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WSU/Pend Oreille Extension introduced the Sense of Place series in 1999, with a focus on place-based stewardship education. Since 2001, a partnership with the Kalispel Tribe of Indians Natural Resources Department (KNRD) has supported this newsletter and allowed us to expand class offerings through EPA funding. Further staff support comes through Renewable Resources Extension Act (RREA). Many thanks to our partners and to you, our readers, for your continued enthusiasm for "digging" into the natural history and culture of this part of the world.

Managing for Big Birds on a Small Acreage


by John Stuart • Local Birder

One of the major goals of our family's forest stewardship plan is to improve pileated woodpecker habitat on our property. We love the sights and sounds of these birds, but even more, we want to be assured by their “keystone” presence that our woods can support a host of other wildlife as well. We know that dead wood—both vertical and horizontal—is a crucial element. But like much private forestland, the landscape surrounding our property has been logged periodically, and many firewood cutters (like ourselves) have removed all accessible dead wood. There are noticeably fewer large snags and fewer large trees to serve as replacements in our area than when we first moved here 35 years ago. Our forty acres is a small part of the 500 to 1,500 acre territory generally used by a pair of pileated woodpeckers, but if we can provide optimum “core habitat” conditions on our place, it may help keep these birds in the neighborhood.

State forest practice regulations require leaving a few snags and down logs per acre during logging, but those numbers are bare minimums. So what constitutes optimum pileated woodpecker habitat? How many snags and down logs (and what sizes and species) do we want to aim for on our place? I've done some research to determine what these numbers might be for different sites on our mixed conifer forest (see table below.) Our long term goal is to bring 90% of our acreage up to the “better” category, and 5% into “best.” Carrying out this stewardship plan goes beyond my own lifetime, since achieving these optimum conditions will call for growing much larger trees. But if we manage towards this goal and include it in our written plan for future owners to read, perhaps we've increased the long-term odds for these birds and the other species depending on them.

Because of the research of many people in the last 35 years, we know what needs to be done. If it were up to me, the names of Keith Aubry, Catharine Raley, Evelyn Bull, and their many associates would be as well known as any rock stars. Their research over the last few decades tells us what is needed to invigorate pileated woodpecker habitat and bring the population losses to a halt before they become seriously threatened.

So, to the details... pileated woodpeckers do about half of their foraging on down logs serving as horizontal chowlines. In the slow process of decaying into new forest soil, this “large woody debris” is constantly inhabited by countless insects, spiders, rodents, reptiles and larger critters as well. A study in the Blue Mountains of northeast Oregon (very similar to northeast WA) found 179 vertebrate species using these logs at some time in their lives, not to mention all the bugs.

Quality pileated habitat includes big trees, both live and dead, preferably some up to three and four feet in diameter in our area. The bird needs dead trees at least 20” diameter breast height (dbh) for its basic activities of nesting and roosting. I've watched them spewing mouthfuls of chips two or three feet out the hole with a pile building up on the ground while they carry on a conversation of squawks, kuks and little humming sounds. It is common for a pair to build several different new cavities each spring and then after all that work, decide to use just one. The key for these cavity trees is that bigger is always better. And of course, the bigger they are, the longer they last. In our area the best trees for cavities are ponderosa pine, western larch, cottonwood, aspen and grand fir. The ubiquitous Douglas fir and other tree species will harbor food organisms eaten by all snag lovers, but they tend to lack the heart-rot fungi often associated with the first five species. When present, this fungi causes the tree's heartwood to soften, leaving the sapwood as a hard shell on a partially hollow tree. It is important to note that for cavity trees, any live tree with heart rot may serve as well or even bet- 4 ter than snags. These green trees can live very long despite cavity excavations, growing in size and play- ing this role for perhaps hundreds of years. With age, they can become riddled with holes and sometimes are nest trees for several different species in a single year. To boot, they are virtually worthless at the sawmill, so leaving them standing is the best option for everyone.

Retaining cavity trees and logs can be compatible with thinning or logging. Fire-wise advice emphasizes the benefits of burning or chipping smaller flammable material, pruning branches, and removing “ladder” fuels. Snags and large down logs are generally not a fire problem except for the zone immediately around homes. Newly-created dead wood can contribute to beetle outbreaks for a few months--but this pertains to specific bark beetles and at particular times of year (check with you Extension office for more information). For beetle-killed trees, by the time they are noticeably dead and the needles have turned color, the beetles have already emerged. At this stage, the dead trees now support a different group of deadwood boring beetles that do not spread to live trees, and there is no point in removing these trees to prevent bark beetle infestations. The woodpeckers they support will help control future outbreaks.

What happened on our property is likely typical of how new snags and down logs develop on recently logged land. During the past 35 years, we completed two commercial understory thinnings, making some modest income, and speeding growth of the remaining larger trees. We started leaving snags in the mid 1970's but these were only about 12 inches diameter. As the years went by, these small snags fell and many were left on the ground. They were replaced by slightly larger dying trees. Over time the retained snags and down logs increased in size and number. Only in the last five years have there been a few dead trees over 24” diameter. But now there are many more snags, and at least a few of them are getting big enough to work for nesting cavities. What has especially improved is what you could call the “pantry capacity.” There is just much more dead wood to harbor all kinds of insects, rodents, and other small creatures that make up the foundation of the food chain. If we can achieve our goals, the big birds may be still here fifty years from now for our great-grandkids to enjoy.

Goals for Snag and Down Wood Retention

Good
Better
Best
(In clumps scattered over property)
Snags
0-20 inch diameter (dbh)
4 per acre 10 to 20 per acre 21-30 per acre
Snags
over 20 inch diameter (dbh)
2 per acre 4 to 8 per acre 9-18 per acre
Down Trees 20 per acre
(over 10" diameter, 20’ long)
40 per acre
(half over 15” diameter, 20’ long)
Up to 90 per acre
(average 15” diameter, 30’ long)


Resources:
"Advice on Decayed Wood in the Eastside Mixed Conifer Forest;." DecAID Wood Advisor. Web. Jan. 2009. <http://www.fs.fed.us/r6/nr/wildlife>.
Bull, Evelyn. "Pileated Woodpecker Home Range". Journal of Wildlife Management 1992: 335-345.
"Pileated Woodpecker as a Keystone Habitat Modifer in the Pacific Northwest". USDA Forest Service Gen. Tech. Rep. PSW-GTR-181 (2002)
Aubrey, Keith B and Catherine M. Raley. “Coming Home to Roost: The Pileated Woodpecker as Ecosystem Engineer”. Pacific Northwest Research Station SCIENCE FINDINGS Oct. 2003. Web. 2009. <www.fs.fed.us/pnw/sciencef/scifi57.pdf>
Bull, Evelyn, Jane Hayes, and Nicole Nielsen-Pincus. “Looking Out For the Pileated Woodpecker” Pacific Northwest Research Station SCIENCE FINDINGS Jan. 2009. Web. 2009. <www.fs.fed.us/pnw/pubs/qlist0809.pdf>
Bottorff, Jim. “Snags, Coarse Woody Debris, and Wildlife” WA DNR, Web. Jan. 2009. <http://snohomish.wsu.edu/forestry/documents/SNAGS.pdf>

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