Forest Investment Account LBIP : Edge and Experimental plots in TFL 39 and TFL 44.

Transcription

1 Smith, FIA LBIP : Project Report 1 Forest Investment Account LBIP : Edge and Experimental plots in and TFL 44. Nick Smith, Nick Smith Forest Consulting for: Bill Beese, Western Forest Products Inc. This report covers FIA LBIP a continuation of FIA LBIP ( ), ( ) and ( ) which covers measurement of two type of data: 1 Edge Transects: for establishment, maintenance and remeasurement from among ten sites. See Table 1. (also Appendix 1, 2 and 3 for more information). 2 Experimental Transects: for establishment, maintenance and remeasurement from among nine sites. See Table 2 (also Appendix 1, 2 and 3 for more information). Project Deliverables Planned (from original proposal): The deliverables from the project are a sound set of investigative and experimental plots producing valuable and unique data. Data analysis and modelling are funded separately via FSP projects Y and Y The focus of this project is the establishment and measurement of the edge and experimental plots. Note: data measurement costs vary from year to year (for instance new windthrow and weather conditions slows down work considerably); it is not possible to precisely estimate measurement costs. Specifically plans are to use the following priorities: 1. Edge sites (Table 1): no work. 2. Experimental sites (Table 2): priority on measurements at: TM188 measure planted, natural and retained, OP0185 maintain seedling protectors (vexar) and GI100 maintain vexar then ST42. Database work includes: preparation of handheld programs, data retrieval and storage, data manipulation and assistance with report writing. Report writing includes charts/tables of data collected. A report will summarize the data collected at each site. This information will contribute to Western Forest Products data and information that will assist in potential analyses, modelling and presentations at upcoming conferences and workshops. Work Planned for (from original proposal): Table 1 and Table 2 show field tasks to be completed. Maintenance (where no measurements are taken) includes moving tags up on trees; ensuring vexar/cages are

2 Smith, FIA LBIP : Project Report 2 maintaining protection, reestablishment of stakes and installation of aluminum stakes. Measurement includes actual field recording of seedling dimensions and may also include general plot maintenance. As a minimum planted trees, natural seedlings and retained trees will be measured at each site. We will remove elk protection cages at TM188 on all trees >1.5m, planted, natural and retained trees will be measured in that order as funds are available. At Op0185 plastic cages (vexar) will be replaced to prevent Elk browse (it is a heavy Elk use area). At GI100 vexar will be removed from trees as trees are tall enough to withstand any deer browsing, the area is in a deep snow pack area and funds are not available for yearly maintenance. ST45 remeasurement will be undertaken if funds remain after completion of above projects remains, priority order at ST45: planted, retained, natural regeneration. Work Accomplished For background refer to Appendix 1 and 2. For maps of areas refer to Appendix 3. Overview All work was accomplished at GI1000, OP0185 and TM188 as planned. However, ST42 measurements were not undertaken as funds were insufficient. Note that FIA funded a portion of the cost of completely remeasuring and maintaining plots and sites described below. OP0185 Old disintegrating 4 vexar (deer protectors) and snow deformed support rods were replaced by special order 5 vexar and support rods on approximately 2000 planted Douglas-fir trees. The area is heavily used by Elk so that installing new vexar was crucial for planted seedling survival. The vexar are 36 tall and can be moved up to four feet. Old rods and vexar were piled at road side in plastic bags and a portion were taken to town for later disposal/recycling. The remaining bags will be transported out at a later date. Saltspring Planters provided the vexar and metal rods. For more information and to confirm work done contact Bill Beese ( ) or Gary Patrucco ( ). GI100 Vexar and support rods were removed on approximately 1400 planted trees. The vexar were not replaced as deer browsing has been minimal at the site and yearly snowfall had necessitated yearly visits to maintain. (Access demands the use of a boat). Contact Rudi van Zwaiij ( ) for more information and to confirm work done. TM188 Appendix 3 Fig. 2 shows a map of the site and the location of the sector plots. TM188 is a gross area ha block partitioned into 5 approximately equal areas and randomly assigned one of five treatments: a 5%, a 10% and a 30% dispersed retention by basal area, a clearcut and a leave area. This study area was part of a larger scale Adaptive

