Oregon Oak Communities Working Group
Winter 2003 Meeting,
February 20, 2003
I. Introductions: Jane Kertis, Facilitator. Attendees from variety of federal, state, county, city governments, conservation organizations, consultants, private citizens and landowners. Suggestions solicited for meeting topics. Please join/assist Steering Committee to plan and host meetings.
II.
Joan Hagar, Forest Ecologist, Pacific
Wildlife Research, Corvallis (and PhD Candidate, For. Sci., OSU): Songbirds
in Willamette Valley Oak Habitats
A. Changes in oak habitat at the landscape scale (distributions) and the stand scale (tree form and stand density) have led to changes in bird species abundance. Habitat distribution much more limited, landscape dominated by ag or conifer forest. Isolated trees do not function the same as stand habitat. Stand structure now much denser, large limbs and acorn production limited. Wide crown favors ephiphytes- substrate for arthropods (prey for birds). Limb breakage = cavities. Acorns a food source.
B.
Bird
surveys of 9 oak stands (from Portland area south to Eugene), in ‘94-’96 (3
yrs.). Most abundant spp. = spotted
towhee, Western wood sparrow. Many more
spp. occur than in conifer forest. Of
10 spp. found in oak, only 2 of those also occur widely in conifer.
White-breasted nuthatch is strongly oak assoc., and only in open oak, species
now in decline. Western wood peewee,
black-capped chickadee, and lazuli bunting also assoc. with oak, but not conifer.
C.
Same
stands were surveys 30 yrs ago by Stan Anderson. Recent surveys show decline of 3 spp., and increase in 6 spp. due
to habitat change.
D.
Joan
notes that this is a hypothesis, based on correlation, not
experimentation. Need to test bird
response to restoration, with pre- and post-treatment data.
Q&A: Raptors included in
surveys? No.
Acorn woodpeckers found in Q. kelloggi? Yes, may also nest in
ponderosa pine.
Do oak stands function as migratory corridors for
oak assoc. spp.? No, the distribution is too
patchy, insufficient to form corridor, but birds may concentrate there for
arthropod foraging en route.
Study re: cavities in oak? Dan Gumtow-Farrier, For. Sci., OSU.
III. Bruce Newhouse, Ecologist, Salix Assoc., President Native Plant Society of Oregon: Native Oak and Prairie Habitats of the Willamette Valley.
A. Overview of habitat types.
1. Prairie <5% tree cover
2. Savanna 5-30% tree cover
3. Woodland 30-60% tree cover
4. Forest 60%+ tree cover
B. Seven Willamette Valley savanna plant associates identified, some climax Douglas-fir, some climax oak, and some climax ponderosa pine.
C. Oak assoc. spp. Include lichen (Lobaria pulmonaria, Usnea longissima), fungi (Boletus regius, Collybia spp.) birds, many plants and their associated pollinators, moths and butterflys, white-tail deer, gray tailed vole, townsends mole, and others.
D. False brome, (Brachypodium sylvaticum) is invading the understory of many oak stands to the near exclusion of all other vegetation.
1. 2 centers of spread: NW of Corvallis, SE of Springfield.
2. In progression of typical infestation rates, it is starting at steepest acceleration of spread.
3. Perhaps the worst weed ever in this area.
4. High seed production, tuft expansion (not rhizomatous)
Q&A. Poison oak response to fire? Historical fire regime would have maintained it at low density. Once well established, one fire will have little effect. Perhaps frequent fire would eventually reduce it.
Comment: among the risk factors reducing oak, the financial disincentives currently in place for landowners under well-intended conservation policies must be added to that list.
IV. Tom O’Neal, Director, Northwest Habitat Institute: Historic and Current Oak Distribution with Implications for Biodiversity.
A. Contrast between mapping of past habitat types, including oak is quite coarse. More recent mapping efforts are much finer scale. Regardless, habitat changes are obvious and implications for biodiversity far-reaching.
B. Historical mapping efforts: 1850 vegetation (Or. Biodiversity Proj./Defenders of Wildlife), Cartographic notes from General Land Office Surveys (1850-1870’s?), and 1936 US Forest Service Inventory (cited in ICEBMP). Veg. Typing for the Portland area from the the three efforts compared, show considerable difference in grain, distribution, detail.
