The development of modern in New Zealand

1997 brings the 50th anniversary of the New Zealand Research Institute (FRI). Over the time it has been in existence, FRI has been involved in a wide spectrum of research including geneticshee breeding, soils, physiology, and forest health, and utilisation. The research in each of these areas has been instrumental in shaping the way that the forest sector has evolved in New Zealand. The following article looks at one particular component of FRl's research which has brought about the silvicultural practices which are common today. The article is an extract from a book by John Kinin- month, "A History of Research in New Zealand". The book will be launched in conjunction with the 50th Anniversary of FRI on April 1, 1997. (Editor) Two men sampling a stand of Douglas-fir (Pseudotsuga rnenziesi.)in the South Island. The technical and economic basis for the Photo: NZFRI development of modern silviculture of Director of Research, set new priorities for flavour', and he set up a new research radiata pine had its beginning in 1961 research. One of the changes was to give group, that became Economics of Silvi- rn- h 0 D nn' ' hard hen he new We i~tviteALL I)euple with an inteu comme~lces.AndyKirkland will open in thefumrt ~IZ~LL.~~I+II,an3 their part~zerd, @ occasion with a definitive address to participate i~zall Jrrlilee event./. in wMch he wiU make poblic fbr the first time his personal views on the public and private ownership of , their creafion, manage- ment, and marketing. Speakers from New Zealand, Asia, Australia, North, and South America will follow. giving their views on research, financing forestry, and future markets. The those who have worked for the cultural highlight of the week wiU be Institute over its 50 years will be the performance of the Auckland unveiled by Priestley Thomson, the Philharmonic Orchestra in the Redwood Orove, a unique event that Experiment Station. The AGM of the all participants iuld their partners will k Institute of Forestry will be held on be keen to attend. campus on the afternoon of the Reunion, and the day's festivities will culminate in a 'starlight' dinner and dance. FRI WTH JWILEE INTERNATKNM !; !; FORE57 RESEARCH CONFERENCE The 50th Jubilee Conference will address some of the key issues facing the forest industries over the next A sector-wide function during which decade. The purpose is to provide everybody involved with, a depen- some thot@epmvoking presentation dent on fomtry will haw the appmt- and an initial forum fot debate on unity to participate. Lindsay Poole, matters which will helpshape forestry the o~tliving ex Directm-OeRend in the years to come. Prestigious of ~orestswill unvcil a naenmid on speakers from New Zealand and 1 rhePZucanrpusrec~~grhelOOth overseas have been invited to par- I annivasary of the firs( Government ticipate. : plaaings. The Prim M~nister of the F day will then fonnally open the )!.. hnction at the Rotma CoaverrCion 7- For more information contact , Cenae fellowed by the prese~sazlon I of the Forest Research Pioneer Freephone 0800 737 327 ving force. The first task of the group was a cost analysis and profitability forecast of alternative silvicultural regimes, coupled with analysis of the effects of site vari- ables such as topography, site quality and distance from markets. An initial economic model was devel- oped to serve as a framework for testing the effects of changes in individual cost components. Fenton had worked closely with Conservancy whilst he was a Technical Officer at Conical Hill and had published an economic analysis of tending in Southland with C.H. Brown soon after coming to FRI (Fenton and Brown, 1963). This paper pointed out that tending had to be 'timely' for the costs to be justified and also identified that log size and sawing costs have a major effect on the econom- ics of forestry. As sawmilling was the principal utilisation outlet, there was a need to define the optimum size of log, and to relate log size distribution to saw- ing costs in different types of sawmill, as well as to production costs such as tend- ing and harvesting. It was known that thinning and prun- ing practices varied greatly between regions, and where utilisation studies had A tree root survey of six-year-old radiata pine was carried out by NZFRI at Tikitere Forest Farm been carried out, clear timber or clear Block Q in 1979. Pictured is a general view after medium pruning. Photo: NZFRI veneer yields had been disappointing, usu- sawing studies from these were some special analysis was required. It also ally because of lateness of treatment. described by Brown (1965). Later studies avoided the personal bias inherent in allot- These issues were covered in the first thin- provided information on second-crop ting grades, which might vary within and ning and pruning symposium held at FRI tended stands and sawlogs from produc- between studies. (Brown and Bunn, 1963) which "dis- tion thinning. An important innovation Over the next decade intensive effort cussed the current state of knowledge, introduced in early grade studies at FRI went into collecting detailed information practice and progress in development of was to record the defects in each board on all facets of forest growing, harvesting thinning and pruning forests of exotic rather than merely assigning an overall and sawmilling for use in economic mod- , with particular reference to Pinus grade based on current grading rules (Fen- elling for, as Fenton said in his 1966 radiata". ton, 1966). The resulting database could paper, the models were only based on the Among the large number of presenta- be reworked if grading rules changed or if (relatively limited) data available at that tions from FRI and industry was one by time. By the late 1960s, the research team Fenton and his co-workers, Wink Sutton included John Tustin, Ryde James and and John Drewitt, on clearwood yields Mat Grainger, as well as Fenton and Sut- from radiata pine which showed the ton. Several important field studies were importance of log size and its relationship underway, including studies to examine to the diameter of the knotty core. Another the effect of initial spacing on branch size, paper at this conference by Fenton was effects of the number of pruning lifts and entitled Returns from Tending. In this the proportion of green crown removed on paper, based on his earlier Southland work the height and diameter increments of and data from a central North Island land- selected pruned dominant trees, and the use study, he concluded that "tending pays yields and economics of production thin- very handsomely indeed". ning. Much of the accumulated experience Sawing studies were an effective was embodied in the silvicultural propos- means of determining the effects of silvi- als for production of board grades which culture on log quality (e.g., size of knots, became known as the direct sawlog whether knots were live or dead, yield of regime (Fenton and Sutton, 1968). This long-length clears) and value. trees regime involved early thinning to waste, in the forest and dissecting nodes was an thus avoiding the disadvantages of pro- alternative means of checking for the duction thinning, and a three-lift pruning depth of the clearwood sheath. As was to 18 to 20 ft (5 to 6 m). It was recognised pointed out at the symposium, there was a that over ,80% of the net value of final- dearth of suitably-tended stands in state crop trees is in the two bottom logs. With forests from which to check the effects of NZFRI research l~asled to improved breeds of the butt log pruned, emphasis needed to be tending on clearwood yields. The best t'tnus radwta. I nls pnoto was tauen In was. placed on the characteristics of the second were found in smaller private forests, and Photo: NZFRI log when selecting crop trees. Advantages