3 Retention Smith, FIA LBIP : Project Report 3 Management and Monitoring (AMM) set of experiments designed to examine a range of variable retention leave amounts and patterns in large operational size blocks. (See Appendix 3, Fig. 2). Table 1 shows starting conditions. Table 1. TM188 stand statistics. basal area goal BA m 2 ha -1 start (% leave basal area) distance between groups, m trees per group Stems, ha -1 Average diam (Dq), cm Area, ha. 5% 2.4 (5%) % 5.1 (10%) % 14.0 (29%) Planted, natural regeneration, retained trees and unharvested control plots were remeasured. Elk cages (made from wire) were removed from all trees >1.5m. Aluminum tags on cable ties were moved up and replaced where needed. Stakes were reflagged and new GPS coordinates taken at key locations in each plot. A field audit was undertaken. There were approximately 2400 planted trees remeasured in 26 sector-plots. 15% of the trees were western red-cedar. TM188 8 years after planting TM188 8 years after planting Basal diameter, mm Species Height, cm Species 0 Clearcut 5% 10% Treatment 30% Cw Fd 0 Clearcut 5% 10% Treatment 30% Cw Fd Fig. 1. TM188 Douglas-fir and western red cedar planted trees eight years after planting. One standard error bar is shown. A covariance analysis using a General Linear Model (GLM) with plot site index as the covariate (gathered prior to logging) was undertaken. For Douglas-fir basal diameter, the

4 Smith, FIA LBIP : Project Report 4 30% dispersed treatment was significantly lower (p<0.05) than the clearcut and 5% retention but not the 10% retention. For Douglas-fir height there were no significant differences (p<0.05) between treatments. For western red cedar, basal diameter was significantly lower (p<0.05) in the 30% treatment compared to the other treatments (including the clearcut); in addition the 10% retention was significantly lower than the clearcut (p<0.05). TM188 8 years after planting year mortality rate Species 0.0 Clearcut 5% 10% Treatment 30% Cw Fd Fig. 2. TM188 mortality rates after 8 years. One standard error bar is shown. There were generally no significant differences (p<0.05 GLM using site index as a covariate) between mortality rates except for Douglas-fir between 10% and the clearcut. Generally microsite effects appear to override treatment impacts on mortality. TM188 Retained trees TM188 Retained trees basal area, m 2 /ha % 10% 30% AREA DATE stems per ha % 10% 30% AREA Fig. 3. T188 live standing retained tree statistics in 2002 and in 2009.(No error bars as there was a complete tree enumeration on the approximately 1600 dispersed trees) DATE

5 Smith, FIA LBIP : Project Report 5 Fig. 3 shows the impact of windthrow on retained trees eight years after planting. Approximately 60% of trees and basal area remained standing at 5% and 10% retention while approximately 85% of trees and basal area remained standing at the 30% retention treatment. TM188 natural regeneration TM188 natural regeneration height, cm 200 stems per ha % 10% 30% CC AREA species CW FD HW % 10% 30% CC AREA species CW FD HW Fig. 4. Natural regeneration over 50cm tall eight years after planting. Caution numbers are draft only. Fig. 4 shows natural regeneration from a series of 2.4m radius plots spaced 10m along the spine of each sector plot. There was no pattern with treatment except that there was less Douglas-fir natural regeneration in the clearcut compared to the other treatments. There was considerable western hemlock regeneration in the 30% and 10%. Douglas-fir natural regeneration was taller than hemlock or cedar. Note that natural regeneration analyses are preliminary awaiting further checks. In addition the unharvested control plot data have not been analysed yet. Audits A field audit was carried out on all phases of TM188 data collection. See the separate spreadsheet attachment. Generally the measurements were of high quality. In 2008 a large area of Stillwater suffered a vole outbreak in early spring when there was a heavy snowpack. The voles resorted to snipping off and eating terminal Douglas-fir buds. As this was a novel event the field crew did not record consistently and there was no pathological code. After audit the field crew re-checked all plots not audited and the revised data was entered into the data base. Audit results were presented and discussed with the field crew. Database The field data was checked and updated and entered into a central Access database. Programming to internally improve the checking and summary of the data and in preparation for further analysis was undertaken.