C. Current mapping: “Claire Klock” 1998 map, NHI and ODFW cooperative effort, from aerial photos, orthoquads, hand digitized and ground validated. 2 acre min. resolution – much finer than historical.
D. Current Mapping: NFWF/NHI/Eugene BLM oak and pine mapping in 2002 used digital orthoquad as base, ’95 and ’00 air photos (spatially referenced/rectified), integrated landsat imagery, compared with ’98 map, expanded and refined, then field verified. Typed habitat into four types, further categorized by tree size, by amount of canopy closure, and strata. 565 polygons containing oak/pine habitat identified so far. Will be completed and available as a GIS layer in ’03.
E. How to use the information: Quantify habitat and its change and analyze population response by species closely assoc. with oak, using ‘key ecological functions’ (KEF). For example, a peer panel concluded 20 spp. rely on oak habitat for viability, 12 of them bird spp. Can look at the KEFs that each species provides, and how many species within a habitat provide that particular KEF to measure level of ‘redundancy’. The concept may have bearing on ecosystem resiliency…but must consider that exotics may increase redundancy, yet reduce native species, for example. To learn more about the concept and its use, refer to Wildlife Habitat Relationships book, Ch. 6, by Tom O’Neal and Bruce Marcot (see www.nhi.org).
V. Connie Harrington and Warren Devine, Research Foresters, Olympia Forest Sciences Lab, PNW Research Stn.: Current Quercus garryana Studies at the Olympia Forest Sciences Laboratory
A. Research on oak at Olympia Lab began in early ‘90s with Andy Gray studies of oak assoc. small mammals. Ft. Lewis Military Reservation forestry program has triggered and supported much of the recent work. Current studies/products: Oak bibliography, Tenalquot Planning Area simulations, acorn survey, oak regeneration study, fire effects on oaks study, and oak release study. Avail on web: www.fs.fed.us/pnw/olympia (silviculture). E-mail for Connie: charrington@fs.fed.us
B. Bibliography has 800+ entries, web-based version contains links and abstracts. Available hardcopy, too. Includes QUGA and ‘geographically and botanically related’ oaks.
C. Acorn survey – range wide, expanded to BC, Can., need to expand to California. Shows annual and regional patterns. Production can be related to tree and stand characteristics. Results available and compiled for 2001.
D. Tenalquot planning area – 3000 ha, mosaic of prairie, conifer, hardwood, savanna and woodland. Four mgnt. Scenarios simulated using Organon to model growth and EnVision to model appearance. Existing management leads to decrease in oak, other scenario based on restoring GLO habitat types shows different outcomes.
E. Oak regeneration study includes 3 areas of planted oak tagged and measured. Looking for other sites to include – have any?! Various treatment types are compared – use of tubes, mulch mats, scalping, fertilization, etc.
F. Fire Effects on oak (Dave Peters, PI), looks at fire effects on acorn production, bud mortality with temp/duration (using thermocouples in rx fire, and heating chambers applied to buds)
G. Warren Devine presented design, early results of Oak Release Study that includes 4 sites at Ft. Lewis, where 3 levels of oak release from overtopping conifer is being measured.
1. Study objectives: Determine oak release response, determine factors that could predict such response, and study a variety of secondary effects (e.g. microclimate and vegetation)
2. 3 levels of release studied, each level replicated 6 times on each of four sites; plots are oak centered- radius = oak ht. Full release = remove all conifers within plot (avg. of 15 removed/plot), Half release = remove conifer within half oak ht. radius (avg. 6 removed/plot), control = only conifer thinning (avg. 2 removed/plot). Good job of logging, only 2 of 72 oak were damaged.
3. Responses to be measured: 1) short term: microclimate 2) mid-term: epicormic branching of oak, vegetation, acorn production 3) long term: oak growth,
4. Early results since removal in 2001: increase in epicormic branching, acorn production (greatest in full, least in control).
5. Oak and fir understory trees response measured- growth greatest in wide spacing.
6. Microclimate: max. temp up in full treatment, RH min. down in full, soil moisture decreased (at surface and depth) in full tmt.
Q&A: Is vegetation data part of the study? Yes, will be measured in ’02 & ’03.
