the nurses being 9 ft. apart and the oak 1 ft. 6 in. apart in between.

The Scots pine in the adjoining lines were staggered so that they formed diagonals across the plantation. The sites chosen were on the more fertile agricultural type soils. The original intention was to remove some of the pine when the oak reached 6 ft. - 9 ft. and replace with beech. Owing to labour shortage during the last war delay in removing the pine caused some concern but over most of the areas this has now been completed leaving a pure oak crop which appears to be quite satisfactory. At the present time attempts are being made to raise oak without the use of nurses since oak has been found to be reasonably frost hardy and with the increased shelter formed by the older plantations, conditions are now less severe than at the beginning of operations on the Chase when there was little or no shelter for young plantations.

The lack of success of the early beech plantations has already been mentioned. Attempts made during the thirties have been accompanied by greater success. In these later plantings European larch was usually employed as a nurse. It was found that until the larch were sufficiently large to shelter the beech the plantations made slow progress since both species suffered from frost and in some areas it was necessary to beat up with Scots pine. Since 1935 birch has been used in place of larch as a nurse for beech and has proved most successful. Birch has also replaced

Scots pine to a large extent as a nurse for oak in hardwood belts.

The beech in the older plantations with Scots pine and European larch nurses were still unsatisfactory and in 1936 in Compartments 203, 204 and

28 207 of High Lodge unit (comprising approximately 80 acres) a deer and rabbit

proof fence was erected since it was suspected that browsing was one of the

factors affecting the success of the beech. A similar small experiment was

carried out on a beech belt in Santon unit then part of Downham. Judicious

thinning and pruning in these enclosures has been carried out and the beech

have since made good progress. The beech outside the enclosure has also

shown some improvement but this did not compare with the improvement

inside and is believed to be connected with the general decrease in the

numbers of deer present and the increased shelter from the conifer. The

following table gives some idea of the improvement following fencing.

Corsican pine Beech Beech Year Average Height Average Height Maximum Height (feet) (feet) ffeet)

1936 10-15 (assumed) pJL -

1943 25 14 23

1947 33 17 33

1950 35 24 35

Just prior to the last war a number of acquired plantations were

underplanted with beech to provide an under storey and to fill in the gaps

in the main crop. These have proved very successful. This practice of

underplanting with beech has also been employed in the older pine planta­

tions formed by the Forestry Commission where loss by Femes annosus has

occurred. In some of the larger pine blocks work has commenced in breaking

these up by thinning strips 1^ chains in width and introducing belts of

beech.

From sin early stage hardwood belts have been formed along roadsides.

A number of hardwood species have been used in these belts and it is

possible that some of these, such as the American red oak (Quercus borealis) may eventually be planted in plantation.

There have been small areas of poplar in the moister river areas in

Thetford Chase for some years but, except in one or two cases, these have

not been very successful owing to the effects of canker. There are still

considerable areas available for planting but these have not been proceeded with in recent years pending investigation and production of canker free

strains. 29 Planting

(a) Spacing

The normal spacing applicable to the Thetford Chase as a whole, and to

other units dealt with, was 4? ft. and has remained as such except in respect

of the relatively small areas of larch and douglas which are at 5 ft. Oak, ; i when used in mixture with pine nurses, has frequently been planted in rows

of 4g ft. apart with the oak 2 ft. apart in the rows.

(b) Type of Plants Used, etc.

With a planting programme on the scale of that taking place on these

breckland forests, the very large number of plants required was produoed,

in the main, in nurseries on the Thetford Chase area but considerable imports

took place from time to time from all over the Kingdom.

It can be said that every age and size of plant of the speoies used has been tried on the Thetford Chase, often against the experience of the

officers concerned with the planting operations, but through force of

circumstances in implementing the National Forest policy and planting

programme. In the early years and between 1922 and 1932 many of the plants used were on the small side on account of the bare land conditions existing

at the time of planting. Seedlings have been tried extensively but have

never proved very satisfactory and after protracted study it is agreed that

with the pines, Scots and Corsican, 1 + 1 transplants, sturdy and well

rooted and of about 9 in. in height, provide the best stocks. Larger plants

or those of 2 + 1 and, very occasionally 1 + 2 age, can be used in some

reafforestation areas.

Plantings of Douglas fir and European larch again varied in type of

plant, European larch however has been abandoned and the Douglas fir now used, and which give the best results are plants between 12 in. - 15 in.

in height of 1 + 1 or 2 + 1 age.

With beech, many of the early failures are attributable to the small

size and weakness of the plants used and although today stocks of 2 + 1 and

2 + 2 are favoured, evidence indicates that even sturdier plants may well

be desirable.

With oak many of the early plantings carried out involved the use of very ancient transplants and it was only occasionally that seedlings of

reasonable size were used. These have invariably given better results

30 and todays practice requires the use of 1 + 0 or 2 + 0 seedlings of 10 in. in height or more.

(c) Methods of Planting

The practice as regards actual planting methods has varied very little since the earliest operations and normal procedure is for either a vertical notch or an 'L' notch to be cut in the line of the furrow: all planting is carried out in the bottom of the furrow owing to the dry conditions and the ploughing carried out is in the main a form of mechanical screefing of the top layers of the soil.

(d) Annual Rate of Planting

This followed very closely on the rate at which acquisitions took place. The tabular statement given below sets out the actual figures of acres planted each year.

TABLE III

Areas Planted, Thetford, Kings and Swaffham

P.Year Thetford Kings Swaffham Totals

22 313.6 108.4 422.0 23 509.3 - 348.4 857.7 24 733.9 - 233.4 967.3 25 1630.2 - 531.3 2161.5 26 3212.0 - 664.7 3876.7 27 3995.8 - 315 4310.8 28 3849.5 - - 3849.5 29 2339.3 -- 2339.3 30 1145.0 - 87.5 1232.5 31 2412.8 -- 2412.8 32 1856.6 - 55.7 1912.3 33 1592.2 - 19.3 1611.5 34 1390.9 -- 1390.9 35 1098.2 - 1.4 1099.6 36 619.2 637.5 124.4 1381.1 37 763.4 622.3 146.2 1531.9 38 588.1 89.1 188.1 865.3 39 645.7 160.3 192.6 998.6 40 383.1 422.1 - 805.2 41 870.8 322.2 - 1193 42 181.9 ■ ' - - ■ 181.9 43 200.7 - - 200.7 44 139.4 1 4.2 144.6 45 68.1 - - 68.1 46 130.3 . - - 130.3 47 441.8 - 53.8 495.6 48 577.8 762 T 1339.8 49 522.4 221.7 39.4 783.5 50 6067.8 134.2 18.1 6220.1

38279.8 3372.4 3131.9 44784.1

31 (e) Manuring

This.has been carried out on an experimental basis, particularly in the early years, but no large scale field manuring has been done since before the war.

(f) Success or otherwise of establishment

In reviewing the establishment and development of plantations over this large area at this stage, it is difficult to pick out any really extensive areas where plantations can be regarded as consistently poor.

Rate of growth and development varied very considerably from year to year but now that the bulk of the area is established and under a thinning programme, many of the early irregularities are evening out.

Corsican pine have, on the whole, taken longer to become established than Scots but once they have got a good hold have grown very much faster; many of the Scots plantations have been subject to Tortrix damage in their earlier years and are not today carrying the volume that is to be antici­ pated from more recent plantings.

Plantations of beech formed before the last war suffered considerably from rabbit, hare, and deer damage, with the result that many of the post war beech areas appear more thriving than the older ones.

Oak generally have grown well and establishment on such poor soil and site conditions is often earlier than might be expected although consider­ able losses have occurred as a result of frost damage in low lying ground.

Owing to the lack of records in the first decade of operations one cannot tell with certainty that plantations recorded as having been planted in any given year are, in fact, truly representative of that year’s work as intensive rabbit damage and unrecorded fires have frequently resulted in very heavy subsequent beating up, the plants used in this latter operation forming the present day group.

(g) Natural Regeneration

There is good evidence in Brandon Park that natural regeneration of

Scots pine can be obtained in the forest. Here, on a podsolised soil, very good plantations of natural Scots pine k3 years old have followed the seeding by parent trees of which several of good type remain. After the removal of Scots pine timber in Brandon Park during the second world

32 war about 30 acres has been successfully regenerated from the mother trees

left after felling. Seedlings of European larch are also to be found in

Brandon Park. Where rides were levelled for extraction and fire purposes

immediately after the war, Scots pine seedlings were later found in some

numbers and even on undisturbed rides natural pine can be found. Corsican

pine has also been noted on ride sides but not so frequently as Scots pine.

Scattered seedlings of oak are commonly found in the pine plantations

and in open hardwood plantations seedlings of oak, ash, sycamore, chestnut

and other hardwoods can be found. A good example of this type of natural

regeneration under hardwoods is provided by Thorpe Plantation in the Harling

area. The indications are that natural regeneration of hardwoods should

be obtainable if the correct conditions required can be ascertained.

Ploughing

The open heathlands dealt with presented little problems as regards

preparation prior to ploughing and the work involved comprised merely the

removal of occasional scrubby birch or deformed natural pine.

No records are available as to the date on which ploughing first

commenced but contract work with single and double furrow agricultural

type ploughs was carried out in the late 1920's. Ploughing was invariably

of a shallow nature to about five or six inches and involved mainly a

mechanical screefing of the top mat of grass and heathland vegetation.

In the late 1930's a plough was developed which cut two single

furrows at the required planting distance. It was constructed from a

cultivator frame fitted with two plough bodies and it proved a more

economic method of covering the large areas involved although it did not

give such satisfactory results in the more difficult areas where Carex

arenaria was predominant and hand screefing had to be resorted to.

At the beginning of the second world war a further type of planting plough was brought into use, this was developed from the Ransoms sub-

soiler frame attached to a single furrow, double breasted plough with

cutting discs. This enabled the turf to be cut and laid

33 on either side of the furrow resulting in an artificially created increased depth to the furrow and the shelter provided thereby was beneficial to early establishment. This plough is still in use and has been found to give the most satisfactory results but, as a post war development, a sub-soiler is attached to the back of the plough with a cutting depth of

18 in. to 2 ft. and this is used on all sites where pan or sub-soil compaction occurs. It has proved invaluable in the replanting of the war damaged areas in King's Forest which have been heavily consolidated by the constant passage of heavy military vehicles.

The present sub-soiling attachment is bolted or welded to the plough which has a very short beam, thus enabling the whole outfit to be tripped from the towing tractor. Efforts at sub-soiling the harder areas have been carried out since 1936 but, prior to the last war, the sub-soiler was either an additional independent attachment to the plough or was done as a completely separate operation.

No full ploughing has been carried out on these areas, neither has the stump jump plough been used in any reafforestation work, as the coppice regrowth and woodland vegetation has not been heavy except over very limited areas and the soil is of the uniform lightness described above.

Beating-Up

This operation was of necessity very heavy, particularly in the earlier years following rabbit damage to the original plantings but, until the late 1930's, it appears that in beating up the original species were used in almost every case, although, in some of the earliest plant­ ings of Douglas at Swaffham, Scots pine were used for beating up and had a beneficial nursing effect on the original crop, resulting today in mixed plantations.

The most interesting beating up operations have been carried out on the King's Forest, following the military damage, to Scots and Corsican pine plantations, in which Douglas fir have been used as the beating up species in the smaller gaps and beech in the larger. It is appreciated that in the areas treated in this manner an undue amount of plants have been!

34 used in certain places due to lack of experience as to the subsequent growth of the pines but it would appear that the principle is sound despite a number of losses from frost and drought.

Providing beating up is carried out within one or two years of the

initial planting it has been found that plants of the same type and size as the originals are quite suitable.

Since the early 1930's, when more Corsican was used in general over the area, beating up frequently took place with Scots pine owing to the non-availability of sufficient stocks of Corsican, in most cases however sufficient of the original species remain and have become established to form a final crop, the Scots being removed in early thinnings.

Weeding

Weeding is necessary on all young plantations for the first three or four years after planting and although in places heavy weeding is necessary it is all in soft vegetation. Following the disturbance of soil, resulting from ploughing, grass regrowth is very heavy and tends to choke the young trees unless they are allowed freedom to harden off in the autumn.