6 Smith, FIA LBIP : Project Report 6 Conclusions Valuable maintenance work was completed at OP0185 (where old vexar was replaced) and GI100 (where vexar was removed). Considerable data was collected at TM188 and initial analyses commenced. These data confirm previous findings that most impacts of retention are at the higher dispersed tree levels (30%) and indistinguishable from between site variability at lower dispersed tree levels. The next measurement is scheduled for 10 years post planting and then every 5 years.

7 Smith, FIA LBIP : Project Report 7 Table 1. Edge Study Site Description Opening Name Division/ Operation #Transect s Bearing Estab Species Fisheye/ moisture work to be done starting fall 2007 Newstead N370-1 West Island TFL 44 4 N,S,E,W 1999 Hw No work planned Newstead N300-5 West Island TFL 44 1 N 1999 Cw No work planned Stove Creek AV Mid Island, TFL39 12 N,S,E,W 1999 Fd No work planned 5521 Port McNeill 4 N,S,E,W 1999 Ss,Ba,Hw,Cw No work planned 5409 (MC22) Port McNeill 4 N,S,E,W 1999 Ss,Ba,Hw,Cw 10 year remeasurement planted trees Estimated crew days:3 347 North Island 16 N,S,E,W 1999 Hw No work planned

8 Smith, FIA LBIP : Project Report 8 ST China Creek Stillwater (now Island Timberlands ) TFL 44 (now Island Timberlands ) 4 N and S 1999 Fd,Cw Planted, natural and retained trees Estimated crew days: 3 4 N,S,E,W 2000 Fd No work planned Br 90 Sproat TFL 44 4 N,S,E,W 2000 Fd No work planned Branch 112A OP 4524 Sproat TFL N,S,E,W 2001 Fd Fisheye and moisture No work planned

9 Smith, FIA LBIP : Project Report 9 Table 2. Experimental Study Sites Name Area Planted Species Remeasurement interval in 2009 Type %Retention Fisheye/ moisture Work to be done (estimated number of 2 person crew days). TM188 Stillwater Mar 2002 (caged Mar 2003) Fir 80%., cedar 10% 8 (fall) Dispersed 5,10,30,100,0 Moisture (1) (fish eye done) Measurement planted, natural and retained Estimated crew days:15 TM128 Stillwater Mar 2002 (caged Mar 2003) Fir 8 (fall) Dispersed 5,15,0 Moisture (1) (fish eye done) No work planned OP38250 North Island TFL 39 Aug 2002 (cedar vexared Aug 2002) Hemlock 80%, cedar 20% 7 (fall) Group retention 10,20,30,0, 100 Moisture (1) (fish eye done) No work planned OP5599 Port McNeill April 2006 Hemlock 4(fall) Group Size Large, small, medium,0,100 No work planned GI100/GI100b Stillwater Oct 2005 (to be vexared) Fir 4(fall ) Needs maintenance of vexar Group Retention 10,20,30,0, 100 Fisheye/ moisture (3) Remove vexar before sow-fall Estimated crew days: 3

10 Smith, FIA LBIP : Project Report 10 OP0185 North Island TFL 39 Aug 2005 (vexared Oct 2005) Fir 4(fall) Needs maintenance and replacement of vexar Group Removal 0,100, <1ha patches in 4 sizes (0.1-1ha) Maintain vexar: replace, repair and move up on tree to avoid elk browse. Estimated crew days:15 OP HD216 Queen Charlottes May 2006 Hemlock 4(fall) Group Size Large, small, medium,0,100 No work planned LL55 Stillwater Mar 2002 Fir cedar 8 (fall) Dispersed 5,15,0 Moisture (1) (fish eye done) No work planned OP Franklin TFL 44 (Klanawa) March 2006 Hemlock cedar 4 (fall) Needs maintenance 7 transects destroyed by pile burn Group Size Large, small, medium,0,100 Fish eye/ moisture (3) No work planned

