Results
(as of June 1998)

Summary of the Status of the Target Species

Of the four target species, only Lecanora conizaeoides appears to have colonized a significant area in western Oregon and Washington. In addition to a few previously known sites in Vancouver, B.C. and Seattle, it is now known from numerous sites in Seattle as well as two sites in Portland, Oregon.

Phaeophyscia rubropulchra is still known from only one site in the Pacific Northwest. This location is in second-growth Pseudotsuga-Tsuga forest on Lookout Point (Neitlich & McCune 1997). This site is downwind (east) of Portland in the low mountains between Portland and Mount Hood, just south of the Columbia River Gorge.

Punctelia subrudecta is known from widely scattered sites in low-elevation urban and rural areas of western Washington and Oregon. This is the only one of the four target species that we believe may be native to this region. Nevertheless, the species appears to respond positively to agricultural and other human activities, so future increases in the Pacific Northwest are expected.

Physcia millegrana, the quintessential pollution-tolerant species of eastern North America, is still unknown in the Pacific Northwest.

1998 Survey Results

Table 1. Site Statistics for 1998 Survey

• 50 sites were surveyed (see list).
• 545 trees were sampled across all 50 sites
  (523 trees sampled, representing 30 known genera
  (21 trees of unknown genus
  (1 telephone pole with Lecanora conizaeoides included)
• 36 of 545 (6.6%) total trees sampled had "hits" (occurrences of the target species)
• 10 sites had hits of at least one target species.
• 108 trees were sampled at the 10 sites where hits were recorded.
• 36 of 108 (33.3%) trees sampled at those 10 sites had hits.
• Deciduous hardwood tree genera sampled: Acer, Aesculus, Alnus, Betula, Cornus, Crataegus, Diospyros, Fagus, Fraxinus, Ginkgo, Hippocastanea, Ilex, Juglans, Liquidambar, Liriodendron, Magnolia, Malus, Platanus, Populus, Paulownia, Prunus, Pyrus, Quercus, Rhamnus, Robinia, Salix, Sorbus, Styrax, Tilia, Ulmus, Unknown.
• Other substrates sampled: 3 Arbutus, 2 Rosaceae, 1 Pseudotsuga, 1 telephone pole.

The four Punctelia subrudecta hits occurred at sites where Lecanora conizaeoides was also present. No individual trees had both Lecanora conizaeoides and Punctelia subrudecta hits.

14 of 32 (43.8%) of the categories of trees had the target species (categories = 30 genera + 1 unknown + 1 other).
18 of 32 (56.2%) of the categories of trees had none of the target species.

Bark Roughness

Initially it was hypothesized that Lecanora conizaeoides occurs most frequently on smooth-barked trees. Data from 101 trees that could be classified as having either smooth or rough bark from sites where hits were recorded were included in a 2-way table (Table 1). We performed a chi-square test of independence of the target lichen species Lecanora conizaeoides and Punctelia subreducta on bark surface roughness. Unknown and Other trees were not included, except for 1 Pseudotsuga and 1 telephone pole that both had hits of Lecanora conizaeoides and could be classified as rough and smooth, respectively.

Table 2. Two-way table of data from sites where hits were recorded and trees could be classified as having smooth or rough bark. Row percentages are in parentheses.

	Target Lichen	Target Lichen
Bark Texture	Present	Absent	Totals
Smooth	8 (42.1%)	11 (57.9%)	19
Rough	27 (32.9%)	55 (67.1%)	82
Totals	35	66	101

There is no evidence that presence of Lecanora conizaeoides and Punctelia subrudecta is dependent upon whether tree bark is smooth or rough (p = 0.45 from a chi-square test with 1 d.f.).

Relationship of Target Species to Dominance Types

Chi-square analyses were performed to test for dependence of the target species Lecanora conizaeoides and Punctelia subreducta on trunk dominance types. Data from all 545 trees sampled were included in four two-way tables (Tables 3-6), one for each of the four dominance types examined (lichen, moss, algae, and bare bark).