The amount of normal cleaning operations required in these areas is insignificant as the open heath does not encourage the growth of weed species, etc., which are likely to interfere with plantations once they are established.

Mixtures

Much of the work carried out in afforestation with mixtures has been more fully described in the sub-sections dealing with planting and choice of species above but am interesting development has occurred at the King's

Forest in particular, in relation to the establishment of the Queen Mary's

Avenue, where beech and birch were used in mixture, the latter as the nurse.

In a small area which was kept outside the wartime military requisitioning birch has proved to be a most successful nurse to beech and although the planting of this avenue was carried out with great deliberation and grew to an extent greater than came to be expected in normal field work, the general indication is that birch can be accepted as about the most success­ ful nurse for beech, although great care is required in the years following establishment to see that the beech are allowed sufficient freedom by the gradual removal of the birch. 35 Underplanting has been practiced since the middle 1930's, since when endeavours have been made to restock certain of the older acquired wood­ lands where the crop was open, by the introduction of beech. Results have on the whole been satisfactory although the lack of labour and attention which could be given to these areas during the war has resulted in a somewhat slow rate of development and, generally, the great difference in height between the young underplanted beech and the old mature timber does not give as satisfactory a result as would have occurred had this work been on a smaller scale and progressive over a longer period.

Rates of Growth

In an endeavour to obtain an adequate picture of the rates of growth of the several main species used in the afforestation of the breckland areas assessments were made by stem analysis of maximum, average and minimum, trees on each beat for each P. Year where a reasonable planting programme for that year had taken place. Data gathered included total height, quarter girth breast height, timber height to 3 in. timber and quarter girth at half timber height. From these figures the volume was computed. In addition the annual height growth in inches was recorded for each year subsequent to planting. In all, some 200 or more assessments were made, each giving a very complete picture of the progress of plantations and attached to this history as Appendix III is a set of these assessment forms selected as the most typical and instructive. They give figures for growth of the main

species at five year intervals. (N. B. full set of assessment forms are available but not included).

From these forms it will be seen that Scots pine have a more rapid growth in the early years of their life compared with Corsican but the Scots appear to reach a peak rate of growth between the 15th and 20th year and thereafter steadies down, whereas the Corsican, after a slower start, is more gradual in reaching a maximum rate of growth, which does not occur as a rule until after the 20th year.

European larch has been found to be more difficult to assess in its early growth but after the 20th year height growth becomes more and more restricted.

Douglas fir produces a much steadier growth than in the wetter parts of the country and does not reach its peak until after the 12th to 15th year.

36 Assessments in respect of oak indicate a very slow 3tart, although

rates of two to three feet are achieved about the 20th year.

Beech, again, has proved to be a very slow starter for the first four

or five years of its plantation life and not until it is well over 15 years

and firmly established does it produce any really appreciable growth.

Past Treatment of Established Plantations

(a) Brashing

Prior to the 1939 war brashing was not a normal forest practice and

indeed there were few enough plantations of adequate size in which to carry

out this operation but, of necessity, to allow access for marking thinnings

a proportion of the crop was brashed.

In post war years it has been found that brashing up to 6 ft. is a virtual necessity, both for fire protection purposes and for ease of marking and extraction of thinnings, and is normally carried out over the whole of

the area on a prescribed and controlled programme on piece-work rates of

from 6o/- to 75/- per acre.

(b) Pruning

Pruning is not normally carried out in young conifer plantations

although in selected elite stands high pruning of up to 150 stems per acre

of the best formed trees is carried out.

Pruning of poplar stands has been carried out in accordance with the

required technique although it has been a slow job to educate Foresters

and Foremen to the true value of this work.

(c) Thinninig

Very little thinning was undertaken in Forestry Commission plantations prior to 1939. In the earlier years the practice of "wolfing" or pre­ thinning was prevalent but during the war years it became necessary to adopt

a method which provided speed of production with a minimum of manpower and

supervision. A system of line thinning was therefore introduced by which

complete lines were removed in varying proportion, 1 in 3, 1 in 6, 2 in 12,

etc. Small areas of selective thinnings were also made.

Sample plots were started in 1939 when plots were set out in Forestry

Commission plantations of Corsican pine and Scots pine and the number of

these was increased in 1942.

37 In addition sample plots were set out in 1939 at Broomhouse and Methwold

(ickerbuildings) in acquired woodlands in Corsican pine plantations then

aged about 38 years.

After the second world war as labour and supervision became available

a large thinning programme was begun, many areas were already in arrears

with their thinning programme. The line thinning method was discontinued

and a selective system adopted. Two rows were also removed every 25-35

rows for extraction purposes. These also provide access to the plantations

in the event of fire. More recently, series of l/loth 311,3 V^Oth acre

sample plots have been set up in Corsican and Scots pine plantations to

facilitate the estimation of yields from first, second and third thinnings.

The thinning programme for the Thetford Chase Forest has increased

in post war years from some 3,000 acres to the present day figure of about

5.000 acres which, it is anticipated, will stay stationary for some four

or five years when it will greatly increase to absorb the youngest planta­

tions.

At Swaffham fluctuations in the thinning programme have occurred between 400 acres and 1,000 acres since the war but a fixed programme is

now operational at approximately 500 acres per annum.

A small produce depot was already in operation near Brandon Station

at the end of the war and this has been extended to operate as a central

conversion depot for Thetford Chase. The present production of the forest

is approximately as follows

(i) Pitwood 19,000 tons per annum

(ii) Pulpwood 20,000 " " "

(iii) Stakes, etc. 7,000 n " "

The volume of saw timber is very small at present but the total volume

of produce from the forest is approximately l£ million cu. ft. per annum.

As the thinnings increase in size every effort is being made to reduce

the costs of extraction and loading on lorries. Experiments are at present being made with the use of wheeled trollies in the woods and mechanical

loading of poles.

A creosoting plant using the open tank system is in operation near

Santon Downham. The annual production is in the region of 70,000.stakes,

2.000 struts, 3,000 gate and other posts, and 3,000 fence rails together

38 with various gates and other odd items. Considerable sales of the creosoted material surplus to our own requirements have been made during 1949-50.

At Swaffham a similar depot has been established since the war on a

proportionately reduced scale.

At the King's Forest thinning, apart from the work carried out in the

very small area of acquired woodlands, has not yet commenced.

As a result of practical experience and the work of the Research Branch

it has been found that a normal thinning cycle of five years for Scots pine

and four years for Corsican is proving the most satisfactory both for

silviculture and administrative reasons.

The following table sets out the thinning programmes carried out since

the war:

TABLE IV Total areas Thinned, Thetford, Swaffham and Kings

P. Year Thetford Kings Swaffham Total

46 839 - 491 1330

47 2547.32 83 466.25 3096.57

48 4216.75 118 1003.6 5338.35

49 5842.25 79.5 503.5 6425.25

50 6067.8 85.6 347 6500.4

Totals 19513.12 366.1 2811.35 22690.57

Nurseries

The original Forestry Commission nurseries in Thetford Chase were

formed on agricultural type soils at bynford and Downham. The former was

the larger of the two and between them these nurseries supplied most of the

original plant requirements of the area. After a short while it was found

necessary to open an additional nursery at Methwold. Fallowing and manuring

of the nurseries were not adopted as a general measure in the early years

but it was soon appreciated that a fertilizer was required and farmyard

manure was normally employed for this purpose. Fallowing was also introduced,

partly at least to aid in the control of cockchafers.

As later acquisitions took place the larger part of the Lynford nursery

was closed down because of poor soil conditions and continued cockchafer

attack and planted up, leaving only that part near nest Tofts. Nurseries

39 were opened in the early thirties at West Harling and Hockham on agricul­ tural sites and in 1948 it was found necessary to close the remaining part of Lynford nursery owing to the impoverishment that had taken place. For similar reasons it has been found necessary to fallow, clean and green crop Downham nursery in 1949-50.

A heathland type of nursery was established at Roudhajn in 1948 and has so far produced excellent coniferous seedlings. Recent practice has concentrated on intensifying the productivity of the nurseries by an appropriate rotation by fallowing and green cropping and the application of composts and fertilisers. Composting depots are operating on a fairly large scale at Santon Downham and West Harling. Hopwaste and straw are the main composting materials together with small quantities of chicken manure.

RESEARCH - Note by the Research Branch

Introduction

The climate of the Thetford district is more extreme in its character than that of the rest of the British Isles.

Low rainfall with frequent prolonged spring and summer droughts, severe spring frosts and an unusually wide range of temperature combine to make the establishment of forest crops peculiarly difficult.

Over much of the area the underlying chalk is covered by blown sand of veiy variable thickness (anything from 4 in. to 10 ft.) which dries out easily and, if bare of vegetation, is often partially carried away by the wind.

The vegetation is largely of a "grass-heath" type composed principally of Festuca and Agrostis species with, or without bracken.

In many places, however, there is a dense intractable layer of almost pure Carex arenaria; this type competes heavily for the small amount of available soil water and is particularly difficult to plant.

It may be seen from this brief introduction that the establishment problems in this forest are largely climatic but are rendered more difficult by both soil type and surface vegetation.

Roe deer are very troublesome over the whole area and deer fencing is necessary for any critical hardwood experiments.

40 Scope of the Experiments

Experimental work commenced in 1927 since when some 32 experiments have been laid down. These are shown in the following table grouped according to date and subject:-

Planting Years

Subject Group 1927 1928 1930 '1931 1932 1933 1934 1935 1936 1943 |l944j 1951 i ------k------

i i { 1. Methods of | 8 j 13 27 planting and \ ground pre­ j 1 15 i i paration. I f i ; : 2. Age, type and ! 8 13! 22 26;

size of plants 1 5 [ i

i 3. Species trials 1 : 3 i

4. Provenance 2 7 | 18 6 I

21 28 5. Nurse crops ! 9 121 17 23 interplanting 1 and under- | 10 14 planting f 1 1 1 1 i 6. Poplars 1 19 29 i ! 3 I 20 A 30 i ! 1 i f I 31 \ I\ 32 | ! 1 I t 7. Nursery ! \ ; J Extensions ’ 4 111 24| ! 1 1 ' I 5 I 1 l I ! : i ‘ I | 8. Miscellane- 1 | j j i i * ous. ! ; 1 1 ! i

In addition to actual experiments a number of special investigations

have been carried out by the Research Branch at Thetford, including:-

(a) The collection of temperature data in connection with spring frosts.

(b) Recording of frost damage to beech and Douglas fir.

(c) Investigation into the results of late beating up.

(d) The collection of data on the growth of Douglas fir in East Anglia.

(e) Studies of Line thinnings of pine plantations.

(f) Collection of data on the yields from first thinnings of Scots and Corsican pines in East Anglia.

Lastly it should be mentioned that there has been a large volume of

sample plot work carried out by the Mensuration Section.

41 1. Methods of planting and ground preparation

Early experiments dealing with types of ploughing yielded clear

information.

Shallow single furrows with the trees planted along the furrow

bottom gave the best results with all species.

Planting on the top of a ridge formed by three upturned furrows

resulted in very heavy failures - probably due to drying out in the

summer.

Pull ploughing - much the most expensive method - gave no advantage

over single furrow ploughing.

After two seasons work the shallow single furrow with plants spade

notched into the furrow bottom was accepted as the standard planting i method and very little further experimentation along this line was

considered necessary.

One or two trials of pit planting showed that any extensive

disturbance of the soil apparently greatly increased the likelihood

of damage due to drought, and results were often worse, and never any

better, than with normal notch planting.

Screefing and notching, while quite suitable for the poor heath-

land with its sparse vegetation, was not so good in areas carrying a

heavy grass mat because the screefing tended to form little frost

pockets below the general grass level. In such thick swards single

furrow ploughing gave the best results.

An interesting practical point peculiar to the district may be

mentioned here. It was found important never to plant very deeply

when notching the trees along the furrow bottoms, because blown sand

carried by the wind during the frequent dry spells always added an

inch or two to the original planting depth before the end of the

summer, and pines frequently die-off if buried too deeply.