- 18 N.Z.FORESTRY FEBRUARY 1997 were also seen in utilising the often uni- nodal habit of radiata pine to achieve worthwhile yields of factory grade (clear cuttings) from the second log. A second pruning and thinning sym- posium was held in 1970 (James et al., 1970). By then there had been important changes in industry, in particular a greatly expanded planting programme, an increasing emphasis on radiata pine, and - in practice - a much higher proportion of stands being pruned. Among the 60 papers presented were ones from FRI showing that live branches increase in diameter in response to thinning (James and Tustin, 1970), that branch size increases as initial spacing increases (Sut- ton, 1970), and (once again) that produc- tion thinning is unlikely to be profitable (Tustin, 1970). Another subject that came up here, as it had over the years, was the lack of a sizetprice gradient for sawlogs, Waipa sawmill workers at the Waipa laminating plant in 1960. Photo: NZFRI making it difficult to give full weighting to the advantages of a regime that yielded well established although, with the com- involved and the vast amount of data larger logs. plex interaction of so many variables, becoming available, better tools were Within the next few years, Fenton defining specific regimes required con- needed to assist the forest manager in (with various co-authors) had published a siderable further effort by way of field tri- decision making. Computer-based model- large number of papers giving a compre- als and analyses. ling was suggested by Russell Grant, one hensive coverage of the economics of There was still considerable scepticism of the members of the group involved in growing radiata pine including the impli- among forest growers about some of the economic analysis. cations of growing for different markets, procedures that were shown to be desir- This approach was successfully used e.g., log export. These papers were pub- able economically and the Director Gen- by the Radiata Pine Task Force set up in lished together in two of the 1972 issues eral of Forests expressed concern at the 1979 with FIU and industry input and led of the New Zealand Journal of Forestry proliferation of different silvicultural by Wink Sutton. Industry funded an inter- Science (ex. Fenton and Dick, 1972). By regimes in use. Researchers realised that, active PDP 11/34 computer and the task then the basis of modem silviculture was with the large npmber of variables force developed the Silvicultural Stand I d Model (SILMOD). With the model it was possible to simulate the growth of a hectare of radiata pine, together with the harvesting, transporting and sawing of that stand, in a few seconds, a task that had previously taken weeks (Whiteside and Sutton, 1983). An important advantage was that the sensitivity of output to any one variable could be easily tested, and users could enter their own specific cost figures. This model helped to consolidate the era of 'new crop radiata', the implica- tions of which had been well described in a paper on the nature of the resource by Harry Bunn (1981). SCMOD was replaced later by STANDPAK based on work of the Con- version Planning Project Team (Kinin- month, 1987). In this model the earlier work was extended, with some functions being refined and others added, including a newly-developed set of standard log grades (Whiteside and Manley, 1937) and a range of processing options. STAND- PAK is now widely used throughout the forest industry. An IUFRO symposium, New Approaches to Spacing and Thinning in Forestry, was held in Rotorua A NZFRI trial at Whaka Forest in 1981. Some of the legumes in the spaced-plant trial eight months in 1989 (James and Tarlton, 1989). This after planting out. Photo: NZFRI provided a forum for a review and dis-