• Target species were more likely to be present on trees that were >20% bare (p = 0.004; Table 3) and on trees with >20% algal cover (p < 0.001; Table 4).
• There was no evidence that presence of the target species depended on whether trees had >20% or <20% lichen cover (p = 0.47; Table 5).
• Target species were more likely to be present on trees with <20% moss cover (p < 0.001; Table 6).

To summarize, trees with high algal cover, low moss cover, and largely bare trees were >20% all had higher occurrences of our target pollution-tolerant species than expected by chance. Presence of the target species appeared to be independent of the amount of lichen cover on the substrate.

Table 3. Two-way table of presence-absence of target species in relationship to area of the trunk covered by bare bark (see methods). Row percentages are in parentheses.

	Target Lichen	Target Lichen
Dominance class	Present	Absent	Totals
>20% Bare	27 (9.6%)	255 (90.4%)	282
<20% Bare	9 (3.4%)	254 (96.6%)	263
Totals	36	509	545

Table 4. Two-way tables of presence-absence of target species in relationship to area of the trunk covered by algae. Row percentages are in parentheses.

	Target Lichen	Target Lichen
Dominance class	Present	Absent	Totals
>20% Algae	15 (24.2%)	47 (75.8%)	62
<20% Algae	21 (4.3%)	462 (95.7%)	483
Totals	36	509	545

Table 5. Two-way tables of presence-absence of target species in relationship to area of the trunk covered by lichens (see methods). Row percentages are in parentheses.

	Target Lichen	Target Lichen
Dominance class	Present	Absent	Totals
>20% Lichens	20 (6.0%)	315 (94.0%)	335
<20% Lichens	16 (7.6%)	194 (92.4%)	210
Totals	36	509	545

Table 6. Two-way tables of presence-absence of target species in relationship to area of the trunk covered by moss. Row percentages are in parentheses.

	Target Lichen	Target Lichen
Dominance class	Present	Absent	Totals
>20% Moss	1 (0.4%)	261 (99.6%)	262
<20% Moss	35 (3.4%)	248 (87.6%)	283
Totals	36	509	545

Herbarium Records

Lecanora conizaeoides
USA. WASHINGTON: King County, Seattle, near Ravenna Park, 47o40'N 122o20'W, 100 m, on old wooden fence and Prunus, McCune 22788, October 1995; on Aesculus, McCune 22789, October 1995.

Phaeophyscia rubropulchra
USA. OREGON: Multnomah County, 1 km SW of Lookout Point, 12 km NE of Sandy, 45o29'N 122o08'W, T1S R5E S13, on dead Pseudotsuga in root-rot gap in dense 50-year-old Pseudotsuga - Tsuga heterophylla stand with heavy Acer circinatum understory, 750 m, October 1994, Neitlich 461 (herb. Neitlich).

Punctelia subrudecta (north of California and west of the Continental Divide)
CANADA. B.C.: . Vancouver, University of British Columbia, near Woodward Library, on trunk of deciduous ornamental tree, 49o15'N 123o10'W, April 1986, Goward 86-54. Noble (1982) cites two specimens from the Vancouver area, but without exact localities: 3627 and 4604, found on Pseudotsuga and Holodiscus. Goward & McCune (1994, p.158) mapped two localities in B.C., possibly the two Noble specimens cited above. We know of no other records farther north in the coastal states and provinces.

USA. OREGON: Benton County, Corvallis, Oregon State University localities, ca. 44o34'N 123o16.5'W: (1) Jefferson Avenue across from dormitory, on Liquidambar styraciflua, McCune 20453 (herb. McCune), June 1993; (2) NE of Benton Hall, on Paulonia, one thallus, October 1997, Rikkinen & McCune (not coll.); (3) on boulevard strip in median of 30th St west of tennis courts, about 10 individuals on Quercus macrocarpa, E. B. Peterson ______, (herb. Peterson); Corvallis, near entrance to Lutheran cemetery on Highland Drive north of town, 44o36'N 123o16'W, 100 m, on Pseudotsuga trunk, several thalli, McCune (not coll.). WASHINGTON: Skamania County, Carson, St. Martins Rd., 45o43.6'N 121o47.8'W, T3N R8E S28, on Pseudotsuga trunk, John R. Davis 2392, November 1992 (herb. McCune).

Physcia millegrana
None.