On the other hand, if planting on an exposed ridge or shoulder,

it was advisable to plant rather deeper than usual to allow for wind

erosion.

2. Age, type and size of plants

It is always necessary to proceed with the greatest caution when

commenting on the results of experiments under this general heading.

42 Not only are they usually complicated by the questions of different seed origin of plants, but seasonal weather differences may completely reverse the results.

At Thetford with its climate of unusual extremes and its very light soil any generalisations from inadequate data would be particu­ larly dangerous.

There are, however, several points that are worthy of mention.

It is not worth while trying to establish crops by the use of conifer seedlings, the risks are too great and the chances of heavy losses too high.

With beech good results have occasionally been obtained using sturdy seedlings, (usually 2 + 0's) but transplants Beem definitely more resistant to frost and drought in the first season and are a safer proposition.

Direct sowings of beech were a failure.

Several trials have been made comparing the use of large, medium, and small plants of the more exacting species such as beech, Douglas fir and larches.

In general the results show that the medium sized plants are the most successful but one or two points should be explained.

(i) The term "medium" is used to describe a plant between 16

and 24 in. high. Heavy losses due to drought attended the

use of plants over 2 ft. high.

(ii) For large scale work it is essential that the plants are

not too large for normal spade notching but at the same time

have a really good root system. This combination of

qualifications means a medium sized plant.

(iii) When using medium sized plants it is vital that they are

especially well firmed or they tend to become loose in the

soil and will then dry out.

(iv) Really large plants (3 ft. - 5 ft.) have been successfully

used on some local estates but they have been planted in

specially prepared holes at a very high cost.

43 With pines results are perfectly satisfactory using the usual

1 + 1 or 2 + 1 plants and there is no point in going on to larger and

more expensive stock. The use of 1 + 0 pine seedlings resulted in

very heavy losses particularly with Corsican pine. In a large scale

experiment in 1935 (No.26 Hockwold), losses were Scots pine 28$ ,

Corsican pine 90$.

3* Species Trials

About thirty species have been tried in the various Thetford

experiments and their behaviour under different silvicultural

conditions and on the deep and shallow soil types is indicated in the

following table

(XX = very successful. X = moderately successful. F = failed).

Shallow sand over Deep sand over chalk chalk (A - 15 in.) (24 - 48 in.) Species Remarks Pure Nursed Pure Nursed Crop Crop Crop Crop

Scots pine X XX -

Corsican pine XX - XX -

Pinus contorta X - XX -

Pinus jeffreyii -- F -

Pinus muricata - - F -

Pinus ponderosa X XX — A promising spec­ ies though slow to start.

Pinus radiata - - F -

Pinus strobus X Irregular due to blister rust disease. Sitka spruce F F

Tsuga heteropbylla -- - X Only young, may do well yet.

Sequoia gigantea - - - X do

European larch F F X X Usually best in mixture.

Japanese larch F - X - Very uneven crop

Douglas fir FX XX XX Should be nursed (Green) on poorer sites.

Douglas fir F • X — Much poorer than (Fraser river) the green type.

44 Shallow sand over Deep sane I over chalk* chalk ( j h - 15 in.) (24 - 4 8 in. ) Species Pure Nursed Pure Nursed Remarks Cron Cron Cron Cron

Lawson* s cypress F - F -

Cupressus macrocarpa F - F -

Thuya plicata - - F -

Abies grandis F - FX Only young, may do well yet. Abies nobilis F - F X do

Abies pectinata F - F X do

Beech F X F X Difficult to establish but grows well.

Birch F - X - do

Sycamore F - F X Very uncertain results

Grey Alder F - X - do

Sessile Oak F X FX Best nursery technique not yet established.

Pedunculate Oak F X F X do

Red Oak F X F X do

«= General Remarks on Species

The nines

Corsican pine has given the best results and, though starting slower than Scots pine, after 20 years is slightly taller and gives decidedly heavier yields than our native pine.

Comparative figures from Olley's species plots are as follows

Corsican pine aged 23 years - Mean Height of 100 tallest trees per acre = 38 ft. Mean Quarter Girth = 18 in.

Scots pine aged 23 years - Mean Height of 100 tallest trees per acre = M ft. Mean Quarter Girth = 14£ in.

There are three important factors in favour of Corsican as compared

a with Scots pine

i. It is less affected by attacks of Evetria

ii. It suffers less from die-back on shallow soils over chalk.

iii. It is less susceptible to damage by Fomes annosus than is Scots pine.

45 (Percentage diseased or dead in the survey made in ( (1946 - 1947, . 39% for Corsican pine) ) ( 1. kl% for Scots pine )

Against this it should be stated that Scots pine suppresses the surface

vegetation several years earlier than does Corsican and Scots timber is

lilcely to be of higher value.

Pinus contorts grows well and is intermediate between Scots and Corsican

in both height and girth. The form planted at Lynford is the inland one,

the origin being Mt. Ida B.C., where the rainfall is about 25 in. The Olley'a) plot has almost certainly the same origin.

It was unfortunately very severely attacked by Evetria in its early years and there are many crooked stems.

Pinus ponderosa after a decidfedly slow start has become very vigorous

and appears to be a species worth further trial in this and other dry

localities.

At 23 years it has a top height of 33 ft. and mean quarter girth at

15i- in.

Douglas fir

It is evident from the experiment that there is no advantage in using

the Fraser river type of this species as it is far slower and more uncertain

than the normal green (or coastal) variety. Thetford is one of the few

localities where one might have expected the reverse.

On the deeper sands green Douglas has done remarkably well and at

Olley's species plots at 23 years it has a top height (mean height of the

100 tallest trees) of 49 ft. and mean quarter girth of 19s- in.

During the extensive investigations into the growth of this species in

East Anglia, carried out by the Research Branch in 1934 - 35, several points

of interest were noticed:-

1. On shallower soils and in severe frost zones it responds extremely

well to an intimate mixture with Scots pine - over most of Thetford Chase

this should be the best method of establishing Douglas fir.

2. Douglas fir roots will not grow down into pure chalk and therefore

on the shallow drift soils in East Anglia only a limited size of tree can

be expected.

46 On the other hand very deep drift is not essential and 20 in. of sandy soil over chalk will produce small saw timber at least.

3. The species has a very wide range of dates of flushing and at

Thetford the late flushing plants were at a great advantage as regards freedom from frost damage. It was observed, however, that extreme vigour is of great importance in this respect and a really strong early flushing tree often recovers so well from frost damage that it keeps well ahead of a late flushing neighbour of less vigour.

Lurches

On the whole larch is not happy at Thetford and should not be planted on a large scale as the combined effects of frost, drought and shallow soils over chalk make its success unlikely over much of the area.

It should not, however, be dismissed altogether, as on sites out of the worst frost zones and with rather better quality and depth of soil, good stands may be grown. On some of the intermediate ground larch responds well to a Scots pine nurse - this point being demonstrated in Experiment 14 at Croxton.

Generally European larch succeeds better than the Japanese species but in Experiment 8 at Mouse Hall the reverse was the case.

Data for the two species at Olley's, an area fairly typical of the rather deeper drift sand type, is as follows after 23 yeans growth

European larch Mean Height of 100 tallest trees per acre = 35*5 ft.

Mean Girth 16 in.

Japanese larch Mean Height of 100 tallest trees per acre = 34.6 ft.

Mean Girth 16 in.

Beech

Prom the climatic point of view there can be few places in the British

Isles more unfavourable to the early establishment of beech than Thetford.

As a pure crop it is held in check for very many years by the combina­ tion of repeated frost damage and severe simmer droughts.

At Olley1s and Lynford species plots it averages less than 3 ft. high over 20 years; though it should be noted that in these places deer browsing further hindered growth.

47 Unfortunately nearly all the experiments are stocked with plants of mixed origin owing to the repeated beating up, but it is obvious, especially

in the Broomhouse plots, that there is a big variation in the different lots

and the question of provenance is undoubtedly important.

A series of observations on the date of flushing of beech plants brought out the following points

(a) There is a marked tendency for early flushers to be the most

vigorous plants and, despite more damage by late frosts, they

recover well and keep ahead of the late flushers.

(b) At Thetford really late frosts (after the middle of May) are so

common that even the latest flushing trees are often caught.

(c) To be useful any selection of special plants must combine vigour

with late flushing or no great advance will have been made.

The results of several, beech nursing experiments are dealt with.under

section (5) of this report.

Birch

Birch has given decidedly poor results and it is difficult to see why

it has done so badly. It appears very hard to establish when planted yet

grows vigorously as natural regeneration.

Possibly it could be successfully established by direct sowings » immediately after single furrow ploughing.

The only reasonably good result from planting was in Experiment 9 at

Mouse Hall where after 20 years there was a good stocking of average height

27 ft. and mean girth 11.3 in.

Grey Alder

This species gave very disappointing results too. It usually had heavy

failures during the first few years and was very slow for many years. Over

most of the district it is not worth planting.

As with birch, however, there is one good plot on the fairly deep sand

at Mouse Hall in Experiment 9 with am average height of 35 ft. and average

girth of 16.7 inches after 20 yeaLTs.

Oaks

In our experiments oak has been only slightly better than beech as a

pure crop and must be regarded as a failure.

48 It is interesting to note that natural oak seedlings are scattered all over the district in the pine compartments and in many cases are growing up through the pine with remarkable vigour.

There is therefore reason to hope that over much of the area oak may be an easier hardwood to establish than beech.

There seems little to choose between sessile and pedunculate oak in the early years but in the amenity belts red oak appears to be rather stronger.

Notes on results of experiments with Scots pine nurses are given under section (5 ) of this report.

Poplars

These are dealt with under section (6) of this Research note.

Other species

There are many species such as Tsuga heterophylla, Sequoia gigantea,

Abies species, Lawson's cypress, Thuya plicata, sycamore etc., which although failing in the old experiments when planted pure give much better promise in recent interplanting or underplanting.

It will, however, be a few years before definite information is avail­ able.

4. Provenance

The main provenance experiments at Thetford concern Scots pine and

at Croxton twenty different origins are compared including representatives

from the Balkans, Italy, Scandinavia, Prance, Central and Eastern Europe

and five native sources.

Of all the strains tried that from the shelter belts and hedgerows,

which are a feature of this neighbourhood, is outstanding. (Mean Height

of 100 tallest trees per acre at 18 years = 28.0 ft.)

The 'East Anglian' Scots pine, as it is often called, appears to

combine considerable vigour with desirable stem form. It is of interest

that it frequently appears amongst the best strains in trials under / widely different conditions.

The pine from the Foret de Hagenau (Bas Rhin) is as vigorous as the

above but is of poorer form and coarse habit. Pines from lower latitudes

appear uncertain in establishment and tend to develop a coarse branching

habit. 49 The Scottish origins are generally of good form with moderate

weight of branch but they are all slower growing than the local strain,

they average approximately 25 ft. in top height after 18 years. It is

interesting to note that those from Eastern Scotland (Cawdor and

Darnaway) are faster growing than those from farther West (Glengarry

and Glenmoriston).

The Scandinavian pines from high latitudes are far behind the

others in height growth, averaging only 21 ft. in top height after 18

years. In form, however, they are good with well shaped stems and

light open crowns with short branches.

The only other species concerned in provenance trials under this

head is Pinus ponderosa.

In Experiment 7 we have six British Columbian lots, as follows

Mean Height after 20 year3

1. Tappen Altitude 1300 ft. 17.9 ft.

2. Seton Lake " 800 ft. 17.0 ft.

3. Enderby " 1200 ft. I5 .4 ft.

4. Salmon river " 2200 ft. 16.2 ft.

5. Lytton " 700 ft. 16.25 ft.

6. Lillooet " 800 ft. 15.8 ft.

There is not much to choose between these in either form or

vigour, but it may be noted that the Salmon River lot showed consider­

ably the best survival.

It is interesting to note that the very good Pinus ponderosa in

Lynford species plots is of Seton Lake origin and has done much better

than those from the same place in this experiment, but it is on a

deeper soil and on a site rather less liable to frost damage.

Unfortunately the Pinus ponderosa at 011ey*s plots is of mixed

origin.

