Forest Inventory and Harvest Unit LayoutBy Grant Becker

IntroductionForest inventory is of most importance when it comes to forest

management. Whether or not the forest is being managed for fish and wildlife, carbon sequestration, water purification or timber, projected growth rates can reveal a great deal about forest health. Conducting a full inventory can lead to assumptions about past, present and future conditions relating to competition and suppression and disease and insect infestation to name a few. Economically it is vital to conduct an accurate survey to establish initial and future volumes and to recognize which species is the best fit for regeneration if the site is healthy enough to supply future cohorts. Forest mensuration plays a vital role in monitoring forests and can reveal many other issues which can provide starting points for silvicultural prescriptions and management plans. Overall it will greatly aid in further understanding forest productivity and help guide the decision making processes that govern the sustainability and health of the forest.

Harvest unit layout is a key step after the inventory is accounted for. This step sets up the entire harvest, from boundary placement and property marking to water typing and road construction, this step is critical. Based on this your economic return may vary depending on the severity of slope, landscape, water bodies, and more. These factors can bring a harvest operation to a standstill, but if properly assessed the area can be efficiently logged while providing income and a future area for regeneration.

The permitting process is the last step before harvest. This step lets the Department of Natural Resources know your intent. From acreage to stream typing to slope variability this covers just about all the landscape features that may create problems and excess damage during the harvest operation. Overall, this holds the property owner accountable for any forest operations that occur on their property in regards to silvicultural prescriptions.

ObjectivesThe purpose of this project is to perform a forest inventory and to

develop a harvest unit layout based on stand area and projected yield. There are many different techniques used to obtain data about forest composition. Some of these include aerial photographs, satellite imagery, remote sensing and radar. Overall, the goal is to implement skills learned in the classroom out in the field and to run statistical analysis on the data recorded. Along with this there will be many skills learned out in the field that will be brought back to the classroom for further study. • Forest Inventory• Harvest Unit Layout• Forest Practices Application

MethodsSite Description: The stand evaluated is located in the Hamilton Tree Farm, in Skagit County, Washington. The tree farm is 147,000 acres and owned by Sierra Pacific Industries. Areas of higher elevation are typically composed of Western Hemlock and true firs, while the lowlands are dominated by Douglas-fir. Overall, there is a 60/40 composition of DF to Hem. The study site is a 16 acre, 48 year old stand composed of primarily Douglas-fir and Red Alder. This project used direct measurement methods employed in the field along with aerial photographs and previous/historical data for the particular stand to obtain data.

Results

Discussion

Mensuration: Summarize inventory data into estimates of volume by species, total forest volume, standard error, derive confidence intervals, and to produce stand and stock tables by conducting variable area plot surveys. Additional stand features were noted and added to the map during the harvest layout. Equipment used included a hand compass, aerial map, jake staff, and 75 foot diameter/distance tape, calculator, flagging, and a Spiegel Relaskop.

Harvest Unit Layout: This process focused on ribboning the boundary of the stand. All significant environmental features were noted, ribboned and later added to the map to include windthrow, storm damage, streams, and breaks in slope, forest gaps, and disease pockets. Streams were to be classified using water typing guidelines provided by the Department of Natural Resources. All water types were to be marked up to 200 feet of the boundary. Under DNR guidelines, there must be five trees per acre left over. Two of these must be green recruitment trees, three must be wildlife reserve trees, and there must also be two downed logs left. In order to meet the wildlife reserve tree retention requirements, wildlife trees must be at least ten feet in height and possess a DBH greater than twelve inches. These trees were ribboned off in clumps depending on the landscape features. Another requirement is that no point within the harvest can be more than 800 feet from a wildlife reserve tree or green recruitment tree retention area. This gives a maximum distance of 1600 foot gaps that can be created on the site. Other steps for harvest unit layout can include locating log decks, landings, roads, stream crossings, skidding and yarding paths, bridge/culvert locations, and assessing logging road grade lines. There are many other requirements and regulations made by the DNR, these are just a few.

Forest Practices Application: After the layout was completed, the rest of the day was spent in the office going over the permitting process and creating a map with all noted significant land features and forest stand attributes. This also contained the locations of the leave trees, boundary/property lines and landings. Arcmap Gis is the mapping software used to add all required attributes, boundaries and layers. A Western Washington Forest Practices Application was completed provided by the Department of Natural Resources.

AcknowledgementsI would like to thank my advisor, Dr. Eric Turnblom for guiding me through the capstone process. I would also like to thank Sierra Pacific Industries for providing me access to their company lands. Finally, I would like to thank Daisuke Sakuma, the Hamilton District Forester who guided me along each step of the project.