11 Smith, FIA LBIP : Project Report 11 Appendix 1 Objectives Need for study: purpose, significance and existing standards Increased retention trees in openings, such as wildlife tree patches or variable retention, leads to increased edges compared to clearcuts. This study is designed to set up field studies and collect data that examines the effects of forest edge on the growth of the regenerating crop, planted and natural. As this is a novel issue there are no published Provincial standard methodologies or standard approaches. Design: rationale. There are two types of field studies: 1) Edge: the establishment of planted transects at intact stand boundaries and retention patches along N,S,E and W directions, 50m into the harvested area and at least 5m into the retained areas. This part of the project is investigative; designed to generate hypotheses and examine underlying sources of variability. 2) Experimental: detecting the response of trees at edges and under dispersed retention for larger populations with statistically valid controls and treatments. This part of the project is concerned with hypothesis testing of larger populations of trees. Methods: 1) Edge: A series of flat to gentle sloping sites (slope <5%) were selected comprising, generally, edges and retention patches. The intent was to try to find conditions under which an edge effect response could be forced. At each site N, S, E and W aligned transects of planted trees were established. At least 3 rows of planted trees extending from ~ 5m inside the stand boundary to approximately 2 tree lengths are established. Species included western hemlock, amabilis fir, western red cedar, Douglas-fir and Sitka spruce. Trees are measured for caliper and height at time of planting and protected with vexar or wire cages where deer/elk were a problem. Distance from stand edge was recorded to each tree. Prism plots are established at the stand boundary ( ½ plot or 180 o sweep with the prism swung from the transect stand edge) to collect leave tree data: height, height to live crown, diameter, height to break, decay code if dead or damaged. In addition regeneration plots are established at -5, 0, 5, 15, 30 and 50m from the stand edge and all natural regeneration tagged and recorded. Measurements for the retained trees (prism plots), planted and natural regeneration plots are planned for: time of planting, 1, 3, 5, 8, 10 years after planting and then every 5 years. (Note measurements dates are +/1 year due to fluctuations in funding). Table 1 lists the existing plots in and 44. 2) Experimental. Appendix 2 details the design of the experimental sites: there are two basic types:

12 Smith, FIA LBIP : Project Report 12 Large scale: comprising five randomly allocated treatments, from among four design, over a large (generally 100 ha) block Supplemental: comprising three randomly allocated treatments, from among two designs, over a smaller (generally 30ha) block. Sector plots (comprising residual and planted) and fixed area plots (comprising natural regeneration) are established at each site. At least 3 sets of sector plots are established per treatment. Plots generally cover 2ha (up to 3ha) and 2500 planted trees (up to 3500) per site. Measurements are made at planting, 1, 3, 5, 8, 10 and then every 5 years thereafter. Note the periods may vary +/- 1 year depending on funding. Fisheye and moisture profile measurements are taken close to time of planting (see Table 1 and 2). Fisheye photography is used to permanently capture canopy coverage and can be used to model the light environment Frazer et al. (1999). Moisture in the forest floor can rapidly be assessed using a portable moisture meter (ftp://ftp.campbellsci.com/pub/outgoing/manuals/hydrosns.pdf). The fisheye and moisture meter measurements are made at the same time from inside the variable retention/edges and out into the harvested areas during summer months (specifically distance from edge: -5m, 0m,5m,15m,30m,50m and every 50m to transect end). At each sample point one fisheye photo is taken but at least 6 moisture readings are made along a 3m perpendicular line at a depth of 12cm. More detailed microclimate data are being collected using separate funding at other sites (the instrumentation is currently at the Port McNeill 5599 site (Table 2)). Data are collected using existing handheld data recording software and programs. Data are stored in an access database format using an existing database structure; data will be edited using standard procedures. Every tree has a location in respect to stand edge or central pivot point. Literature Cited Frazer, G.W., C.D. Canham & P. Sallaway Gap Light Analyzer, Simon Fraser University, BC and the Institute of Ecosystem Studies, NY, Burnaby, BC and Millbrook, NY Iles, K. and N.J. Smith A new type of sample plot, which is particularly useful for sampling small clusters of objects. For Sci. 52(2): Smith, N.J., K. Iles and K. Raynor, Investigation of some sector sampling statistical properties. For. Sci. 54(1):67-76.