5. Nurse Crops - Interplanting and Underplanting

A great deal of experimentation has been carried out at Thetford on

the nursing of beech with special reference to its introduction into young

Scots pine crops varying from 4 ft. to 12 ft. in height.

50 It has become increasingly obvious that this intermediate stage of the

pine nurse crop is very difficult to deal with and, whatever the method of

interplanting adopted, much sacrifice of pines has been necessary to allow

the beech to get into the canopy.

Contemporary planting of the pioneer together with more exacting

species may be the answer to this difficulty, but this method is attended with grave risk of high losses in the beech before the pines have any beneficial effect. Nevertheless surviving contemporarily planted beech

will have developed a good root system by the time the nurse crop is beginn­

ing to close canopy, and are likely to put on good annual shoots immediately

the severity of frosts and sward competition is reduced.

At Broomhouse in Experiment 23, planted in 1934- a full Scots pine crop,

averaging approximately 16 ft. high was brashed and underplanted with good

beech transplants. The canopy was not very heavy, the ground vegetation

was killed out and there was practically no danger from frosts. The result

was unexpectedly bad - 85$ of the plants dying by the end of the second

season. It appears that with a complete crop of pine at that age there

is insufficient soil moisture available.

On the other hand if every other row of pine is cut out, when about

6ft. - 8 ft. high, and beech introduced in the open lanes so formed, as was

done in several of the experiments, the combination of the spring radiation

frosts, hot sun and drought holds them back far so long that the pine canopy

closes over them and heavy felling of the nurse species is essential before

it has reached a profitable size.

Prom the results of all this work it therefore appears that unless most of the,pines are to be sacrificed at an early age the beech must be

introduced either simultaneously with the planting of the nurse crop or at

any rate before the pines reach an average height of over three to four feet.

Alternatively it may be possible to bring in the beech in the early pole stage when thinnings are started, probably in groups or strips such as have been created by war damage at Priston, Laughton and elsewhere and in which beech have grown very well.

Birch and alder have not been successful nurses at Thetford being them­ selves too uncertain for a good pioneer crop but introductions of Abies.

51 Thuya. Tsuga etc., are now being made in some of the better plots of both

of these nurses.

Turning to oak, sycamore etc., a great deal of interplanting with

Scots pine was carried out in checked plots of these species in the seasons

1933-34-, but lack of labour during the war period entirely spoilt what

would have been very valuable work.

The pines entirely overgrew all the hardwoods and it is doubtful how

many of the long checked plants will now respond and grow into the upper

canopy.

Prom the reports of 1938 and 1939 it was obvious that with suitable

cutting back of the pines most of the hardwoods could have been brought on

and satisfactory stands might have been obtained.

It was observed that oak got away with pine much more easily than beech

whilst the pines were still too small to offer much shelter, and further

experiments are now in progress along these lines by the introduction of

oak and beech into very young pine plantations.

6. Poplars

There are a number of sites in Thetford capable of carrying poplars.

These are usually drainable water meadows, but surprisingly good growth has

been obtained on much drier sites, provided the depth of free rooting soil

was adequate.

The comparative failure of so many of the older poplar plantings, which

were mainly along the river valley areas, was due largely to unfortunate

choice of varieties most of which were subject to canker damage. In other

canes the trouble was waterlogged ground.

General H. G. J. de Lotbiniere planted an interesting plot of poplars on

Ling Heath on a relatively high and dry site from 1925 - 1930*

Many became badly cankered but one variety Populus eugenei. (ex

Col. Pratt's collection) is remarkably healthy and vigorous even though

surrounded by cankered trees, including other Populus eugenei of an inferior

clone.

Experiments on problems of establishment such as age and type of

plant, planting methods and the use of manures are now in progress using

canker free varieties such as Populus serotina. and its narrow crowned

52 variety, robusta, and gelrica.

7. Nursery Extensions. .

The extension to the forest of certain nursery experimental treatments

(on Scots pine) showed, (as so often noted elsewhere), that; (a) spacing in

the transplant lines has little effect on survival in the forest and that

(b) grading of seedlings prior to lining out does not produce transplants

of observably different performance.

Grading of transplants prior to planting was usually included as a

treatment in these experiments. The poorer grades ("culls") suffered

markedly higher losses.

8. Miscellaneous

Under this heading comes a number of reports and special investigations

which are briefly dealt with below:-

(a) Sample Plots

A great deal of mensuration work has been done on both Scots and

Corsican pine at Thetford and the following is a summary of Mr.P. C. Hummel's

article, "Thinning Study in Young Pine" which appeared in Forestry (Vol.

XXIII Number 2, 1950).

"Summary

1. Thirteen Scots pine (Pinus sylvestris L.) and fourteen Corsican

pine (Pinus nigra var. calabrica Schneid.) plots were established

in East Anglia between 1938 and 1943 in 18 - 25 year old plantations,

in order to determine the effect of different thinning treatments

on increment, thinning yields, and general development of the stand.

2. Periodic annual increment has averaged 150 cu. ft. - 200 cu. ft.,

quarter girth, over-bark, per acre, per annum, in Corsican pine;

and 100 cu.ft. - 120 cu. ft. in Scots pine. The under-bark figures

are about 17 per cent. less.

3. Thinnings between the ranges of B and D grades do not seem to

affect volume increment appreciably, but thinnings heavier than a D

grade cause a definite loss in increment.

4. Very heavy thinnings (D + + ) have caused a loss in increment per

acre but have not produced a check in the rate of growth of the

53 surviving trees.

5. There is some evidence that heavy thinnings increase liability

to attacks from Fomes annosus Fr.

6. The present moderate thinning policy in East Anglia appears

to produce average thinning yields of about 30 cu. ft. to 40 cu.ft.

quarter girth, overbark, per acre, per annum, for Scots pine,

and about 50 cu. ft. for Corsican pine, starting at an age of about

12 years."

In addition to this Mr. W. M. Flentje and Mr. P. G. Gough published an article on "Line Thinning" in the Empire Forestry Review (Vol. 25 No. 2

1946), and Mr. Gough also carried out a large series of 1/lOth acre plots for determining the yield from first thinnings of Scots and Corsican pines.

(b) Between 1933 and 1935 extensive meteorological observations were made in connection with spring frosts, and phenological studies were made on such species as beech and Douglas fir.

Much of this work was incorporated in the Forestry Commission

Bulletin No.18 "Spring Frosts".

(c) Observations were made on the growth and survival of plants used in the beating up of pine plantations. These showed that the practice of beating up small blanks later than the first year after planting was wasteful of plants and it was discontinued.

(d) A survey was made of the growth of Douglas fir in the Thetford district. This was not published as it was felt that so many of the plantations reported on were rather young at the time and that a later report should be incorporated.

It did, however, bring out several points which are mentioned earlier in this report under section (3) - (Species trials).

(e) A research team carried out a survey of Fomes annosus damage in

East Anglian pine plantations; and later the work was extended to other tree species by Mr. J. Risbeth whose valuable studies were published in five parts, three appearing in "Annals of Botany" (Vol. XIV No.55 and

No. 57 and Vol. XV No. 58) and two in "Forestry" (Vol. XXII p. 174 - 183

54 and Vol. XXIV p.114 - 120),

(f) During the early years of the pine plantations the severe attacks of Evetria buoliana necessitated the close study of this problem by the entomologists.

Much of this work was published in Forestry Commission Bulletin No.16,

"Studies on the Pine Shoot Moth", by Messrs. G. C. Brooks and J.M. B. Brown.

Mr.Brown also studied chafers in the East Anglian nurseries.

It is very clear that the establishment problems in Thetford forest are largely climatic but are rendered more difficult by both the soil types sind in places by the surface vegetation.

(i) Methods of planting and ground preparation

Over most of the area the best planting method is by shallow single furrow ploughing with notch planting in the bottom of the furrows.

If screefing is done instead of ploughing care must be taken not to make a deep depression or a "micro" frost pocket is created.

Owing to drifting sand deep planting must be avoided.

(ii) Age, type and size of plants

For beech medium sized (16 - 24 inch) trsinsplants gave the best results but sturdy seedlings have been used with success on several occasions.

Pines and most other species have taken best as 1 + l*s or 2 + 1*s.

Conifer seedlings have usually given bad results.

(iii) Species trials

Corsican pine appears to be the most reliable and vigorous species but Scots pine is good once past the Evetria damage stage.

Pinus ponderosa and Pinus contorta (inland form) are both good but the former is preferable as it is less affected by Evetria and its timber is of better quality.

Douglas fir, except on the shallowest soils, has grown better than might have been expected, especially with pine nurses.

European larch should not be planted on a large scale but may be planted on the deeper soils out of the worst frost zones.

55 With pine nurses, both beech and oak will probably ultimately succeed over a large area of the forest.

On selected sites canker free varieties of poplar may be well worth while - see section (6).

(iv) Provenance

Scots pine from local sources has given the best results but that from

Eastern Scotland is also quite good.

Of six lots of Pinus ponderosa those from Salmon river B. C. appear easiest to establish, there being little to choose in other respects.

(v) Nurse Crops - interplanting and underplanting

The ideal way of introducing beech into the pine plantations at

Thetford has not yet been found but the following brief statement may help.

(a) If beech are introduced into the pine crop when the latter

is between 4 ft. and 25 ft. high then a very large number

of the pines will have to be sacrificed in order to get the

beech away.

(b) Simultaneous planting of the two species in intimate mixture

is probably a better method but there is a risk of high losses

in the beech before the pine are large enough to afford any

protection. The same applies to early introduction before

the pines are 4 ft. high.

(c) Some beech introductions to pole stage pine crops have done

well, these have been planted in small groups or strips below

openings in the canopy. Birch and alder have failed as early

nurses but they may prove useful on sheltered sites for

underplanting at a late stage.

(vi) Poplars

The varieties at present recommended as being canker free are - serotina, serotina n.c.v. robusta. gelrica and the canker free clone of eugenei.

Previous failures have been largely due to the unfortunate selection of varieties and to planting on bad sites.

M. NIMMO, - Asst. Silviculturist (s) 56 4th March 1952. Conclusions

Despite the vicissitudes and doubts of the early days it can be said that the large scale afforestation of the Brecklands areas comprised in the three forests of Thetford Chase, Swaffham and King's, has been a success and the area is now in such a stage of production that it is regarded as a show place for the large scale work of the Forestry Commission and is a testing ground for policies and operations for application, with modifica­ tions, to" the other more extensive afforestation schemes which are being built up in the north of England and in Scotland.

It must be remembered at all times that these Breckland forests are not strictly comparable to any other areas administered by the Forestry

Commission in view of the flat nature of the country and the dry conditions under foot allowing for the passage of traffic and transport to all parts of the forest provided it is not obstructed by tree growth.

Many problems yet remain unsolved in respect of these areas from the silvicultural point of view as we have reached a stage where very serious consideration must be given not to the remaining forty to seventy years of the present rotation but what shall be regarded as a suitable following crop for the second rotation. These considerations do not always apply in other smaller units where once a satisfactory crop has been achieved on the ground one has a wider choice of species for use in succeeding rota­ tions.

There are also many problems to be ironed out in respect of the administrative aspect of this large scale afforestation, in many cases these are due to the inadequate numbers of the technical staff available and many difficulties would not exist today if more experienced District

Officers and Foresters were to hand to run the area.

Many of the awkward aspects of organisation and maintenance of a steac^ sequence of operations can be overcome, and a co-ordinated flow of produc­ tion achieved, by the presence of a Senior Officer stationed in the Forest area and responsible for all activities.

Analysing the conclusions from a technical point of view the following observations can be made:

57 (i) Sites and Species

It has been found that the most successful conifer species for large scale work on these areas is the Corsican pine and, despite its slow initial rate of growth, it has produced the largest trees with the greatest volume in a much shorter time than the Scots pine. Corsican pine has been found to be far less frost tender than was originally anticipated and can non be used with confidence over all but the worst low lying sites.

Scots pine should be confined to low lying wet areas or as a nurse to other species, mainly hardwoods, if these are necessary.

