Wildlife Tree Studies on Industrial Forest Lands of Washington and Oregon

1. Wildlife Tree Studies on Industrial Forest Lands of Washington and Oregon Remote Sensing Detection of Snags In Root-Rot Pockets Creation of Snags Using Mechanical Harvesters Fungal Dynamics In Snag Formation Will Littke and John Browning Weyerhaeuser Forestry R&D Centralia, WA Ed Arnett and Richard Schmitz Oregon State University

2. Harvest practices over the past 100-years have changed the structure and complexity of managed forests. Cull-Removal Reduction in butt-rot and bole decay fungi and those species associated with fire Phaeolus schweinitzii. Laetiporus sulphureus Even-age Management Reduction in importance of defect and decay organisms which flourish under uneven-age forest structure (Phellinus pini, mistletoe, Echinodontium etc.)

3. Snag density and quality has also diminished as a consequence of harvest activities, stand conversion (hardwood to conifer etc), machine operability and out of concern for worker safety. Residual snags left in the boundary of harvest units pose a reduced risk to harvest and planting personnel, but the utility of this practice is limited

4. Strategy:Determine effectiveness of various snag/green tree location and retention alternatives on wildlife use to develop improved snag recruitment and use models. • Needs: What science is needed to demonstrate that snag/green tree programs provide for cavity-dwelling wildlife? Science can help with this question by addressing the following topic areas: • WHAT – what kind of snags/green trees are to be left, what dimensions/characteristics should they have, what happens to them over time. • NUMBER – how many to leave; single trees; groups?. • WHERE – how to locate and where are they located, at what distribution. • USE – who uses them, when, is it enough?

5. Study 1. Remote Sensing Used In Detection of Snags In Mortality Pockets • Validate Northwest Aerial Reconnaissance (NAR) methodology for detection of mortality on a landscape and stand basis. Two WA study areas chosen as the test site: Yacolt (1075 acres) and Silver Lake (1380 acres). • Evaluate detection and location capabilities for tree mortality within a variety of stand ages from 15-70 years. • Develop GIS maps of tree mortality in survey areas to facilitate ground-truthing for specific mortality causes. • Develop recommendations based on assessment of snag identification and wildlife significance of results.

6. Computer enhanced photo evaluation coupled with GIS can locate mortality centers and display this data against other topographic and stand data platforms Traditional aerial photo evaluation lacks definitive signatures from which to readily locate and evaluate centers of mortality alder alder

7. Age class overlays provide an easy format from which to effectively search for ideal forest structure: large dbh, species, and location Stand age 61yrs Stand age 36 yrs

8. In 39 discrete centers, 200 standing dead trees across all age classes were investigated for mortality agent and for signs of wildlife use.

9. Snag Casual Agents • Mortality centers created by root-rot fungi (Phellinus and Armillaria) were more common (n= 27/35 centers) than those created by other agents (bears 4/35, bark beetles 2/35, other 2/29) respectively. • The data supports the ground survey showing 67% of mortality at Silver Lake and 72% of mortality at Yacolt being caused by root rot fungi.

10. Nesting activity and wood excavation was concentrated in trees with a mean dbh of 30-40 cm

11. In 39-discrete centers Armillaria and Phellinus caused mortality produced viable nesting sites in trees greater than 33-years old. • Viable nesting sites were most often associated with multiple tree mortality centers.

12. Estimates of aerial survey data show that root-rot is creating a large number of snags on a per acre basis. Such scattered mortality on a landscape basis is difficult to detect and manage using traditional ground based survey methods.

13. Root-plates resulting from windthrow of Armillaria and Phellinus infected trees have a high association with nesting sites of birds (Wrens and Flycatchers).

14. Mortality centers of sufficient size and which meet the age (dbh) requirements for a high probability of cavity nesting sites are shown on this map overlay by the red dots. Validation of active nest sites provides an important tool in layout of harvest unit boundaries and wildlife areas.

15. Study 2. SNAG DYNAMICS AND CAVITY NESTING BIRD USE OF TREES TOPPED WITH MECHANICAL HARVESTERS • A study was initiated to test the effectiveness of creating snags by topping trees with mechanical harvesters in clear-cut harvest settings. • Objective: (1) accelerate the establishment of snag habitat; (2) improve distribution across the landscape; and (3) create snags that are operationally safe and practicable.

17. A variety of snag species (DF, WH) and configurations were created across a broad geography of south central Oregon. Adjacent to Stand Buffer Selection in Open Areas

18. Research Outcomes: • Quantify characteristics of created snags (e.g. height, DBH, tree species) in sample harvest units. • Evaluate decay dynamics and persistence of created snags. • Quantify use of created snags by cavity nesting birds. • Model habitat relationships and probability of use of created snags within and among treatments being used by cavity-nesting birds. • Develop recommendations for applying snag toppingprescriptions based on empirical habitat models.

19. Study Findings: Early Observations (0-10 Years) (1) Several created snags already have received use by various species of wildlife, particularly woodpeckers and raptors (e.g., red-tailed hawk). (2) Woodpecker foraging was documented on 50% (558 of 1,117 snags) of the created snags. One to nine woodpecker nest cavities were documented on 21 different trees within 14 different settings; 7 of these cavities occurred in created snags within single-high treatments. (3) Woodpecker foraging and flaking activity was observed on created snags that occurred in all 6 different treatments. (4) Observations of wildlife species using created snags for perching and foraging include the American robin, hairy woodpecker, northern flicker, red-tailed hawk, Stellar’s jay, Swainson’s thrush, and turkey vulture. Additionally, raptor pellets (regurgitated bone, hair and/or feathers by a hawk or owl) have been discovered at the base of some created snags. (5) Day-roosting bats (species unknown) were observed on 3 different occasions under exfoliating bark on 3 different created snags.

20. Study Findings: Fungal Dynamics (A) In first year, activity predominated by bark beetles and ambrosia beetles followed by flathead and round-headed borers. (B) A few of the mechanical created snag trees contained contained pre-existing decay columns caused by Phellinus pini and Phellinus hartigii (limb and bole infections). These were among the first to be exploited by cavity nesters. (C) Early successional decay fungi predominate in other created snags, including; Cryptoporus volvatus, Gleophyllum sepiarium, Schizophyllum commune, Trichaptum abietinus, and Coriolus versicolor. C. volvatus G. sepiarium T. abietinus

21. Preliminary Conclusions- Fungal Dynamics • Pre-existing decay columns by P. pini (as indicated by visible conks) could be a valuable asset in accelerating cavity nest use- a pre-survey of the site could identify more trees making it as “candidate” snag trees for mechanical topping. • Opportunity to follow the work of Catherine Parks (USFS LaGrande) and others and pre-establish decay columns a decade prior to harvest. • It is uncertain if limb pocket rot such as those caused by P. hartigii will facilitate additional cavity nesting activity- This fungus is only now producing visible sporophores in old limb notches, so that its abundance can be fully assessed. • Bark sloughing caused by insect, sap-rot fungi, and occasional woodpecker activity creates habitat for bats and smaller bird species. • One probable future outcome will be the appearance of brown-cubical rot fungi like Fomitopsis pinicola and a more rapid dissolution of these created snag structure.

22. Conclusions: • Technological advances in remote sensing and GIS allows for an increasing ability to identifying and managing forest resources such as snag rich areas in a cost effective manner. • This could also aid harvest planning and forest layouts to protect and enhance existing wildlife resources. • Creation of snag habitat from existing living trees is underway, but will need time to evaluate it efficacy towards meeting wildlife management objectives.