Stand Table

Stock Table

InventoryPlot

Tree Species DBH DistanceBottom

% Top % Height LCR %Snag

Height BA CVTS Tarif CV4 CV6 SV6 SV632

1 1 BLM 45 66 -5 85 90 30 11.0 342.1 27.6 331.0 328.7 1878.6 1461.1

1 2 WH 11 66 -12 95 53 80 0.7 14.2 21.3 13.4 12.1 46.7 31.7

1 3 BLM 15 66 -4 75 79 30 1.2 37.2 28.6 35.7 35.0 168.2 128.2

1 4 BLM 18 66 -4 83 87 30 1.8 58.5 30.6 56.4 55.8 289.0 225.4

1 5 WRC 27 66 -3 83 86 90 4.0 113.0 25.6 109.2 108.4 575.9 426.8

2 1 RA 8 50 -24 140 82 40 0.3 13.1 39.7 11.4 7.0 26.5 22.0

2 2 BLM 16 66 -11 77 88 60 1.4 47.5 31.8 45.6 44.9 227.6 179.2

2 3 BLM 16 66 -11 95 106 60 1.4 58.5 39.2 56.2 55.3 297.4 246.3

2 4 BLM 17 66 -11 76 89 60 1.6 53.9 31.8 51.9 51.3 264.3 208.2

3 1 DF 18 66 -4 105 109 60 1.8 68.4 35.8 65.9 65.2 353.9 287.5

3 2 DF 20 66 -3 105 108 80 2.2 81.3 34.2 78.4 77.8 427.9 344.1

3 3 DF 22 66 -7 107 114 80 2.6 102.0 35.2 98.5 97.8 554.8 450.2

3 4 WRC 11 66 -7 48 55 90 0.7 15.1 22.5 14.1 12.8 50.3 35.0

3 5 WRC 12 66 -7 41 48 90 0.8 15.2 18.8 14.4 13.5 52.0 33.0

3 6 WRC 15 66 -8 42 50 90 1.2 23.3 17.9 22.3 21.9 89.6 55.3

3 7 DF 21 66 -8 106 114 50 2.4 94.1 35.8 90.8 90.1 508.3 413.6

3 8 DF 20 66 -8 110 118 50 2.2 89.8 37.8 86.7 86.0 487.2 401.3

3 9 DF 31 66 -2 125 127 50 5.2 209.3 35.8 202.4 201.0 1220.8 1002.6

4 1 RA 9 66 -3 55 58 30 0.4 11.3 26.3 10.2 7.7 28.7 21.3

4 2 RA 10 66 -3 66 69 25 0.5 16.7 30.8 15.4 13.1 54.1 42.1

4 3 RA 11 66 0 80 80 25 0.7 23.5 35.2 22.1 19.9 89.7 72.3

4 4 RA 8 66 -3 65 68 20 0.3 10.7 32.5 9.3 5.7 20.6 16.3

4 5 RA 14 66 -1 107 108 30 1.1 51.6 45.9 49.4 47.9 255.5 218.0

4 6 RA 13 66 -1 105 106 30 0.9 43.8 45.7 41.8 40.0 207.1 176.5

4 7 RA 11 66 -3 64 67 70 0.7 19.4 29.1 18.2 16.5 70.3 53.7

4 8 RA 11 66 -2 85 87 70 0.7 25.7 38.5 24.1 21.8 100.5 82.7

4 9 RA 10 66 -4 54 58 68 0.5 13.9 25.5 12.8 10.8 42.5 31.1

5 1 DF 20 66 -1 113 114 40 2.2 86.4 36.3 83.4 82.7 463.3 378.2

5 2 DF 22 66 -1 128 129 40 2.6 117.3 40.5 113.3 112.5 664.5 556.3

5 3 DF 23 66 -7 120 127 40 2.9 124.5 39.2 120.3 119.4 706.4 587.9

5 4 DF 23 66 2 135 133 40 2.9 131.2 41.4 126.8 125.8 755.2 635.3

5 5 DF 19 66 0 120 120 50 2.0 83.8 39.2 80.8 80.1 452.2 375.1

5 6 DF 13 66 0 105 105 38 0.9 37.2 38.8 35.5 34.0 169.1 139.5

6 1 DF 12 66 -7 79 86 45 0.8 25.8 32.0 24.5 22.9 104.6 82.3

6 2 DF 17 66 0 105 105 42 1.6 59.3 35.0 57.1 56.4 299.4 241.8

6 3 DF 25 66 -12 110 122 85 3.4 137.6 36.5 132.9 132.0 777.8 638.1

6 4 DF 11 66 -5 75 80 0 80 0.7 20.4 30.6 19.2 17.3 75.0 58.2

7 1 DF 19 66 -5 122 127 30 2.0 89.3 41.8 86.1 85.4 490.5 412.3

7 2 DF 12 66 2 105 103 38 0.8 31.7 39.2 30.0 28.1 135.6 112.1

7 3 BLM 12 66 -5 68 73 60 0.8 22.4 27.7 21.2 19.9 86.9 65.5

7 4 RA 16 66 -3 105 108 45 1.4 66.7 44.7 64.1 63.1 350.3 297.8

7 5 DF 18 66 -2 112 114 40 1.8 71.9 37.7 69.3 68.6 377.8 310.6

8 1 BLM 9 66 -2 68 70 34 0.4 12.4 28.9 11.2 8.5 32.4 24.7

8 2 DF 18 66 -3 100 103 29 1.8 64.1 33.6 61.8 61.2 325.7 260.5

8 3 DF 18 66 2 106 108 0 108 1.8 67.7 35.4 65.2 64.5 349.2 283.0

8 4 RA 13 66 0 93 93 60 0.9 38.1 39.7 36.3 34.8 174.2 144.5

9 1 DF 31 66 -13 130 143 60 5.2 239.5 41.0 231.6 229.9 1454.4 1229.9

9 2 DF 24 66 -16 120 136 58 3.1 144.9 41.8 140.0 139.0 844.7 712.7

9 3 DF 32 66 0 145 145 60 5.6 257.1 41.3 248.6 246.9 1571.6 1332.0

9 4 DF 11 33 -21 135 78 57 0.7 19.9 29.7 18.6 16.8 72.3 55.6

9 5 DF 16 66 -4 95 99 45 1.4 49.9 33.5 48.0 47.3 243.1 194.1

9 6 DF 14 66 8 115 107 40 1.1 43.2 38.5 41.4 40.2 205.3 169.2

DBH DF BLM RA WRC HEM TOTAL TPA