The rate of growth of Scots pine, although satisfactory from a purely afforestation aspect of getting something on the ground that will grow, is disappointing as regards potential volume production and it is anticipated that the rotation for this species may have to be as much as 120 years before reasonable size millable timber is available.

Douglas fir has not been used extensively but it shows reasonably satisfactory results, both in height growth and volume production, when mixed with other species on the slightly better sites, i.e. avoiding the pure deep sand areas. Probably its best use is that of a beat-up plant where this operation is delayed or where plantations have received damage of one sort or another.

Other conifer species are not, on the whole, a success as the rainfall is insufficient, although on very limited areas which can be specially selected a variety of conifer species can be made to succeed subject to very detailed technical supervision.

Oak now shows evidence of promising growth on many sites, other than bare sand areas, and many of the plantings carried out in the early 1930's of oak/pine mixtures have now had the pine removed leaving successful stands of the hardwood. It is probable that once initial forest soil conditions have been established by a first crop of conifers, the use of oak could be extended to poorer sites still but it is doubtful whether the large scale use of oak is justifiable where volume production of Corsican pine is so much more rapid. It is doubtful, also, if volume production of oak will ever achieve that of the richer heavier soils in other parts of the Kingdom.

Beech is showing very considerable promise, particularly in mixture

58 or partial mixture with pines and it appears to thrive as an underplanting or second crop on all sites where the chalk is relatively near the surface.

Nov/ that the deer and rahbit populations have been reduced to a level where they are properly controlled, evidence is appearing everywhere of the relatively rapid early growth of beech and it is anticipated that over much of the Chase this species could be used far more extensively in the second rotation.

Red oak has, of recent years, been used in plantation form and not merely as occasional ornamentals on road side belts. Despite its poor quality timber it grows fairly rapidly on the poorer sites and is undoubtedly a tree of the future for these Breckland areas.

On the low lying riverside bogs and fens poplar can be used provided it is of canker free strain. Many of the earlier poplar plantations have failed as a result of canker and this disheartened those in charge for many years but now that canker resisting strains are available the position should clear. In addition to these old woodlands and fen or bog areas, there are extensive stretches of Norfolk reed and Phra finite s where poplar afforestation has yet to be tried; if this does not succeed the only alternative is alder.

Mixtures. Few instances exist of true mixtures where these were originally intended as such. In the main mixtures have been planted with a view to using the conifer as a nurse for hardwoods and, in most cases, the conifers have been, or will be, cut out in about the 20th year after planting. However, it is hoped that in many cases a few conifers can be kept in these hardwood crops up to a limit of, say, 20 6r 30 per acre.

Occasional mixtures of Scots pine and Douglas are met with and, if the latter species is to be kept standing in the soft ground and against the strong winds, it is probable that these mixtures will have to be retained for the full rotation, This will, however, entail the freeing of a number of the better Scots to allow them to get through and compete with the faster growing Douglas.

(ii) Preparation and Planting

Very little of the area at present acquired remains to be planted but it is possible that in the course of time further expansions may take place.

The planting technique now in use appears to be fully successful and no

59 drastic revision is deemed necessary.

Ploughing and, in places, sub-soiling with a double-shared screefing plough provides all the necessary cultivation desired and reduces initial

■weed growth around the young trees, planting should be in the bottom of the furrow to obtain the greatest amount of moisture. Drainage is seldom necessary on the more sandy soils but it is required in the low lying riverside poplar areas.

The main problem in all new planting work is the extermination of rabbits as these abound in countless thousands on all open ground and fencing is sin absolute essential prerequisite of any afforestation coupled with intensive warrening and regular maintenance of this aspect of opera­ tions.

(iii) Plantation Maintenance

Although beating up on a very extensive scale has been necessary in the past, mainly due to poor quality plants used and a lack of appreciation of the full troubles that follow insufficient warrening, it is found that with better stocks now to hand, this operation - except in very rare instances - is a minor one.

Weeding has to be carried out for three and, in certain cases, four years after planting but normally it is light work and is only of serious consequence where patches of gorse, bracken or snowberry are encountered.

Owing to the generally poor nature of the ground afforested, cleaning as an operation for the removal of coppice and shrub growth interfering with the crown development of established plantations is very seldom met with in the Breckland area and what patohes are encountered are normally dealt with at the time of brashing. This latter operation is, of necessity, a standard feature of maintenance work and has to be carried out to allow access for marking thinnings and also to ease the fire danger.

(iv) Thinning

Since the last war thinning operations have been organized on the basis of a five-year thinning cycle for Scots pine and a four-year thinning cycle for Corsican pine, and these have proved satisfactory and should serve until, probably, the fourth or fifth thinning. The normal practice is for thinning to consnence for Corsican pine about the 17th year and for

Scots about the 20th year but owing to the irregular rate of planting and

60 the necessity to maintain a steady flow of thinnings, adjustments are necessary and are reviewed according to the rate of growth in each planta­ tion prior to it coming into a thinning cycle.

(v) Fellings and Replantings

Little felling has, as yet, "been undertaken and almost none in plantations formed by the Forestry Commission. A number of old acquired woodlands have been cleared and more will fall into this category in the next few years as they are all more or less in a state of maturity.

When replanting old woodlands ploughing is not possible and hand screefing has to be resorted to. In the main, the recent replanting of these old woodland areas has been carried out with hardwoods to provide a mixture of leaf mould goad a variety of aspect over the forest area together with improvement to fire breaks. Where replanting on a larger scale is undertaken and conifers are used, a resting period of some three years must be observed between the felling and replanting to avoid beetle and weevil damage.

Natural regeneration is in evidence in many places but it is doubtful whether this can be regarded as of sufficient stocking at this stage to form a second crop, except over certain small and limited areas.

(vi) Fire

Losses from fire in the past culminating in the major disaster in

1946 have made heavy inroads in the afforestation of the Breckland areas.

Following this, more adequate fire protection measures were adopted involving permanent fire fighting units and these, despite the general development of plantations for these forests, will have to be maintained.

The cost per planted acre, however, is relatively small compared with the area at risk and compared with plantations in other parts of the Kingdom.

61 HISTORY OF THETFORD, KING'S AND SWAFFHAM FORESTS

APPENDIX I

Notes from Inspection Reports

Date Thetford

24-25 April, 1924 Mr. Taylor, Mr. Forbes

14 May, 1924 Lord Lovat

12 April, 1926 Lord Lovat

October, 1926 Assistant Commissioner

24-28 June, 1929 Technical Commissioner Sir R. L. Robinson

9-10 July, 1931 Sir R. L. Robinson

18-19 Sept. 1931 Assistant Commissioner

15 Feb. 1932 Assistant Commissioner

1-3 June, 1932 Assistant Commissioner - Parliamentary Secretary to Ministry of Labour.

22-24 Oct. 1932 Chairman

12-15 May, 1933 Sir Alexander Rodger, Commissioner

9-14 Feb. 1934 The Chairman

5-5 June, 1934 Assistant Commissioner

5-6 July, 1934 Chairman and Advisory Committee

15-17 Aug. 1934 Assistant Commissioner

12-14 Dec. 1934 Chairman

28 Feb.- 1 March 1935 Assistant Commissioner

17 March, 1936 Assistant Commissioner and Sir Alexander Rodger

5-7 May, 1936 Sir R. Robinson

10-11 Sept. 1936 Assistant Commissioner

10-11 Nov. 1936 The Chairman

24 March, 1937 The Chairman

9-11 Aug. 1937 Assistant Commissioner

28 March, 1938 Chairman

14-18 April, 1938 Assistant Commissioner

20-22 Aug. 1938 The Chairman

9 Dec. 1938 W. L. Taylor, Esq.

25-26 Oct. 1939 Sir John Sutherland, Commissioner

23-25 Oct. 1940 Sir John Sutherland

62 Date Thetford

23 Feb. 1941 Chairman

28 Sept. 1941 Chairman

1-2 March, 1942 Chairman

2-4 April, 1942 A/Asst. Commissioner, Mr. A. P. Long

21 July, 1942 Chairman

2-3 Oct. 1942 Chairman

3-6 Nov. 1942 Mr. D. J. K. Quibell - Commissioner

7 March, 1943 Commissioner - Mr. W. L. Taylor

21-22 May, 1943 Chairman

24 June, 1943 W. L. Taylor, Esq., and Representatives of Norfolk, Suffolk and Cambs. Naturalists Trusts.

9 June, 1944 Joint Inspection with L. N.E. R. representatives.

21-22 Aug. 1944 A/Assistant Commissioner

24-26 Nov. 1944 Chairman

5-8 April, 1945 Chairman

12-13 May, 1945 Commissioner - Mr. W. L. Taylor

27 Sept. - 3 Oct. 45 Assistant Conmissioner - Mr. 0. J. Sangar and representatives of Celotex

20-21 Oct. 1945 Chairman

9 July, 1946 Major Charles Mitchell

30 Nov. 1946 Mr. Connell

10-11 May, 1947 Chairman

31 Aug - 3 Sept. 1947 Director General and Chancellor of Exchequer

7 Feb. 1948 Director General and Director (E)

16-18 April, 1949 Chairman

21-22 May, 1949 Chairman

8-11 Nov. 1949 Mr. C. A. Connell, Conservator S. F. England

29 March, 1950 Mr. C. A. Connell, Conservator S. F. England

12 April, 1950 Chairman

31 May, 1950 Director (E)

27 April, 1951 Chairman (N.C.E.) Lord Radnor

63 Date King* s

11 Sept. 1935 Assistant Commissioner

20 Nov. 1935 Chairman

17 March, 1936 Assistant Commissioner

5 May, 1936 Sir R. Robinson

11 Sept. 1936 Assistant Commissioner

6 Nov. 1936 Chairman

9 Aug. 1937 Assistant Commissioner

7 Jan. 1938 Assistant Commissioner

15 April, 1938 Assistant Commissioner

9 Dec. 1938 W. L. Taylor, Esq.

26 Oct. 1939 Sir John Sutherland - Commissioner

24 Feb. 1941 Chairman

29 Sept. 1941 Chairman

22 July, 1942 Chairman

2-4 Oct. 1942 Chairman

4 Nov. 1942 Commissioner D. K. J. Quibell

8 March, 1943 Commissioner W. L. Taylor

25 June, 1943 Commissioner W. L. Taylor

24-26 Nov. 1944 Chairman

5-8 April, 1945 Commissioner W. L. Taylor

2 Oct. 1945 A/Asst. Commissioner

20-21 Oct. 1945 Chairman

31 Aug. 1947 Director General

21 May, 1949 Chairman.

Swaffham

March, 1933 Mr. Sangar

15 May, 1933 Sir Alexander Rodger

6 May, 1936 Chairman

10 Nov. 1936 Chairman

25 March, 1937 Chairman

9 Dec. 1938 Assistant Commissioner - Mr. Sangar

25 Oct. 1939 QomnissiflDQ! - Sir J. Sutherland

22 Feb. 1941 Chairman

21 July, 1942 Chairman

64 Date Swaffham

3 Oct. 1942 Chairman and Sir William Jowitt

7 March, 1943 Commissioner Mr. W. L. Taylor

Commissioner Mr. Philip Price.

22 Aug. 1944 A/Asst. Commissioner

24-26 Nov. 1944 Chairman

5-8 April, 1945 Chairman

21 Oct. 1945 Chairman

11 May, 1947 Chairman

30 Aug. 1947 Director General and Mr. Hugh Dalton, Chancellor of Exchequer.

29 March 1950 Mr. C. A. Connell - Conservator of S. P. England

65 ’ THETFORD FOREST

Sir Roy L. Robinson's Visit - 9th-10th July 1931

Instructions given at a meeting held at Santon Downham

(a) Existing Beech-Conifer Plantations

These 'were separated into three categories with undemoted estimated acreages:

(i) Fully stocked and beech beginning to show some growth - 300 acres

(ii) Beaten up with Scots pine now almost complete coniferous plantations - 250 acres.

(iii) Balance in a more or less unsatisfactory condition - 1200 acres.

(i) is to be rounded off in P. 32 and left.

(ii) is to be left.

