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This presentation discusses the use of the Wildlife Tree Extensive Evaluation Checklist for assessing stand-level biodiversity in harvested areas affected by the mountain pine beetle. The checklist was modified for use in evaluating Weyerhaeuser's Timberlands and includes topics such as actual location consistency, windthrow estimates, tree removal percentages, habitat features, stem distribution, and pre- and post-harvest species composition.
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Stand Level Biodiversity • Extensive Evaluation Checklist • January 27th presentation • Field observations • By Bryce Bancroft RPBio
WILDLIFE TREE Extensive Evaluation Present or not? Y N Actual location and size consistent with map? Y N Windthrow estimates (% stems) __________% % trees removed from WTP __________% Comment Metres to nearest mature forest ___________ Habitat, resource or ecological features that anchor patch_________________________ %Stems by WLT class 1 2 3 4 5 6 7 8 9 % by species pre-harvest ________ % by species post-harvest _____________ Harvest –related damage to residual trees ____________% Reserve contains dominant trees Y N Ecological value of reserve L M H Ecological value of retention on block as a whole L M H
The checklist was simplified from the Wildlife Tree Extensive Evaluation Checklist. It was modified for use in assessing stand level biodiversity in areas harvested to manage MPB. This forms part of a Forest Practices Board Special Project. I will be discussing data collection and use from a field perspective including examples from assessing Weyerhaeuser’s Timberlands.
WILDLIFE TREE EXTENSIVE EVALUATION WTP Present or not? Y N Actual location and size consistent with map? Y N What did we learn? WTPs are often not mapped for Beetle Reg blocks and are not an objective for Snip and Skid operations – therefore the yes or no question may be a good one for summarizing results. Actual location and size consistent with map? This is not been found to be an issue, as loggers do generally follow their plans – it is a relatively easy question to answer however if you are looking for general rather than exact location. Another question that is useful for summary wrap ups is the size of the WTP in ha.
WILDLIFE TREE EXTENSIVE EVALUATION Summary of sizes The following graph is a depiction of all retention groups over a four year period within Weyerhaeuser’s Coastal Timberlands, this in conjunction with the total area in retention and total number of groups can provide a framework to help interpret additional research.
WILDLIFE TREE EXTENSIVE EVALUATION • Windthrow estimates (% stems) __________% • What did we learn? • While this is an important question it is a relatively tricky one to answer for a number of reasons. • Timing of the assessment – year one, two, three? After a winter or not … Timing will affect what is found and needs to be accounted for if the data are to be effectively analyzed. • Two measures were identified on the original short form, % of group and % of stems – both have limitations to estimate and what are they telling us of the remaining stand - % of group is hard to estimate, and #of stems can be misleading if they are all small and form a small proportion of the BA. • Using %BA windthrown is another option.
WILDLIFE TREE EXTENSIVE EVALUATION % trees removed from WTP __________% Comment What did we learn? Most of the time this is not an issue – therefore is easy to collect and summarize. By having a comment section, one can provide reasons if any the trees were removed (e.g., danger trees). Where trees have been removed it is often a small proportion of the total and requires some form of tally or plot (s). We have used prism plots to provide an estimate of the BA removed – this again takes into account stem size, rather than just numbers of stems. One must remember to extrapolate the plot for the hole group – thus some judgement is needed.
WILDLIFE TREE EXTENSIVE EVALUATION Metres to nearest mature forest ___________ What did we learn? Most of the WTPs we observed are within the nearest mature forest, so the answer is 0 meters. A question is what size of mature forest patch are we talking about? Is a 1 ha group the starting point? 2 ha, 5, 10, 100? Or are we talking about distance to the next retained group?
WILDLIFE TREE EXTENSIVE EVALUATION Habitat, resource or ecological features that anchor the patch______________ What did we learn? That this is a useful means to inventory the range of features that are left within the WTPs and possibly were used to anchor the patch. Use the checklist - The Extensive Evaluation Checklist provides a list of features that can be checked off. This is useful. I think it is also useful to list attributes of the patch as well as the obvious anchor, if they are present.
WILDLIFE TREE EXTENSIVE EVALUATION %Stems by WLT class 1 2 3 4 5 6 7 8 9 What did we learn? Most of the trees will be WL class one. To get a handle on the % by class, prism sweeps along with observations within the group are recommended. This is a subjective number but can provide a snapshot of what classes are being retained.
WILDLIFE TREE EXTENSIVE EVALUATION % by species pre-harvest ________% by species post-harvest _____________ What did we learn? I am not sure how the preharvest part works at the field level, as it is very difficult to get a preharvest picture without looking at a full range of stumps. The second part - % species post harvest is relatively straightforward and could be assessed against preharvest data, e.g., cruise data, to determine what if any obvious differences are occurring. A Weyerhaeuser example of post harvest data follows. Timberlands Average species composition of all groups. North Island Hw 43% / Cw 26% / Ba 16% /Fd 14% / Dr 1% West Island Fd 54% / Hw 17% / Cw 17% / Ba 7% / Dr 3% / Mb 1% / Pl 1% QCI Cw 56% / Hw 30%/ Yc 12% / Ss 2% South Island Fd 44% / Cw 24% / Hw 11% / Dr 12% / Arbutus 1% / Mb 2% (Bg 1% / Pw 1% / Pl 3%) Stillwater Fd 47% / Hw 26% / Cw 20% / Ba 1% / Yc 3%
WILDLIFE TREE EXTENSIVE EVALUATION Harvest –related damage to residual trees ___________% What did we learn? Damage will be limited to the edge of most groups and for the most part will be minimal. Except along narrow trails where it can be significant – if the matrix is being left. % of the total remaining stems is still often low – may wish to summarize by % of edge stems.
WILDLIFE TREE EXTENSIVE EVALUATION Reserve contains dominant trees Y N What did we learn? To answer this question one needs to know what constitutes a dominant tree, and in the case of Pl – where most are codoms – is it also relevant to add them to the list? Is one dominant tree in the WTP enough to say Yes? How will this information be used?
WILDLIFE TREE EXTENSIVE EVALUATION Ecological value of reserve L M H Ecological value of retention on block as a whole L M H This is a subjective rating that is aided by the Ecological value rating of reserves and Wildlife Tree Value ratings – e.g., below The value of retention on the block as a whole is added to take into account other retention that has not been designated as a WTP. A high-value wildlife tree has at least two characteristics listed below: ·Internal decay (heart or natural/excavated cavities present) ·Crevices present (loose bark or cracks suitable for bats) ·Large brooms present ·Active or recent wildlife use ·Current insect infestation ·Tree structure suitable for wildlife use (e.g., large nest, hunting perch, bear den, etc.) ·Largest trees on site (height and/or diameter) and/or veterans ·Locally important wildlife tree species
WILDLIFE TREE EXTENSIVE EVALUATION Ecological value of reserve L M H Ecological value of retention on block as a whole L M H What did we learn? That some type of value rating is needed to provide consistency. For example the rating by Zone provided in the Extensive Evaluation is useful, E.g., BEC ZONE HIGH MEDIUM LOW IDF Large Fd, dead Some Fd Little structure and decaying trees presence of At
WILDLIFE TREE EXTENSIVE EVALUATION What did we learn? Do your homework up front and no matter how much you do, you may need to improvise once in the field. Thanks PS – we had the key for the gate…