N.Z. FORESTRY FEBRUARY 1997 19

cussion of regimes with a composite audi- ence from both the New Zealand industry and overseas. The introduction of silvicultural prac- tices involving lower initial stocking and early thinning to waste opened up new opportunities for and have allowed it to grow ever since (Knowles, 1991). A symposium held at FRI in 1986 reviewed the then state of knowledge from research and its application by indus- try (Maclaren, 1986). The agroforestry research programme pioneered research into the planting of trees on fertile farm sites, a trend which now accounts for a high proportion of total new planting at more than 50,000 ha per year. The bene- fits of combining farming and forestry on these sites were demonstrated by a series of trials. This included the world-famous Tikitere trial, established jointly in 1973 between FRI and the Ministry of Agri- culture and Fisheries. Techniques first applied in agroforestry have been exten- ded to improving the productive capabil- ity of shelterbelts, and special models have been developed to handle the com- plex interaction between the forestry and agricultural components of agroforestry. Trials on traditional forestry sites demon- strated the benefits of oversowing with maku, which restrict weeds while provid- niques are now widely applied. grasses and legumes, including Lotus ing soil nutrients and forage. These tech- Contact with industry has been

A vessel at Mt Maunganui Wharf, with large stacks of logs in the foreground. Photo: NZFRI

