sylvaticum (false-brome) and Centaurea debeauxii ssp. thuillieri (meadow knapweed) Survey 2008

Prepared by Rory Nichols, December 2008

INTRODUCTION—

By 1985, 14 species of noxious weeds had been observed at Silver Falls State Park (see Appendix A for complete list) (Bluhm 2006, ODA 2008). However, recent surveys of SFSP have added two more noxious weeds to the park (Nichols 2008a).

Centaurea debeauxii ssp. thuillieri (CEDE, meadow knapweed) is a hybrid derived from European species: C. nigra and C. jacea. The Department of Agriculture (ODA) has listed CEDE (listed by ODA as C. pratensis) as a noxious weed (B List) and was first observed on the Cieslak property in fall 2007 (ODA 2008, Nichols 2008b). CEDE typically invades moist sites such as ditches, roadsides, fields, meadows, open forest, and stream banks. CEDE seed is spread by streams, vehicles, heavy equipment, hay, recreationists and wildlife. It is not known when or how CEDE was introduced to SFSP—perhaps from past thinning projects, or most likely from the dumping of yard debris due to its concentration at a park gate off a county road. CEDE seed may lie dormant in the soil for probably a few years. CEDE sometimes resembles other park species, especially when only basal leaves are present. The invasive C. diffusa has been observed in the park but current status is unknown (Bluhm 2006, Nichols 2008b).

Brachypodium sylvaticum (BRSY, false-brome) is a grass native to Europe, Asia, and North Africa; and listed by the ODA as a noxious weed (B List) (ODA 2008). Oregon has become the North American hub for BRSY as a 1939 Lane County collection is the earliest known record (OFP 2007). McDonald-Dunn Research Forest near Corvallis has one of the largest infestations; surveys show that BRSY spread from 1,649 acres in 1993 to 2,591 acres in 2006—a 57% increase in 13 years (Fletcher et al. 2006). BRSY has the ability to invade riparian and upland forests and meadows. BRSY was first observed trailside at South Falls on Mother's Day 2006. It is unknown how or when BRSY was introduced to SFSP. Recreationists can disperse BRSY by getting seed caught on boots and clothing; forestry equipment, vehicles and deer and elk can also spread seed. BRSY looks similar to the native Bromus vulgaris (Columbia brome) and often shares the same habitat. Both species have been observed growing together and the best way to tell them apart is by BRSY's sessile spikelets on the main axis versus Columbia brome's pedicellate spikelets. BRSY seeds may lie dormant in the soil for three to five years.

METHODS—

No formal survey protocol was used. It was decided to survey all official park trails, fire and park roads with the exception of state and county roads. Site information included: unique identification number (e.g. BRSY##), infestation size estimate, date observed, location (UTM NAD83), and any other important information. Any suspicious road/trailside grasses were closely inspected since the common native Bromus vulgaris can resemble BRSY. Also, when

1 large patches of grasses were encountered, only a representative sample was taken by closely inspecting a minority percentage of throughout the patch. Generally, the surveys concentrated on disturbed areas close to trails or roads but occasionally suspicious-looking patches within view of road/trail were inspected especially in areas where past logging operations or other disturbance had taken place. CEDE was largely searched for in a similar matter. Site area is a rough estimate and does not necessarily reflect a high density population covering the entire area; in other words, sites may have infestations that are somewhat sparse over given area. A new site was recorded when observed greater than ten yards away from any other documented site.

RESULTS—

November 20th to December 10th 2008, over 50 miles of trails, fire and park roads were surveyed for BRSY and CEDE. A total of two CEDE populations and 14 BRSY populations were documented. Both CEDE populations were found on the Cieslak property. BRSY was found primarily along the Canyon Trail (6 sites) and on two Lookout Mountain Road spurs (5). Also, Rim and Rackett Ridge trails, and an F-Lot cutoff trail yielded BRSY. See park map in Appendix A for relative locations of BRSY and CEDE and Appendix B for site specifics. Generally, all sites were somewhat patchy; produced seed (except CEDE02) and deposited seed in treadway and margins (right-of-way); and on road and road-like trails, tended to be on margins and in the middle, while on regular trails restricted to margins. BRSY11 was only site found off trail/road.