13 13 Appendix 2. Experimental and details of sector and regeneration sampling. Larger (100ha, 20ha per treatment) and smaller (60ha, usually 10ha per treatment) experimental sites are described in detail below. Large scale experiments: treatments are allocated at random, each area is approx. 100ha in size (each treatment is 20ha), harvesting and planting are the same throughout. Variable Retention Experimental Sites Group Retention: Variable % of area retained; group sizes range from 0.2 to 0.5 ha Dispersed Retention: Variable basal area retained; single trees or small groups up to 0.1 ha Group Size: All treatments retain 15% of area Large groups ha Medium groups ha Small groups up to 0.1 ha Group Removal: All treatments retain 15% Short cutting cycle every 5 7 years Long cutting cycle every years

14 14 Supplemental experimental sites: treatments are allocated at random, each area is approx ha in size (each treatment is 10ha-20ha), harvesting and planting are the same throughout. The intent is to allow treatments on smaller areas than the main experimental sites: there is no uncut control and only two treatments. The levels chosen are minimums used in WFP Timber Zones (5% dispersed retention and 10% group retention). Supplemental Variable Retention Experimental Sites Dispersed Retention: Variable basal area retained; single trees or small groups up to 0.1 ha Mixed Retention: Group (0.25ha+) and dispersed trees (0.1ha and less) retained Table 2-1. Current on the ground installations for the experimental sites: all sites harvested and planted. Experimental 2 Supplemental 2 Type Old growth Second growth Second growth Group OP38250 GI100 TM128, LL55 Dispersed TM188 None planned Group size OP862222, HD216 OP5599 None planned Group removal OP0185 None planned Mixed None planned None planned Malahat Private land 2 Original plan to establish 3 of each type for Experimental and at least 2 of each type for Supplemental. Note LL55 is 10ha in total size so departs from plan to keep each treatment at 10ha minimum in the Supplemental sites. A system called sector sampling is used on experimental (Iles and Smith, Smith et al. 2009). Sector samples can be located subjectively inside retained groups, however, the sector plots themselves must be oriented at random.

15 15 Reduction to partial sectorreduced effort Harvest area edge Pivot point Constant angle which has variable area Remaining group of trees Schematic representation of sector plot sampling Each tree in the sampled population has an equal chance of being selected proportional to the angle of the sector plot, i.e. a 36 degree sample selects each tree with a 10% probability. Except in the control areas, the sectors are split into four equal rays orientated at right-angles to each other to examine the affect of aspect. Distance from the pivot point and edge is recorded for each tree. Growth per unit area is determined by measuring the area within the sector. All residual stems >1.3m and 4cm dbh are measured in the sector plots: prior to harvest 50% of the sectors are measured at random: after harvest all trees >1.3m and 4cm dbh are measured if remaining following harvest. All planted trees are measured in the sector plots and all natural regeneration or residual trees (<4cm dbh) are measured in separate 2.4m radius plots established at -5, 0, 5, 15, 30, 50m then every 50m and at the end of the sector transect. Data include distance from edge, basal diameter, breast height diameter, total height and pathological data. Note that although all areas per site are planted with the same seed source and stock type it is usually necessary to ensure that the sectors are planted specially. This is because most areas have a mixture of a minor species, such as western red cedar among Douglas fir. Thus the sector plots are laid-out ahead of the planting to make sure the seedlings (usually either Douglas fir or western hemlock) are only planted in the sectors and that planting extends up to two planting rows into edges or retention groups. On some sites it is necessary to vexar or cage trees against deer/elk. See Table 1 and 2 for more specific data.

16 16 Appendix 3. Sector plot layout at OP0185, GI100 and TM188 Fig 1. GI 100, Goat Island, Powell River. Area, showing sector plots. Fig. 2. TM188, Powell River, showing sector plots.

17 Fig. 3. OP0185, Memekay, near Campbell River, showing sector plots. 17