22 N.Z. FORESTRY FEBRUARY 1997 strengthened during the last decade by the Brown, G.S. (Compiler); E.H. Bunn (Editor). setting up of a research cooperative and a 1963: Pruning and thinning practice in collaborative now joined into the Forest New Zealand. NZ Forest Service. FRI Symposium No. 3. and Farm Plantation Management Coop- Bunn, E.H. 1981: The nature of the resource. erative. This provides industry input to NZ Journal of Forestry 26(2): 162-99. applied research while the main thrust of Fenton, R.T. 1966: A timber grade study of the programme continues to be the design, first rotation Pinus radiata D. Don from installation and measurement of large- Kaingaroa Forest. NZ Forest Service scale silvicultural trials. These trials have Technical Paper 54. been established on a wide range of sites, Fenton, R.T.; C.H. Brown. 1963: An economic and inclusion of the results into manage- analysis of tending Pinus radiata in South- ment tools such as STANDPAK will fur- land. NZ Journal of Forestry 8(5): 793-81 3. Fenton, R.T.; M. Merle Dick. 1972. Profitabil- ther strengthen the value of this package ity of radiata pine for the log for the many forest managers and planners export trade - on site index 80. NZ Jour- who are now licensed users. One of the nal of Forestry Science 2(1): 69-99. major recent applications of STANDPAK Fenton, R.T.; W.R.J. Sutton. 1968: Silvicul- by forest growers has been the accurate turd proposals for radiata pine on high- scheduling of stands for pruning and thin- quality sites. NZ Journal of Forestry 13(2): ning, facilitated by the development of the 220-8. EARLY growth model (West et al., 1982) James, R.N.; J.R. Tustin. 1970: Diameter and functions to predict diameter over response of branches after thinning in radi- stubs (Knowles et al., 1987). In recent ata pine. NZ Forest Service. FRI Sympo- sium No. 12. years, there has been a change in the pa\- Peter Hall (NZFRI technician) high pruning James, R.N.; W.R.J. Sutton; J.R. Tustin; E.H. tern of forest establishment with an P. radinta at Kaingaroa in 1988. Photo: NZFRI Bunn. (Compiler and Editors). 1970: Prun- increasing number of small private grow- ing and Thinning practice. NZ Forest Ser- ers. A Radiata Pine Growers' Manual has Conversion of farmland is expected to vice. FRI Symposium No. 12. been produced which is helpful to all account for an increasing proportion of James, R.N.; G.L. Tarlton. (Editors) 1989: New growers but especially those new to the new planting and this increases the matrix approaches to spacing and thinning in industry (Maclaren, 1993). of silviculture/site interactions that must plantation forestry. Proceedings of a Increasing effort is pow being devoted be understood. It also increases the need IUFRO symposium. Ministry of Forestry. to research on the silviculture of Douglas- for refinement of whole-farm planning to FRI Bulletin 15 1. optimise the contributions from the agri- Kininmonth, J.A. (Compiler). 1987: Proceed- fir which has emerged as a strong second ings of the Conversion Planning Confer- to radiata pine in planting for the future. culture and forestry components within ence. Ministry of Forestry. FRI Bulletin This and other changes in the forestry sec- the diversity of spatial patterns that are 128. tor, such as the increasing interest in the possible. Knowles, R.L. 1991: New Zealand experience growing of particular clones or breeds of with silvopastoral systems: a review. For- radiata pine for specific end products, will References est Ecology and Management. 45: 251-67. Brown, G.S. 1965: The yield of clearwood require considerable research to determine (FRI reprint 2422). from pruning: some results with radiata Knowles, R.L.; G.G. West; A.R. Koehler. growth and quality implications and to pine. Commonwealth Forestry Review provide new models to help industry. 1987: Predicting diameter-over-stubs in 443): 197-221. pruned stands of radiata pine. Ministry of Forestry. FRI Bulletin 12. Maclaren, J.P. 1993: Radiata pine growers' FRI's 50th Jubilee 'Forestry Festival' manual. FRI Bulletin 184. Maclaren, Piers (Editor). 1986: Proceedings of An evening performance by the Auckland marks the 100th anniversary of government the Agroforestry Symposium. Rotorua. Philhamonia Orchestra under the Rotorua involvement in plantation forestry in New November 1986. Ministry of Forestry. FRI Redwoods is expected to be the highlight of Zealand. We are inviting all people who Bulletin 139. the Forest Research Institute's 50th Jubilee have an interest in the industry, be it as Sutton, W.R.J. 1970: Effect of initial spacing celebrations in April. growers, investors, contractors, manufactur- on branch size. NZ Forest Service. FRI Planning is well-advanced for the four- ers, exporters, or consultants, to join with us Symposium No. 12. . day "Forestry Festival", which will be a mix- in acknowledging the achievements of the Tustin, J.R. 1970: A review of first utilisation ture of informal opportunities for old friends sector to date, and to plan for some of the thinning, for other than minor forest pro- to meet and refresh shared memories, and challenges and opportunities that face us as duce, of tended radiata pine stands. NZ Forest Service. FRI Symposium 12. thought-provoking presentations from well- we move into the 21st century." The four-day event includes the FRI West, G.G.; R.L. Knowles; A.E. Koehler. known New Zealand and overseas speakers 1982: Model to predict the effects of prun- on the future of forestry. Reunion, a "Forestry Celebration Day" and ing and early thinning on the growth of Over 1000 people are expected to gather a two-day international conference. The lat- radiata pine. NZ Forest Service. FRI Bul- in Rotorua for the jubilee and centenary ter two events will provide a stimulating letin 5. events. Several hundred expressions of inter- forum for debate on issues concerning the Whiteside, I.D.; B.R. Manley. 1987: Radiata est have been received from forestry per- future of plantation forestry in New Zealand. pine resource description by log-grade sonnel as far afield as Myanmar, Singapore, Distinguished New Zealand and interna- specifications. In: Proceedings of the Con- Laos, Chile, and Canada. tional speakers have confirmed their atten- version Planning Conference. Rotorua "Some 2000 people have worked for FRI dance at the Jubilee forum. 1986. Ministry of Forestry. FRI Bulletin since it began research operations in 1947, FRI would like to hear from anyone 128. and we are expecting many of those ex-staff interested in attending any or all of its Whiteside, I.D.; W.R.J. Sutton. 1983: A silvi- members to re-converge on Rotorua," said Jubilee events: for more information please cultural stand model: implications for radi- John Groome, Jubilee Convenor. phone 0800 737 327. ata pine management. NZ Journal of "By a lucky coincidence, 1997 also Forestry. 28(3): 300- 13.

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