Figure 1. Looking toward Silver Ridge Road, CEDE01 grows from the white pin flags to beyond the gate (tape is stretched to 100' from beginning of site's west end).

2 The two sites of CEDE are located on Cieslak pond road near Silver Ridge Road.

CEDE01 grows in front of the gate and continues for over 100' along the road east of the gate (Figure 1). CEDE01 is on both shoulders of the road and in the center. The population is beginning to creep up the south side of the road toward the south meadow where the great gray owl habitat improvement project is occurring.

CEDE02 is the beginning of a small satellite population about 200' down Cieslak pond road from CEDE01 (on right shoulder). It didn't appear specimen flowered this season.

BRSY01 is found near South Falls adjacent to the stairs that lead from the South Falls viewpoint to the trail that leads down to the falls. BRSY is mixed with some Bromus vulgaris.

BRSY02 was observed near the Frenchie Falls junction and covers roughly 100 ft2 (Figure 2). This population has begun to spread to the opposite side of the trail (out of frame to the left in Figure 2).

Figure 2. BRSY02 near Frenchie Falls' junction (whole population is not pictured).

BRSY03 is the largest site near South Falls (≈1000 ft2) and begins about 30' up-trail from bench down to the trail junction. BRSY03 extends behind bench down to lower trail (that leads to South Fork bridge below falls). Site is patchy and mixed with native vegetation but covers a relatively large area.

3 BRSY04 is a small, trailside clump (opposite of North Fork) about 80' east of the Rim and Canyon trails fork.

BRSY05 was observed on the Rackett Ridge Trail and is the easternmost site in the park (Figure 3). This population covers about 400 ft2 on both sides and in center of trail, and is mixed with some Bromus vulgaris.

Figure 3. BRSY05 on the Rackett Ridge Trail looking north (tape is stretched to 50’).

BRSY06 is a small, trailside clump downstream of Lower South Falls (out of view from falls).

BRSY07 (Figure 4) and BRSY08 are located near the redwood tank in the southwest area of SFSP. Both sites are along the same stretch of fire road that leads to the old concrete water tank. BRSY07 is the larger of the two sites (≈175 ft2) and west of BRSY08. Both sites are relatively patchy and stretch about the width of the fire road.

4 Figure 4. White pin flags mark clumps of BRSY at site BRSY07 looking east.

BRSY09, BRSY10 (Figure 5), and BRSY11 are located south of redwood tank road at the next Lookout Mountain Road spur (see map in Appendix B). BRSY09 is growing in the roadbed leading to the old log loading area where the largest infestation (in area) is known at SFSP (BRSY10 at 1350 ft2). BRSY11 is a small clump about ten yards to the east (not growing in log loading area but off-road in disturbed forest).

BRSY12 is a small clump that was observed growing along the spur trail on uphill side opposite of North Fork Silver Creek.

BRSY13 is trailside on a connecting spur about midway between the F Lot and the road that leads to Stone Shelter.

BRSY14 is growing along trail margins downstream of . Patch is overhanging trail on uphill (north) side within view of falls.

5 Figure 5. White pin flags represent larger clumps interspersed among other grasses found in BRSY10 (looking ±NW). Note: Area in all directions has been disturbed by recent logging.

DISCUSSION—

This survey found that CEDE is isolated in the park but beginning to create satellite populations, while BRSY is much more distributed throughout SFSP than originally thought. However, both noxious weeds can be eradicated from SFSP since their combined cover is about a tenth of an acre.

