Understanding Silviculture

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2 Understanding Silviculture The Art and Science of Growing a Forest Brian Knox President Jonathan Kays Extension Specialist Natural Resources

3 Silviculture The art and science of tending a forest Art: Developing prescriptions that meet the goals and objectives of the forest landowner Note* (there is no one correct management plan for any given property) Science: Identification and assessment of trees and site characteristics, data collection and application of treatment prescriptions.

4 Silviculture Simulates a controlled natural Allowing us to: disaster designate how and when forests are regenerated change forest structure/composition improve habitat and diversity Sustainably manage forest resources

5 What Is Sustainable Management?

6 The management that meets the needs of today, without compromising the ability for future generations to meet their needs.

7 Imitate nature and hasten its work, such is the maxim of silviculture Louis Parade ( ) Director of the Forestry School of Nancy, France

8 Harvest studies show high quality sawtimber production was sustained: Pennsylvania West Virginia New York 38% of the time 27% of the time 38% of the time (Finley et al 1997; Fajvan et al 1998; Nyland pers. Comm)

9 In Other Words: 60-70% of the time Our Harvests are not Sustainable

10 Sustainable Silviculture Requires Planning

11 It is a Process That Includes: Careful identification of landowner objectives An inventory of resources Analysis: health, vigor and structure Development and implementation of the management strategy to be used Periodic re-evaluation of the implemented strategy.

12 Inventory (what tools are in the forest toolbox?) Vegetation: Species Size/age Distribution Quality Site: Aspect Soil Moisture History

13 Site: The combination of biotic, climatic, topographic, and soil conditions of an area; the environment at a location. Southwest Aspect Northeast Aspect

14 Site is More Important than the Vegetation It is more fixed It is more stable It is more easily defined Reflects disturbance Strip mine (extreme) Pasture (subtle) Harvesting (either)

15 History

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22 Forest Inventory & Analysis Quality of Site Composition Trees /acre Size & Types Age Growth Rate Age Distribution (even or uneven age) Products available

23 Stand Age Diameter is a poor indicator of age

24 Increment Borer takes a tree s medical history

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27 Tree Scale Stick Measure tree diameter and number of 16-foot logs How many board feet in a tree VideoBiltmore.html

28 Basal Area

29 A prism can be used to determine the BA and stocking of trees in the stand

30 180 STOCKING CHART Basal area (sq ft per ac) B C A C Mean Stand Diameter 8 7 B 6 5 A 20 (after Leak et al. 1969) Trees per acre

31 GUIDE LINES A-LINE 100% relative stand density (RSD); maximum crowding B-LINE Generally 60% RSD; site fully occupied, but trees are relatively free of competition C-LINE Generally 45% (30 to 60% RSD, depending on stand age); stand will gain B-line stocking within 10 years

32 180 STOCKING CHART Basal area (sq ft per ac) B C A C Mean Stand Diameter 8 7 B 6 5 A 20 (after Leak et al. 1969) Trees per acre

33 Stand development: Year 1: 10,000 stems/ac Year 15: 1,000 stems/ac

34 A B Site Index brings it together! * By measuring total height and age * You get site index, the height of a tree at 50 years old * The taller the tree, the more productive the site.

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36 The forester can change his environment with the ax

37 Systems (Types) of Management Even-age One age class ~ Clearcut, Shelterwood, Seed tree Uneven-age More than one age class ~ Selection, Group selection

38 Systems (Types) of Management % Canopy Removed * Even-aged Management - Clearcut - Seed tree - Shelterwood - Crop tree release * Uneven-aged Management - Single or group selection - Two-aged * Intermediate Treatments - Thinning & Crop tree release CC Seed tree Shelterwood Two-aged Selection

39 TYPES OF CUTTINGS Intermediate Improvement Harvest

40 INTERMEDIATE CUTTINGS (TSI) Immature Stands!! Thinning Maintain/Improve Growth Rate Too many trees Early in stand development (loss of growth) Usually delayed until merchantable products (firewood/pulpwood)

41 Performed when: Crowns interlace Dead or dying trees Trees limby or crooked Diseased or injured Crowded in clusters Concentrates Growth On The Desirable Trees

42 These trees grew 40 feet apart, but they are the same age

43 Crown Touching Release

44 Free-to-grow (FTG) classes

45 Response to Crown-Touching Release Dbh of measured trees: inches 4.5 Growth rate (inches per decade) Number of sides released (FTG) Adapted from Perkey and Wilkins 2001

46 4-sided crown release

47 One Objective of thinning: Produce high quality wood with benefits for wildlife

48 Identify the Trees in the Stand That Meet the Objectives Species Crown position Form Health and vigor

49 Concentrate the Growth on Trees That Meet the Objectives

50 Thinning increases diameter growth How? 25 years 25 years

51 Which trees would you remove in a thinning? Why?

52 IMPROVEMENT CUTS (Not final harvest- improve stand) Thinning to Release Sanitation Salvage

53 Not All Trees Are Created Equal

54 HARVEST CUTS (Mature Trees) Even-aged Uneven-aged

55 Light Drives the System Trees compete for light water and nutrients Adding light will stimulate growth New growth can be desirable or undesirable

56 Regeneration What s on the ground? Desirable Undesirable invasive Impact from deer

57 Types of Regeneration Seedlings Natural Planted Stump sprouts Suckers or root sprouts

58 Harvests add light Before adding more light to a stand assess what will happen on the ground The time to treat undesirable vegetation is before adding light

59 To be Sustainable, the average stand diameter after cutting in Intermediate treatments and in Un-even age management should be the same or larger than it was before the harvest

60 N U M B E R O F Single Species Thinning Diameter Before Cutting Diameter After Cutting T R E E S DIAMETER

61 N U M B E R All Species Mixed Species Thinning Sugar Maple O F T R E E S DIAMETER White Ash Black Cherry

62 N U M B E R All Species 12 Inch Diameter Cut O F T R E E S Sugar Maple White Ash Black Cherry DIAMETER

63 sooner or later the cost of past maltreatment must be paid whether as an outlay for silvicultural improvement or as sacrifice of productivity for many more years while nature does the improvement. (Roach and Gingrich 1968)

64 Even-Aged Management Same age not size Clearcut Shelterwood Seed Tree

65 Clearcut: now and after 10 years

66 Seed Tree Harvest A few selected trees (8-10 per acre) are left on site to provide a continued seed fall for additional reproduction; then trees are removed.

67 SEED TREE 8 trees/acre left for seed production Cheap $ Leave for 3 years Less E & S

68 Shelterwood Harvest Shelterwood trees are left on site to provide a continued seed fall and environmental protection for seedlings. Residual trees ( Overwood ) are removed when seedlings are established.

69 Uneven-Aged Management Varying age & size Group Selection Single Tree Selection

70 Group selection harvest

71 Regeneration after 6 years

72 What about Tree Planting? Installing Tree Shelters Deer Fencing

73 Forest Harvesting

74 Logging in Large-Lot Suburban Developments with a Good Forester

75 Use smaller and lower impact harvesting and processing equipment

76 Your woodlot is in fact, a historical document which faithfully records your personal philosophy. Let it tell a story of tolerance toward living things, and of skill in the greatest arts: how to use the earth without making it ugly. Aldo Leopold A Fierce Green Fire

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