8 11.1 44.4 55.5

10 12.7 44.4 6.3 6.3 69.7

12 16.7 5.6 9.9 5.6 37.8

14 4 3.7 4 3.7 15.4

16 5.9 9.5 3.2 18.6

18 14.8 2.5 17.3

20 8.1 8.1

22 6.8 6.8

24 2.9 2.9

26 1.1 1.1

28

30 1.7 1.7

32 0.8 0.8

34

36

38

40

42

44 0.4 0.4

46

48

50

TOTAL TPA 74.4 32.8 105.9 16.7 6.3 236.1

DBH DF BLM RA WRC HEM TOTAL SV632/ACRE

8 248.4 700.1 948.5

10 766.7 2002.2 236 213.3 3218.2

12 1773.3 370.7 1547.6 186.7 3878.3

14 703.6 464.4 906.7 200.4 2275.1

16 1299.6 1941.3 948 4188.9

18 4648 567.1 5215.1

20 3052.9 3052.9

22 3578.7 3578.7

24

26 477.3 477.3

28

30 1893.3 1893.3

32 1060 1060

34

36

38

40

42

44 588 588

TOTAL SV632/ACRE 18776.1 4179.9 6104.6 1100.4 213.3 30374.3

Net SV632/ACRE 29270.74

80% CI: 805.4± 𝟏. 𝟑𝟗𝟔𝟖 𝟗𝟕. 𝟒 ≫ 𝟔𝟔𝟗. 𝟑𝟓, 𝟗𝟒𝟏. 𝟒𝟓 × 𝟒𝟎 ≫ 𝟐𝟔𝟕𝟕𝟒, 𝟑𝟕𝟔𝟓𝟖

Advisor: Dr. Eric Turnblom

The project went as planned. There were new techniques discovered dealing with relaskop use that sped up the measuring process. The layout process was insightful and fairly straight forward. The LiDAR map was helpful when placing leave trees and potential roads. The area was fairly flat with no streams present, so many of the usual steps were skipped, such as stream typing and slope stability. Since the area rarely exceeded grades of 30% shovel logging will be used for the logging operation.

Minimizing the effects of timber harvest is an important aspect of the unit layout process. There are ways to limit the apparent size of the harvest using natural terrain already in place. Shaping clearcuts to look like natural terrain can boost the aesthetics of the operation. Road layout can greatly increase this by creating narrow roadways into to harvest area to limit the view from public roads. Multiple stage cutting can greatly reduce this as well and can change public perception. Having small patches can greatly enhance aesthetics as compared to large clearcuts.

Besides the aesthetics, there are other important areas to focus on. Riparian management zones are very important and provide ecosystem services, such as water filtration and habitat for many species of fish and wildlife. To reduce this it is important to harvest during certain times of the year. In the winter months these areas generally have increased flow and surrounding soils become much more saturated. Increased buffers are generally used and can reduce the input of sediment, chemical, nutrient, and debris flow into streams, lakes and wetlands. Reducing damage to the soil can maintain good root penetration, porosity, and aeration which will maintain healthy areas when it comes time for regeneration. There should be minimal change to the hydrologic cycle, and this can be accomplished by installing culverts, bridges, or simply by avoiding these areas if possible. However, culvert installation can create point sources of pollution and should be evaluated by an engineer before operations commence. The type of equipment used can also reduce these risks. Skyline operations reduce the impacts to the soil in terms of compaction and disturbance to saturated soils but are higher in cost and are typically used on steep terrain. Shovel logging and other ground based operations will increase these effects but are cheaper and commonly used on flat ground. Shovel logging has benefits as rubber tired skidders aren’t used. Tracks are used which increase the surface area and decrease direct weight and compaction, and logs aren’t dragged across the landscape.