COPPICE SILVICULTURE: SOME ALTERNATIVES AND APPLICATIONS

Transcription

1 COPPICE SILVICULTURE: SOME ALTERNATIVES AND APPLICATIONS Ralph D. Nyland Department of Forest and Natural Resources Management SUNY College of Environmental Science and Forestry Syracuse, NY Nyland 2009 All rights reserved Use of all or parts of these class notes prohibited without express consent of Ralph D. Nyland Background reading: Chapter 9, in Nyland, R.D Silviculture: Concepts and Applications. Waveland Press. Long Grove. IL. 2ed. Sources cited: Aldrich 1963 ArborGen, LCC FlexStand System Guide. ArborGen LCC, Summerville SC. Christersson, L., L. Sennerby-Forsse, and L. Zsuffa The role and significance of woody biomass plantations in Swedish agriculture. For. Chron, 69(6): Fowells, H.A Silvics of Forest Trees of the United States. US For. Serv. Agric Handbk Hammill and Moran 1986 Hawley, R.C The Practice of Silviculture. John Wiley & Sons, Inc. NY. 3ed. Hawley, R.C., and D.M. Smith The Practice of Silviculture. Wiley. NY. 6ed. Matthews, J.D Silvicultural systems. Oxford Univ. Press., Oxford. Patton, D.R Wildlife Habitat Relationships in Forested Ecosystems. Timber Press. Portland, OR. Porter, W.F Integrating wildlife management with even-aged timber systems. Pp in Managing Northern Hardwoods. R.D. Nyland, (Ed.). SUNY Coll. Environ. Sci,. and For., Fac. For. Misc. Publ No. 13 (ESF 87-02) Soc. Sm. For. Publ. No

2 Consider an example Aspen silviculture with attention to wildlife (grouse) habitat management Natural ranges for aspen and ruffed grouse overlap 2

3 Grouse benefit from aspen stands at different stages of development feeding on catkins and buds US Forest Service and using dense stands for cover and other life essentials 3

4 also, aspen stands may have high volumes of good fiber suitable to many uses and we can regenerate them over large areas readily by coppice methods 4

5 But note this - while good sites produce high volumes - poor sites and overmature stands have limited commodity potential Overmature and decadent poor for commodities also not necessarily great for ruffed grouse 5

6 So what age for 5000/acre Best conditions for grouse... This stand has high potential as grouse habitat... 6

7 What age for 20 feet tall 18 ft 12 ft 6 ft 7

8 Note this how habitat quality shifts with stand age Porter about half a century 8

9 Also an interspersion of condition classes best Porter 1987 with different conditions in close proximity interspersion of requisite conditions over space and time 9

10 And close proximity means within 500 feet... a balance of age classes across the landscape Not a goal with aspen 500 ft Adapted from Patton

11 Stacy McNulty establishing different age classes in close proximity but not likely to this extreme 11

12 probably more like this... well suited to mechanized harvesting 12

13 ... and fiber production goals US Forest Service clearfelling the copse to establish a new age class 13

14 US Forest Service relying on root suckers to restock the stand US Forest Service with this outcome (after 11 years) 14

15 but how to know when to call a stand mature The culmination of m.a.i. 15

16 A reasonable match Peak m.a.i. Porter within the maximum targeted time... melding fiber production using coppice methods, with maintenance of good habitat for ruffed grouse 16

17 Now back to a consideration of coppice silviculture in general as well as making it suitable for coppicing aspen with wildlife habitat management Coppice system advantages SIMPLE - certain regeneration - high level volume production - short rotations, with quick payoffs (e.g., volume and grouse with aspen) - cutting area any size and shape - species composition predictable - few health risks with short rotations 17

18 A good scheme for fiber production and grouse habitat management Coppice system disadvantages - small diameter products (mostly) - useful with few species (hardwoods) - frequent site disturbance with short rotations - yields little sawtimber - aesthetically unpleasant (the reproduction method) - grazing / browsing must be excluded - shoots arising after late summer cutting susceptible to frost damage 18

19 ... and if by sprouting, you must deal with the clumps Consider an alternative 19

20 Consider an alternative Coppice with standards selected trees (perhaps of seed origin) left to grow to large size An alternative START STANDARD STANDARD STANDARD keep selected trees at uniform and wide spacing 20

21 Coppice with standards selected trees (perhaps of seed origin) left to grow to large size with coppice growth maintained beneath them then coppice the rest Like this after the cutting leaving only the standards 21

22 An alternative Leading to a 2-aged stand as the coppice shoots develop START STANDARD STANDARD STANDARD.. or like this with oaks From: Matthews

23 coppice with standards in aspen a two-aged stand 23

24 Second entry Same CUT ALL process EXCEPT repeated SELECTED through time NEW STANDARDS STANDARD STANDARD STANDARD as a new age class develops by coppice growth Or as a new approach for coppice-with-standards (Standard) (Coppice) ArborGen FlexStand Schematic perhaps implemented as suggested by ArgorGen with its FlexStand strategy ArborGen

25 something like this repeated indefinitely Or have standards of multiple ages go first to coppice with standards each time keeping some of the old standards, plus adding new standards from the understory growth To get this From Hawley

26 Called COMPOUND COPPICE producing an uneven-aged stand An alternative COMPOUND COPPICE 26

27 Hawley and Smith 1954 like this from above Coppice with standards Silvicultural requirement (historic) -the STANDARDS should be fast-growing species may mean shade-intolerant ones - the coppice UNDERWOOD may need to be at least moderately shade tolerant 27

28 Or Or keep the standards at only rather wide spacing... like this to improve light in the understory 28

29 To increase the number of standards - retain existing standards as a seed source if old enough to produce seed - clean to keep young potential standards free to grow - beat up the stand (reinforcement planting) but plant large seedlings as a wide spacing - thin selected coppice clumps to a single stem and keep the favored sprout for multiple rotations as a seed source... periodically establishing some new trees to become future standards 29

30 ... or deciding how to convert sprout clumps to single-stem standards for the future or with some species just accepting a few sprout clumps of low origin Now an entirely different kind of coppice system for BIOMASS PRODUCTION 30

31 Note the advantage of willow Christersson et al as a mini-rotation biomass crop When planted at close spacing... and managed for mini-rotation periods 31

32 T.A. Volk... started from unrooted cuttings 32

33 Swedish double-row planting method D. Robison Coppiced after the first year to promote vigorous sprouting from the stools... with the shrub willows producing multiple vigorous sprouts after the 1 st -year cutting 33

34 ... like this... and rapid growth 34

35 But when to end the rotation... Nissen 2001 regenerating the copse at the culmination of m.a.i. for biomass with a harvester like this one 35

36 The cutter head Producing chips like this for biofuels 36

37 ... and cutting low stools... they will sprout again for another rotation 37

38 ... providing repeated crops at short rotations... woody biomass (at least 10 dry tons/ac/yr) 38

39 After Nissen 2010 Should we clone it if it had antlers, I d do something 39