(iii) 130 acres of this is to be dealt with in P. 32, taking various

mixtures and ground types and various methods of dealing with it

are to be tried at a minimum of 1000 beech in the crop. Possible

lines are making up with beech in the usual way where there is

some cover, e.g. Compartments 206, 207 and 208 and behind Leper

Lodge,, deep ploughing between conifer rows and planting beech,

group planting of beech, addition of Scots pine, etc.

In addition to above P. 29 is to be beat up with Scots pine thus

adding 100 acres to category (ii).

(b) Future beech plantations

The 80 acres resumed from W. Quadling are to be planted half with beech plus larch and half beech plus Scots pine - with complete ploughing etc. plus rye as already arranged. The 3000 beech + 1000 conifer per acre mixture used at Rendlesham for oak in P.31 is to be used.

Only first class plants are to be used, to be purchased if necessary, and well planted, i.e. cost is not to be first consideration.

A roadside ares on P. 32 Croxton planting is to be similarly treated.

(c) Fire Plans

Progress of Thetford fire plans reviewed. A case for 1 or more fire towers to be put up when plan completed.

(d) Roadside hardwoods belts

i) All existing pure hardwood belts to be planted with 1000 Scots pine per acre as nurses in P. 32. 66 II) The aim in future is to he the establishment of beech belts, 2-5 chains wide - along all roads, where soil conditions are suitable. Scots pine is to be planted in advance at 9 ft. x 4^ ft. and beech brought in in groups of 3 when these nurses have come away.

The use of poplar in such belts is to be discontinued.

Ill) Beech is to be brought into roadside belts at Redneck or Trainee road where pine 3 ft. - 5 ft. high by cutting out alternate rows of pines and grubbing of roots by trainees.

Chairman’s Visit - 5th Kay. 1936. Elveden - Broomhouse Compartments 5 and 6. P. 22.

Inspection re possible treatment of such plantations for removal of wolf trees. Suggested that treatment probably could lie along lines of brashing one row of trees, leaving 2 or 3 rows, brashing one row, and so on, so that sufficient racks would thus be provided for picking out and felling wolf trees. Work would be done with either billhook or handsaw.

Research Branch beech plots seen. Noted that many transplant beech dead from frost and drought under apparently frost proof shelter. These beech were planted P. 34. P. 30 and P. 31 seedling beech also frosted but alive and flushing.

Assistant Commissioner’s Visit - 10th and 11th September, 1936. Brandon Park.

A general circular walk was made over this property. Considerable suitable natural regeneration of Scots pine seen, which is to be thinned out and pruned. Question of future restocking by natural means discussed, and agreed that much will be possible, but that certain large open areas will have to be planted.

Something should be done in the way of scratching the ground required for natural regeneration.

Prevailing type of Scots pine parent tree considered to be good.

There are some rough old misshapen trees which might be carefully removed by trainee labour.

The care of existing and use of further birch advisable. Later use of Abies grandis under the birch might be considered. The main vista from the House should be maintained and the beech on each side of this avenue should be freed from any hampering trees of other species.

67 Chairman and Assistant Conmissioner's Visit - 24th March 1937

The Chairman discussed the incidence of deer on the forest and noted

that it might he necessary to appoint an official deer-catcher so that the

Department would "be independent of relying on the action or help of the

shooting tenant to keep down these beasts.

I think that the possibility of damage by hares has not been given

full weight.

Chairman's Visit - 24th March. 1937

I am slowly coming to the general conclusion that a good deal of the lack of success in roadside belts is due to grazing - whether by deer, hares or rabbits. The large inclosure we are making in the mixed beech/

Corsican pine area will give us some indications on the subject. I think, however, that as in the New Forest we might test the assumption by making a number of small enclosures (netting) in various places.

Chairman's Visit - 28th March. 1938

High Lodge Forest was Inspection/made of the growth of beech inside and outside the deer fence erected a year ago round Compartments 203, 204 and part 207. It was

seen that growth inside the fence was definitely better than outside, and

the Chairman discussed the suitability and costs of enclosing the whole

1150 odd acres of conifer/hardwood forest, together with the alternative

of a greater and constant campaign against deer by an additional number of men constantly engaged on such work. The cost of netting the whole area would be approximately five hundred pounds.

The Chairman instructed that more pruning of the Corsican pine rows

should be done, areas being judiciously chosen, and sufficient area untouched to be left to provide comparative data. He also instructed that

a small schedule should be made outside the deer fence of the ratio of browsed to unbrowsed .beech plants.

Evening Discussion on Hardwood Belts - Chairman. Assistant Commissioner,

Divisional Officer and District Officer - 20th August, 1938.

The Chairman commented on the irregular and, for a large part, poor growth of the hardwood belts. There are approximately 20 miles of main

road and 12 miles of secondary road along one or both sides of which the

68 hardwood belts are scheduled.

The Chairman instructed that an inventory should be prepared having three categories l) Satisfactory, 2) Stocked but not yet satisfactory, and 3) Unsatisfactory, into which all the hardwood belts are to be divided.

Once having this information a determined effort must be made to stock and develop a portion each year. The Chairman further stated that he saw no reason why the hardwood belts should not be considered as eventually usable plantations, and to that end only merchantable trees such as oak and beech, with a sprinkling of flowering trees on the verge, such as wild cherry should be used. Birch has a use only as a nurse and should not be put in as a crop tree. It was pointed out that serious efforts had been made each year for the past three to fill up hardwood belts and that where plant supplies allowed, oak had been used.

The Divisional Officer found himself unable entirely to agree with the

Chairman and Assistant Commissioner that beech is the best tree in this neighbourhood and stated that he considered oak more likely to be satisfac­ tory.

On the question of quicker establishment of these hardwood belts, the damage by deer was discussed at some length. The Assistant Commissioner suggested the use of hounds for tracking and driving down deer, use to be made of them except during the period mid-April to end May. The Divisional

Officer stated that he could foresee serious trpuble with the shooting tenants but he was instructed by the Assistant Commissioner to take no notice of such complaints, but to push ahead with the killing of deer. It was tentatively arranged that a coqple of hounds should be sent up from the

New Forest and also a calling reed. The Chairman raised the matter of guns and said that it would be highly advantageous to have an expert man on each beat armed with a gun, with a roving commission, his competence being judged by the head of deer he brought in. During the unsuitable hours for deer catching he would go on ordinary warrening duties. The Divisional Officer stated that he had always been and still was very loath to issue guns to all and sundry and that it would also be a difficult matter to supervise and control efficiently men with roving commissions. Moreover it is a difficult matter to have a man part-time warrening on other warreners' areas. The

Assistant Comnissioner said that no reasonable request for a gun permit

69 would be refused. The Chairman stated that he wished additional stretches of hardwood belt netted in against hares and deer on the lines of the experimental bits already done.

Chairman's Visit - 28th September 1941

High Lodge Beat - The Deer Pen

Mixtures of Corsican pine and beech, and European larch and beech P. 26.

Nearly the whole of this area is within the danger area of the Thetford

Rifle Range, which has been in constant use since the beginning of the war.

Structural alterations and extensions were made to the range in the sumner of 1941 and advantage was taken of this period for thinning the whole of the Deer Pen. The Chairman was pleased with the results of this work and stated that it had been sufficiently opened to last for another four years.

He asked for information to be supplied to him on the exact quantities of poles removed and produce prepared therefrom. This information will be supplied as soon as conversion of poles is complete, together with financial details of costs and income.

The European larch/beech part does not show the same promise. The beech are fewer and not so forward, while the ground vegetation is dense grass with bracken in parts. As the larch will have to be felled when 30 -

35 years old (becoming pumped after that age) the future management of this area will present difficulties. It may be that Douglas fir planted in groups among the scattered beech will give a solution.

A smaller area of Corsican pine/beech outside the pen was inspected and the Chairman was surprised to see the even stocking of beech here, although with only a few exceptions they had been regularly browsed down to a height of about 18 in. He said that if it were possible it would be both interesting and instructive to include another block within the Deer

Pen, which might gradually be extended over a period of years.

He deduced that the deer were being kept fairly well in check from the fact that there had been a negligible amount of browsing on the current year’s shoots, but he expected that these would suffer in the coming winter.

Chairman's Visit - March 1st. 1942

High Lodge Beats - Compartments 113, Scots pine P. 25.

Owing to the constant drain on the supervisory staff and the most intelligent of the labourers, a time is envisaged when the quantity of

70 thinning to be done on Thetford Chase cannot all be marked by the supervisory staff and it was therefore decided to try and work out a rule of thumb method by which unskilled and semi-skilled labourers could mark their own thinnings.

In Compartment 113 a series of 5 sample plots, each 0.3 acres, was laid down in 1941 and treated on the following lines :-

1. Removal of all deformed stems.

2. Removal of all predominants and dominants of stem form Class 3

3. As 2. where the stem deformation occurred below 14 ft. in height.

4. Removal of all predominants.

5. Selection of 250 good quality trees per acre (saw pruned to

10 ft. to 12 ft. high) and thinning to free their crowns.

Objections were raised to all these treatments on one ground or another, but it was finally decided that a trial should be given to treat­ ment No.1 on an experimental scale and that this should be closely inspected before being tried out further. It was agreed that a certain degree of supervision is still necessary with even the most rule of thumb method, and this will continue to be given by the forester in charge of the unit. The

Chairman was particularly interested in the recovery and subsequent progress of released slender co-dominants of good form and stated that insufficient data was available on this subject. He suggested that, say, 25 of the trees in each of these plots should be numbered and measured with a view to determining which class of tree put on most volume and where, and which of them would be blown down as a result of the comparatively heavy thinning.

In the ensuing discussion it was pointed out that the women measurer appointed on the Chairman’s instruction at Rendlesham had proved to be extremely valuable and it was suggested that an intelligent woman could well be trained in the marking of thinnings. The Chairman was completely in accord with the idea and said that the forest would undoubtedly benefit considerably by a number of superior young women who could be trained to carry out technical field work such as thinning on all those beats where similar conditions apply.

71 Chairman's Visit - 2nd March. 1942

Compartment k3 P. 38

A short walk -was taken into the fifty acre plantation which had been felled in the middle twenties and was replanted with beech and oak in P. 38» full advantage being taken at that time of all the coppice and scrub shelter. The Divisional Officer stated that this area had been one of considerable trouble and after virtually replanting it twice, it was being beaten up this year heavily with Scots pine, in the hope that this nursing species would in due course rear up a reasonable number of the original hardwoods. Management throughout had been carefully done, and for instance weeding had never been neglected, but it was just one more instance of the difficulty always found in East Anglia of re-afforesting old woodland sites. The Chairman and the Divisional Officer once or twice during this tour discussed this phenomenon and agreed that it cuts across all acoepted theories and practice and presents an interesting but curious problem for the Research people. The Divisional Officer stated he was particularly anxious about the matter as our past experiments did not augur at all well for the large amount of replanting of old woodland areas which will be undertaken after the war, consequent on all the Timber Production Department fellings.

Chairmans Visit - 20.3.42.

High Lodge. Compartment 113. P. 25.

The experiment of allowing workmen to do the felling without previous marking will require very careful watching. Similar procedure on a large scale would require constant and close inspection. I am in favour of the alternative proposal, viz. training intelligent girls to do the marking.

Chairman* s Visit - 2nd October. 1942

A general inspection was made of the Broomhouse area, which is one consisting of large blocks of Scots pine and Corsican pine planted between

1922 and 1926. Particular attention was paid to a recent very heavy thinning in Compartment 6, where the stocking bn an acre has been brought down to 350 stems as against the normal figure of 1300/1400. The Chairman explained that he was seeking data as to the possibility of getting a substantial yield of pitwood per acre off such plantations and yet being left with the basis of a crop for future development and retention. It is feared that considerable pressure might be brought to clear fell for

War purposes these areas of pitwood and the aim is to see whether the demand can be met without completely despoiling the plantations.

