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.