Increase seen in weeds? Yes, especially skid trails – broom, thistle and foxglove. Exotics were present prior to treatment, but ¾ of cover was native.
Understory treatments to include stump sprouting? Maybe, but not originally included.
Reasons for soil moisture decrease? Possibly increased evaporation and increased transpiration from ground vegetation. Will require additional sampling to conclude. This is cobbly, sandy, glacial outwash soil.
VI.
Tim Bailey, Resource Planner,
Middlefork Ranger District, Willamette National Forest: Jim’s Creek Savanna Restoration on the Middlefork District
A.
638
acre area containing Douglas-fir, ponderosa pine, incense cedar, sugar pine,
and Oregon white oak.
B.
Historically
much more open stand structure. History
frequent/low-intensity fire (perhaps native American burning), of grazing in early
settlement period.
C.
Savanna
structure probably had a dense understory of bunchgrasses. Remnant populations of Festuca californica remain, and have vigorously repopulated in an
adjacent ponderosa pine plantation. No
non-native species on site!
D.
Development
of dense Douglas-fir canopy after fire exclusion, most 100-130 years old. Older ponderosa pine dying, most oak have
been lost.
E.
Inventory
and assessment done, and desired future condition described (“…open forest of
10-15 tpa, composed of Douglas-fir, ponderosa pine, and Oregon white oak, in
roughly equal amounts…”).
F.
Broad
effort to involve public. Recent public
meeting showed general support, favoring a ‘go-slow’ or incremental approach to
restoration.
VII.
Hugh Snook, Ecologist, Marys Peak
Resource Area, Salem District BLM: First
Steps Toward Oak Restoration on the Marys Peak Resource Area
A. Credit for initiating program must be given to
Oregon Oaks working group for raising awareness among federal agencies. Role of feds is minor in terms of acreage,
but can show leadership through demonstration, study and monitoring to leverage
greater conservation on other ownerships.
Marys Peak has done inventory, assessment, and has a variety of
restoration opportunities.
B.
Inventory
– informal process. About 600 acres
(.5% of land base), 15 locations.
C.
Restoration
opportunities – variety of conditions:
1.
Planting
– conversion from conifer back to oak, limited opportunities. Planted 2 ac this year in valley fringe
clearcut, plant more in ’05.
2.
Thinning:
two types: conifer regen. in which oak has re-established can be thinned to
favor oak and manage as mixed spp. stand; young oak stands tend to be
overstocked and thinning would favor open crown structure.
3.
Release
– from overtopping conifer. Beck Road –
28 ac. Oak release incl. Oak thinning, planting. Environmental Analysis completed, in public comment period, on
web at: www.blm.gov/salem.
Proposed for conifer removal in ’03, then fuel and weed treatments, then
planting and Rx burn.
D.
Next
steps – Complete inventory with Northwest Habitat Inst., in cooperation with
other federal units for consistent data format. Thinning, planting, and more
release projects planned. Cooperate
with American Bird Conservation group on public outreach and education. Monitoring and demonstration site at Beck
Road.
Q&A: Studies of oak regen and
oak release – how about a study of regen. thru stump sprouting? Could incl. 3 tmts: flush-cut stumps,
regular stumps, and trees killed with fire (blowtorch)? Good idea! Some study of this planned at
Beck Rd.
Comment: Fed. Agencies could show leadership also
by studying the rate of loss of oak habitat to conifer encroachment.
VIII.
Announcements:
·
Bob
Altmann with American Bird Conservation would like to update group that his
public outreach/ed proposal is getting underway. Includes four components: a hands-on “Landmanager’s Oak
Restoration Guide”, a 2 day Oak restoration symposium, an educational packet
for schoolchildren (grades 4-7), and a small grant program for restoration
activities. ODFW has pledged $15k in
support, but ABC is in search of $4k in matching funds. Federal agencies (BLM) will fund development
of the landowner guide, this group to help review.
·
Patti
Haggerty notes that website will soon be online as a work in progress.
·
SER-NW
is developing a ‘Restoration Encyclopedia’ (working title), to incl. Chapter on
oak. This group could have a role in
review/development.
·
TNC
is spearheading the Forest Legacy Program.
Federal funds available for easements/purchases, and oak savanna is top
priority.