Chairman's Visit - 21.5.49 22.3*49

The Chairman considered that in view of the lack of information relating to the treatment of beech under nurses it was imperative that research be carried out with the object of obtaining data which could be issued in the form of practical instructions to foresters. He instructed that the

Research Branch be approached to ascertain whether the experiment (10 P.30,

12 P. 31 and 17 P. 32) in Compartment 7 of Wangford Yr'oods had not now filled its original purposes and if so whether these and similar experimental plots could be utilized for further light experiments with the objective of determining the amount of light required by the beech at the various stage and under the particular site conditions. It would also be of advantage to know the duration of response to each increase of light in terms of height growth erect. He stated that in order to be of practical value the acquired information should be distributed in terms of site conditions, species, trees per acre and height, etc. He also emphasised the necessity for placing on record all treatment that had been carried out and all proposed treatment.

The Director General had little to add to the remarks of the Chairman.

He was of opinion that in most cases the retarded growth of beech under nurses was obviously the result of incorrect light conditions and consid­ ered that this indicated the necessity for higher shade. He suggested that where it was proposed to introduce beech under an established nurse the desired stage of the overwood could probably be obtained by maintaining 9 a closer canopy for a further period than usual before introducing the beech.

Cultivation of Beech in Thetford Chase.

There appears to be two problems :-

A. Management of existing beecty^Scots pine and beech/European

larch plantations, and

B. The proper treatment for further areas in which beech is to

form the major crop.

73 With regard to A. the problems arise mainly from the plantations formed by Dr. Steven in which the beech and Scots pine or European larch were planted at the same time.

It is unfortunate that owing to the exigency of the War these planta­ tions did not receive treatment at a critical period. Nor was it realized for a little while after more labour became available how urgent was the work. There were so many urgent silvicultural matters requiring attention at the same time. That position altered in 1947/4-8 and there has been little excuse from the labour point of view since then.

In fairness to those concerned, including nyself, it must be said that during 1946/47 the thought uppermost in our minds was the safety of the forest from fire and the work of ride cutting and improvement of access was given priority over all else. I see no reason to think that we were anything but correct in our assessment of the position and in the action taken.

To return to the plantations concerned, to my mind the main difficulty now is lack of a sufficient number of beech to form a reasonably selected final crop. In some spots where very little beech exists I think there is still time to make this good, but this refers only to a very small percent­ age of the total area. Por the rest we must accept what crop remains and make the best of it by carefully nursing the beech up through the pine crop

It is a matter of nice calculation to give as much light as is necessary without unduly increasing the frost damage. The whole problem is to keep this balance properly adjusted until the beech are well up, say 15-20 ft. in height.

It is a matter on which it is difficult to lay down any hard and fast rules. Conditions change from area to area and from tree to tree and it is essential that an experienced officer should give the operation close and frequent supervision.

One cannot leave this matter without enquiring as to why the beech crop is so thin. Sufficient were planted. I am inclined to think this is due to an attitude of mind of those intimately concerned with the care of the plantations. I suspect that someone followed Dr. Steven who despaired of the beech - many die when planted in the open especially in an

74 unfavourable season as I know from the experience of 1947. As a consequence I surmise the beech were not adequately beaten up and now we are left with an insufficient crop. It is a lesson that, if we are to plant the two species simultaneously, a proper crop of beech must be maintained from the start.

I am afraid that in some cases we can now only hope for a somewhat rough beech crop. A little pruning would certainly help when the selec­ tion is poor but there is no end to this and one could go from short- handled tools to long-handled tools and then to ladders, and in the end have an unsatisfactory crop. Nothing can replace an adequate number of trees on the ground.

With regard to B. there appears to be three main ways of tackling the problems :-

X. Planting beech and nurse together at the same time.

Y. Planting the nurse ahead of the beech and introducing the

beech when the nurse is say 4ft. - 6 ft. in height and has

definitely begun to influence shelter and light.

Z. Underplanting a nurse crop which will give definite over­

head shelter - a crop say 20 - 30 years old.

We know pretty well what happens regarding "X" for the first 20 years.

We have little or no local evidence regarding "Y". We have some evidence regarding "Z" or its equivalent as regards light conditions.

"X" is definitely extravagant with beech plants owing to failures.

It requires careful, skilled and timely attention. Given this, I think it could be made to work.

"Y" requires further elucidation. It may be the key to the problem and experimental plots for this purpose are now being laid down.

,fZ" may find favour with some but personally I do not like it. It has the advantage that you can get a good "take" and there is little frost damage but the development of the beech is unconscionably slow. They appear to get into a state when they exist in a healthy manner but refuse to put on height growth or at least a reasonable height growth. They tend to develop horizontally rather than vertically even with a very tenuous over­ crop.

75 This leads me to believe that beech is a tree that while it may require shade during the first few years after planting - I refer here to

Thetford Chase conditions - under certain conditions no shade or shelter is necessary for a quick "get away" - there comes a time, and it comes very quickly, when if normal development is to take place the tree must have its head well up in the open with at the most a side shade. The critic will say what about frost, and my answer is that far more damage has been done to beech growth by overshading than by frost in Thetford Chase. I believe it requires, disregarding soil, much the same treatment an Douglas fir in this locality.

Choice of Hurse

Of the four species which have been tried as nurses - Scots pine,

Corsican pine, European larch and birch - I like the results of birch and

European larch best. Definitely neither of the latter two are so exacting regarding timeous treatment.

Director’s Note - 13.6.49

Beech. (a) Results of work to date are unfortunately unreliable (as in the case of oak, etc., groups elsewhere) because of neglect, due in part to war conditions, at the most critical stage of development.

(b) As regards future establishment of beech, I am in favour of the method first quoted, using strong, well developed beech plants and necessary soil cultivation both for them and the nurse, particularly if the latter be birch, which would be my first choice, with European larch second (on suitable sites). But in choosing a nurse we must assume that in future timeous treatment will in fact be accorded.

76 KING’S FOREST

Chairman* a Inspection - Monday. 24th February, 1941

Compartment 100

The mixed plantation of Scots pine, Corsican pine, Douglas fir,

European larch and oak, P. 98, was inspected and the good growth of Corsican pine and Douglas fir was commented upon. The original intention in laying out this plantation was that the conifers should act as nurses, but it had been neglected and all the oak were now thoroughly suppressed or dead, whilst some of the largest Douglas fir are now 85 ft. in height. To substantiate a statement that the Douglas fir would be best on a short rotation of not more than 50 to 60 years, the Chairman was shown a dead

Douglas fir but he said that this might well be due to lightning and he instructed that the tree should be felled and the actual cause of death determined.

Having seen this plantation, the Chairman suggested that we might well try further planting of Douglas fip in similar situations, but insisted that they must be in a mixture and that both Scots pine and Corsican pine should be tried. The Divisional Officer stated that mixtures of 50/c

Douglas fir and 50/6 Scots pine had been planted in P.40 and that further extensions of this scheme were being made in P. 41. The Chairman said that with an equal mixture there might be a danger of the crop becoming pure

Douglas fir at a comparatively early age and it was imperative that the mixture should be maintained almost to the end of the rotation. He also stated that early thinnings were necessary in Douglas fir plantations, particularly in dry climates.

Chairman's Visit - 24th-26th November, 1944

Queen Mary Avenue - Compartment 30. P. 36.

The start of the Queen Mary Avenue, which has been maintained under management and put out of bounds to military training was inspected. The

Chairman explained to Mr. Osbert Peake what we hoped to achieve here, and it was agreed that a very good start has been made. Further work in relieving beech from some of the birch nurses will be necessary after one more growing season. A certain amount of work has already been done and

77 should enable the beech to maintain their present vigorous rate of growth.

Chairman's Visit - 5th-8th April. 1945

Chequers Belt - Compartment 69f. P. 19. Corsican pine

This Quality Class I stand of Corsican pine was inspected for soil and chalk conditions. The sand is 16 in. on top of chalk with flints.

Compartment 69d. P.10. Corsican pine.

In this case the Class I Corsican pine is growing on 12 in. of sand over chalk with flints.

Compartment 100b. P. 02. Corsican pine and Douglas fir with some Scots pine.

Seme fine Corsican pine and Douglas fir were seen here and a soil pit revealed there to be only in. sand over chalk with flints.

These three plantations, which constitute a sample only of a number at this forest, show that very good Corsican pine and Douglas fir can be grown where chalk or dead lime is very near the surface. No incidence of Fomes annosus was found in these plantations, although all had been planted on arable land. In each case, however, deep ploughing was carried out as preparation of ground for planting.

Chairman's Visit - 9th-llth May. 1947

The rabbits seem almost as numerous as ever in the Icklingham strip, and have done more damage than in previous years owing to the snow. They had even got into the first piece (fenced) of Queen Mary's Avenue, and I

saw one or two well-fed specimens. Why do we not deal effectively with this problem ?

It is doubtful whether we can do much with the Icklingham strip by beating up, and it may be necessary to let the trees grow up as they are, sort out the best of them, and be content with a high proportion of material suitable only for Celotex.

Chairman's Note of 16.9.47

With reference to Mr. Hopkinson's Notes of 1st September, 1947, I drove along the Icknield Way last week-end and found that rabbits are still numerous within the newly made enclosures, and teeming outside them. On that occasion I had the advantage of having Mr. Hopkinson with me. I observe from his notes that trappers, working from the middle of May to

78 the 1st September, have killed 3>500 rabbits. That period includes 90 working days, and (for 4 trappers), works out at an average of rather less than 10 rabbits per trapper per day, which is to my mind a ridiculous result. I would have thought that by the use of string nets great numbers, possibly 1,000 a week, might be taken in the initial period. Quite clearly the whole position needs looking into.

With regard to the second point in ny minute of 12.5»47, namely beating up the Icklingham strip, I am quite certain now that we shall be wasting time if we try to beat up the older plantations. The growth in

them, and recovery, have been quite extraordinary. I did not see the younger plantations which had been damaged, and offer no comment on them.

Chairman's and Director General’s Visit - 21.5.49

Compartment 30.

Queen Mary's Avenue - the response to thinning of the birch has been very satisfactory. A further thinning should now be carried out and the aim should be to avoid leaving birch crowns touching so giving the beech light and yet retaining some topcover.

The bircfc/oa^ belt on the east side must be opened up at once if the oak; are to be saved.

Ploughing of the narrow fire line behind the birch/oak belt should

cease as it has outlived its usefulness.

79 SWAFFHAM FOREST

Chairmans Visit - 21st July 1942

Compartments 18 and 20» Corsican pine P.24

Compartments 17 and 21. Corsican pine P. 23.

This Pickenham Corner block of Corsican pine was inspected. The whole

lot had been brashed since the last visit of the Chairman, and further, one of the 350 stems per acre plots had been set up in Compartment 18. The

Chairman saw this together with the types and quality of produce obtained from the felled trees. The Divisional Officer pointed out that although

on general examination this Corsican pine crop appeared to be eminently

satisfactory, when one came to the point of being critical and choosing

350 good stems per acre, the task was no easy one and the moderate propor­

tion of medium and small-sized trees among the 350 shewed that many of the largest trees had forked or otherwise malformed tops. The Chairman was doubtful whether stem increment above the normal can be anticipated for

some four or five years, in view of the drastic opening out of the canopy which may well have to be reformed before substantial increment is forth­

coming. It is of course this point, among others, upon which we are

seeking information. It is hoped that the Research Branch figures which

are to be completed at the end of this growing season will throw some

light.

1) On the allocation of the crop into girth classes.

2) the proportions of total increment put on by those girth classes.

P.36. Compartments 121 and 118. Corsican pine

P.37 Compartment 114, Corsican pine .

These Corsican pine compartments are growing well, but particular

interest centres in the roadside hardwood belt which in the case of

Compartments 118 and 120 was the last occasion on which conifer nurses were included in these belts. The belt alongside Compartment 114 and

across the road in Compartments 110, 111, 112 -and 113, Po37 is made up of

IOO70 hardwoods. The first mentioned was planted with Scots pine, birch

and some alder. The birch have grown very well indeed and now are in

the thicket stage and putting on a considerable annual shoot. The Scots pine too, are flourishing in those instances where they are not in

80 immediate danger of being suppressed by the birch. In these cases it is not of course intended to help the Scots pine but allow the birch to develop freely. The Chairman remarked that this sturdy development of the birch lent more weight to his argument that beech with birch nurses appears to be a satisfactory solution to the hardwood belt problem in East Anglia. The western halves of Compartments 118 and 119 consist of Corsican pine planted as very small but well rooted 1 + 1 plants. The Divisional Officer remarked that the forester had jibbed at planting these small Corsican pine, which were certainly very small and insignificant, but later fully came round to the view that small 1 + 1 Corsican pine are a satisfactory proposi­ tion on well-chosen sites provided the planting is carefully and painstakingly done and ensuing weeding is not neglected. The Chairman remarked that these plants were certainly as good as any on the area.