Since the only access to the eastern Cieslak meadows is through the infested Cieslak pond road, concerns arise with recent logging and other activities (e.g. late-2007 roadside thinning and late- 2008 Great Gray Owl habitat improvement). With continued disturbance of this area (and no control), it is only a matter of time before CEDE spreads to, and becomes established in the upper and lower meadows near the Cieslak pond road. There is even the chance the meadow across Silver Ridge Road to the west can become invaded. CEDE02 is the first signs of the original population beginning to branch out along the disturbed roadside. In the area of CEDE02, less understory brush exist possibly allowing for just enough sunlight for CEDE to spread and “jump” into the meadow without any further assistance from human disturbance. Currently, this population is relatively small—and if treated—can be eliminated before further costly spread occurs.

6 BRSY infestations threaten the North and South fork canyons—the most diverse areas of SFSP. It is important to be able to find and eliminate all BRSY populations within the park. With infestations near South Falls and the already apparent satellite populations along the heavily-used Canyon Trail, undoubtedly recreationists will continue to transport BRSY throughout the park and Willamette Valley. This is a cause for deep concern given how BRSY has spread throughout McDonald-Dunn Research Forest and “...has an exceptionally broad ecological amplitude” (Kaye 2003).

The only thing that I would have changed was to survey during the summer months for BRSY and CEDE to help increase the chances of finding all sites. Despite being less than ideal, recent surveys helped get a better idea of the scope of both noxious weeds in the park. Prior to this survey, little was known about the distribution and size of the infestations of both of these species. Also, once a site is found, it would be safe to search for more CEDE or BRSY within a 25 or so yard radius of the site to make sure there is not an aggregation of populations continuing off-trail/road especially in areas that have been recently disturbed.

Overall, I firmly believe BRSY and CEDE can be eliminated from SFSP if treated soon. Follow- up monitoring for several years may prove best to ensure no reinfestation occurs from existing seed banks. CEDE and BRSY are capable of being introduced along roads and trails by human disturbance and then branching out into areas off trail/road without any assistance. Also, with the release of the Silver Falls State Park Draft Master Plan—where new trails and other development are proposed—CEDE and BRSY (and other ) will likely spread into these newly disturbed areas via recreation and development if these noxious weeds are not eradicated. What isn't known is the extent to which these species will establish and spread if allowed. Aggressive action now will save money and keep large amounts of herbicides out of the environment.

7 APPENDIX A

Oregon Department of Agriculture (ODA) listed noxious weeds found at Silver Falls List State Park. * Brachypodium sylvaticum (false-brome) B Discussed in report. Centaurea diffusa (tumble knapweed) B Status unknown—not seen at SFSP by author. *C. debeauxii ssp. thuillieri (= C. pratensis) (meadow knapweed) B Discussed in report. Cirsium arvense (Canada thistle) B Found throughout SFSP in disturbed areas. C. vulgare (bull thistle) B Found throughout SFSP in disturbed areas. Conium maculatum (poison hemlock) B Status unknown—not seen at SFSP by author. Convolvulus arvensis (field bindweed, wild morning glory) B Status unknown—not seen at SFSP by author. Cynoglossum officinale (common hound’s tongue) B Status unknown—not seen at SFSP by author. Cytisus scoparius (Scotch broom) B Found throughout SFSP in disturbed areas. **Equisetum telmateia (giant horsetail) B Found in SFDUA and elsewhere. Hedera helix (English ivy) B Status unknown—not seen at SFSP by author. Hypericum perforatum (common St. John's wort, Klamath weed) B In open, disturbed areas at SFSP. Lathyrus latifolius (everlasting pea) B Status largely unknown—observed patch on NE DeSantis property. Linaria vulgaris (common toadflax, butter and eggs) B Status unknown—not seen at SFSP by author. Rubus armeniacus (Himalayan blackberry) B Found throughout SFSP in disturbed areas. Senecio jacobaea (tansy ragwort) B, T Found throughout SFSP in disturbed areas.

* Not listed in W.L. Bluhm's Flora of Silver Falls State Park (1985). ** E. telmateia is a cosmopolitan species that is also a non-weedy SFSP native.

Note: ODA's invasive species list does not realistically cover all weedy species that should be of concern at SFSP: Geranium lucidum, Ilex aquifolium, Phalaris arundinacea, Robinia pseudoacacia, Rosa eglanteria, Rubus laciniatus, Satureja vulgaris, and others.

8 APPENDIX B

BRSY and CEDE locations at Silver Falls State Park.

9 APPENDIX C

Brachypodium sylvaticum (BRSY) and Centaurea debeauxii ssp. thuillieri (CEDE) site summary.

Species/ Date Pop. Size Location Site ID Observed Est. (ft2) UTMs (NAD83) General Area BRSY01 2008/11/20 100 0526942E / 4969659N South Falls/Canyon Trail BRSY02 2008/11/20 75 0526976E / 4969708N South Falls/Canyon Trail BRSY03 2008/11/20 1000 0526990E / 4969654N South Falls/Canyon Trail BRSY04 2008/11/20 10 0529923E / 4970174N North Falls/Rim Trail BRSY05 2008/11/24 400 0530224E / 4968365N Rackett Ridge BRSY06 2008/11/27 10 0526669E / 4970372N L. South Falls/Canyon Trail BRSY07 2008/12/01 175 0527410E / 4966325N Redwood tank road BRSY08 2008/12/01 10 0527446E / 4966346N Redwood tank road BRSY09 2008/12/01 150 0527214E / 4965928N L.O. Mtn. Rd. spur BRSY10 2008/12/01 1100 0527286E / 4965921N L.O. Mtn. Rd. spur BRSY11 2008/12/01 10 0527298E / 4965916N L.O. Mtn. Rd. spur BRSY12 2008/12/05 10 0528660E / 4970298N Twin Falls/Canyon Trail BRSY13 2008/12/08 225 0527209E / 4969745N F Lot/SFDUA BRSY14 2008/12/08 75 0529677E / 4970193N North Falls/Canyon Trail CEDE01 2008/11/22 1350 0526188E / 4969924N Cieslak property CEDE02 2008/11/29 10 0526210E / 4970027N Cieslak property

10 REFERENCES—

Bluhm, W.L. 2006. Flora of Silver Falls State Park. Willamette Valley Chapter, Native Society of Oregon.

Fletcher, R., et al. 2006. McDonald-Dunn Forest Plan Invasive Plant Species Management Plan. www.cof.orst.edu/cf/forests/mcdonald/plan/files/McDonald%20Forest%20Invasive %20Plant%20Management%20Plan.pdf

Kaye, T. 2003. Invasive Plant Alert: False-brome (Brachypodium sylvaticum). False-brome Working Group. www.appliedeco.org/invasive-species-resources/FBWG/ brsybrochure.pdf

Nichols, R. 2008a. Flora of Silver Falls State Park Additions. Unpublished.

. 2008b. Silver Falls State Park Inventory [Draft]. Unpublished.

Oregon Department of Agriculture (ODA). 2008. Oregon State Noxious Weed List. www. oregon.gov/ODA/PLANT/WEEDS/statelist2.shtml

Oregon Flora Project (OFP). 2007. Oregon Plant Atlas. www.oregonflora.org

11 ADDENDUM

Storm Cleanup/Reconstruction and BRSY Seed Dispersal, January 2009.

The map below shows where a recent storm uprooted two Douglas-firs near South Falls. A sizable (≈1000 ft2) population of false-brome (BRSY03) can be found at this site. BRSY03 is thought to be strictly confined in the area shown below and not found on the opposite side of the trail on the uphill or downhill sides. Cleanup and reconstruction work may likely spread seed across the trail into new areas. Cleanup work near other infected sites at SFSP may also aid in spread.

Figure 6. BRSY03 and recent tree uproot site near South Falls.

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