Commissioners1 Visit - 7tb/9th March. 1943

Compartment 47 is the Division's outstanding example of the shelter effect of a frost hardy species on a frost tender one. In P. 25/6, the area was planted purely with Douglas fir. These plants proved a hundred per cent failure or at least ostensibly so, for the following year the area was completely replanted with Scots pine which developed and which appeared to be the only species present until about 1932 when a sprinkling of Douglas fir showed itself among the Scots pine, which were obviously acting as nurses. From that time onwards a most interesting development has taken place. The Douglas fir, which originally cannot have been killed but must have had their shoots frosted off while their roots remained alive, developed strongly under the protection and shelter of the Scots pine, and by 1936 began in many parts of this and the adjacent compartment to take the initiative with the result that parts of the compartment have been transferred from pure Scots pine into Douglas fir with Scots pine. Even in those parts where the Scots pine are still dominant, many Douglas fir ere endeavouring to struggle through and throughout the area, silvicultural operations will be started as soon as possible to favour the Douglas fir component in this crop. After inspection it was agreed that the progress of the plantation is satisfactory.

Compartments 6 and 7. Scots pine. P.22

Particular attention was paid to this crop since it was the first Scots

81 pine block planted by the Forestry Commissioners to be thinned for the third time. The first light thinning consisted of a wolfing in the spring of

1936; the second or proper light thinning was done in the autumn of 1939; while the third thinning was carried out in October 1942. Mr. Price asked how soon gaps in the canopy would close up and the Divisional Officer said that a three-year period was anticipated though should the response of the plantation to the last thinning be particularly vigorous, a further thinning would be carried out earlier. It is the policy to deal with the planta­ tions on their merits insofar as labour conditions and other plantations as yet unthinned but requiring thinning allow. In this instance, this third thinning reduced the average number of stems per acre from 1584 to 976.

The cost per stem of felling, trimming and extraction to the produce dump was 35^ The cost of producing unpeeled pitwood was l/4d per hundred lineal feet, of five foot pointed stakes fd each and of 13/15 foot light army telegraph poles -gd each. Firewood logs and celotex are cut for 4/6cl per ton. The output per acre had been approximately 7,400 lineal feet and the excess of income over expenditure was £15. per acre.

Chairman’s Visit 24th - 26th November 1944

Line Thinnings in Pine Plantations in Eastern Division.

The Chairman agreed that for the period of the war thinning in the

East Anglian pine forests planted by the Forestry Commissioners may be on the basis of line felling. The possibility of this method being continued after the war as permanent peace-time policy is not ruled out and will depend on the information to be derived from wartime action and from further experimental areas which the Assistant Commissioner will arrange in other

Divisions, covering other species and other types of country.

Line thinning shall be in multiples of three, i.e. one line removed in three, or in six, or in nine, or in twelve. The condition and merits of the crop shall be the deciding factor as to which multiple shall be employed and the decision shall be made by the Divisional and District

Officers. The removal of one row in three shall refer to the' best crops and will probably entirely cover Corsican pine, while the removal of one row in twelve will be the method for the poorest types of Scots pine.

82 The decision to put into force this entirely unorthodox method of thinning was reached after careful consideration of three major points :-

1. The necessity of getting out of Forestry Commission young

plantations a reasonable proportion of large-sized pit

props.

2. The need to speed up the operation from a silvicultural

point of view, i.e. to cover more acres with the same man­

power force.

3. The absolute necessity of reducing production costs from the

time the tree is felled, i. e. obviating the carrying out of

stems etc.

Experiments have been set up on the basis of removal of one line in three and statistical data on these plots has been provided by the Chief

Research Officer. The terms of reference of his statistical analysis were to see how far line thinning departs from the accepted present practice of selective thinning. A thinning restricted to every third line obviously on the average removes one third of trees which would by the orthodox method be left to go on for final crop selection. The question was, therefore, whether the two rows left out of each three would contain sufficient trees and also sufficient in proper distribution to form the final crop. The investigations conducted by the Chief Research Officer with the help of the Divisional Officer's staff were restricted to good- class and good-type Corsican pine P. 26 (Compartment 76 Elveden Beat), poorer Corsican pine P. 25 (Compartment 93 Methwold Beat), good Scots pine

(P. 24 Compartment 18 Downham Beat) and poor Scots pine P. 24 (Compartment 37

Downham Beat).

For Corsican pine it is assumed that 108 trees per acre will be needed in the final crop, that is one tree is every square 20 ft. by

20 ft. For Scots pine 150 trees per acre will be needed, being spaced as to one tree in each square 17 ft. by 17 ft. The statistics worked up by the Research Branch from the above-mentioned plots showed that 590 suitable trees were left in the good Corsican pine plot after a one in three thinning, giving a selection factor of approximately 5.9. In the poorer type Corsican pine 273 satisfactory stems were available, giving a selection factor of 2.73. After thinning, the better Scots pine showed 200 trees

83 available giving a selection factor of 1.3 while the poorer Scots pine gave a selection factor of 1.1 only, there being only 168 trees left to provide the final requirements of 150 per acre.

The conclusions drawn from the above data were that with a high selection factor no damage is done to the crop by the removal of one row in three, but that with a 1.1 selection factor given by poor Scots pine there is no room whatever to remove anything by line thinning. A line thinning in these circumstances would cause serious silvicultural detriment to the crop. Further, in the poor crops not only are badly-needed good trees removed, but the opportunity of removing bad trees from the crop is the denied since to remove these, in addition to doing/one-third removal by line thinning, would cause abnormal and highly undesirable gaps in the crop.

The plantations dealt witfi/^a line-thinning basis are to be watched carefully as to their future development and control areas normally thinned on a selection basis are to be maintained adjacent thereto.

In those cases where the line thinning is a one in six, or one in nine, or one in twelve, selection thinning shall be carried out in the rows between the line fellings. In these instances the lines felled are primarily intended to facilitate extraction and thereby lessen the costs of production.

As an alternative to line thinning, clearfelling of certain areas was considered but it was decided that in the interests of the country’s future timber supply, it is preferable to keep what we can and make the sacrifice, if any, in quality.

The Chairman promised Mr. Williamson, T.P. D. Division 5 Divisional

Officer, 100,000 cu.ft. from line thinning, this being the next six-monthly requirement of T. P.D. in these parts. The matter of further thinning along these lines will require fresh review sifter that date.

Chairman*s Note to Mr. Connell’s statement (Addendum I) which is

approved. - 6.12.44.

"Line thinning has two weaknesses:

1. It removes trees which should be left.

2. It fails to remove trees which should be felled.

84 In good crops these weaknesses are relatively insignificant "but in poor pine crops and especially those which have suffered Tortrix damage they are serious. Because "Tortrixed" trees are often the largest close line-thinning does not provide any more, if as much, large material than an orthodox thinning. In proportion as the crop is poorer, therefore, line-

thinning should be used less and less as a method of thinning and more and more as a method of providing accesses for the removal of felled trees”

85 HISTORY OF THETFORD, KING’S AND 3WAFFHAM FORESTS

APPENDIX II

Superior Supervision

Year Conservators Divisional Officers District Officers

1923 W. L. Taylor R. G. Forbes

1924

1925 W. H. Lovegrove

1926 Vv'. H. Guilleband C.E.L. Fairchild

1927 A. P. Long

1928

1929 W. A. Muir

1930 H. M. Steven

1931

1932

1933

1934 E. Wynne Jones

1933 J. MacDonald c. A. Connell

1936 c. A. Connell

1937 c. A. Connell

1938 c. A. Connell - J. Q. Williamson

1939 c. A. Connell - J. Q. Williamson

1940 C. A. Connell G. D. Rouse

1941 G. D. Rouse

1942 G. D. Rouse

1943 G. D. Rouse - Denman

1944 &• D. Rouse - Denman

1945 F. E. B. DeUphaugh Denman,Cheesewright

1946 A.D. Hopkinson D. Mackay, Denman Gonder

1947 G. V/. Backhouse D. Mackay - Conder

1948 D. Mackay - Conder F. Weston

86 Year Conservators Divisional Officers District Officers

1 % 9 G. W. Backhouse G. F. Ballance D. Mackay

S. W. Rogers

- J. L. Davidson

1950 D. Mackay

3. W. Rogers

J. L. Davidson

Notes (a) In addition to the above a large number of junior District

Officers have been attached to the Thetford areas, temporarily

for training.

(b) Owing to the very numerous changes in the dispositions of Beats

with the constant expansion of the Forest area, it is not

possible to compile an accurate list of past Forester Super­

vision.

87 HISTORY OF THETFORD, KING-'S AMD SWAFFHAM FORESTS.

APPENDIX III

RAINFALL - LYRFORD SCHOOL

FOREST YEAR

Month '47 •48 ’49 ’50 ‘51 Average

October 1.35 .30 2.06 3.74 .60 1.61

November 3.64 1.47 1.33 2.24 4.65 2.66

December 1.88 2.70 1.52 1.86 2.10 2.01

January 2.19 4- 38 1.11 1.01 2.94 2.33

February 1.11 .74 .83 3.18 2.75 1.72

March 4.48 .59 .91 .39 3.61 1.99

April 1.46 1.64 1.86 2.34 3.24 2.11

May .63 4.15 2.03 1.87 1.69 2.07

June 2.82 2.59 .80 2.52 1.25 1.99

July 1.23 2.87 2.39 6.99 1.06 2.91

August .10 2.65 2.20 3.11 2.95 2.2

September .98 1.66 1.54 4.26 2.46 2.18

Totals: 21.87 25-74 18.58 33-51 29-30 25-8

Monthly average = 5-16 inches

88 APPENDIX III (Contd)

SUNSHINE - LYNFORD SCHOOL

FOREST YEAR

Month '47 •48 '49 *50 '51 Average

October 79.7 107.0 75.6 104.2 104.0 94.1

November 51.8 83.7 59.2 61.9 39.5 59.2

December 44.4 24.5 56.1 50.6 37.0 42.5

January 58.2 42.6 59.1 42.9 53.6 51.3

February 26.0 66.4 101.6 77.5 58.8 66.1

March 58.4 181.3 104.0 117.7 100.7 112.4

April 152.7 194.4 190.5 148.6 177.7 172.8

May 207.6 245.0 206.3 144.6 179.0 196.5

June 163.3 131.5 230.2 247.1 253.9 205.2

July 169.4 194.6 212.9 183.8 208.5 193.8

August 281.5 127.2 213.1 179.1 179.4 196.1

September 151.7 117.8 161.7 121.1 114.6 133.4

Totals: 1444.7 1515-5 1670.3 1479.1 1506.7 1523.4

Monthly Average = 126.9 hours

89 01476232

m m m HEIGHT IN FEET GROWTH P. 7 f A R A f 7 P. HISTORY SWAFFHAM OF THETFORD OF bihmission FORESTS KING'S HEIGHT IN PEE1 GROWTH EUROPEAN LARCH EUROPEAN HISTORY OP THSTPJQRDOP HISTORY ORESTS HISTORY Off THiST-B'QKD, KIHG-’ S AITD SlVAFFHAM

m miss ion

\rW H HEIGHT IN FEET GROWTH AND SWAFFHAM FORESTS SWAFFHAM AND ITR FTEFR, KING’S OFTHETFORD, HISTORY THETFORD KING’S SWAFFHAM F

m ission

H i n t W U t g EIGHT IN FEET GROWTH OF GROWTH SCOTS FINE SCOTS HISTORY OF HISTORY SWAFFHAM FORESTS SWAFFHAM HBTFORD .Qimriksioii KING'S ■SWAFFHAM FOREST

LECEND

Planted Atea. forestry Commission3 o i/ n d a n y f yean boundaries S c a l e