Germination trials at The Berry Botanic Garden resulted in 78% germination of apparently good seeds when subjected to eight weeks of cold stratification followed by alternating 50F/68F (10C/20C) and 60% when apparently good seeds were subjected to eight weeks of cold stratification followed by constant 68F (20C). Seeds not cold stratified did not germinate (BBG File).

Experimental burning over a four-year period at a Research Natural Area found that plants were negatively affected by burning in the first year. However, results were positive in subsequent years, as crown area and flowering increased relative to unburned plants (Connelly and Kauffman 1991, Finley and Kauffman 1992 in Clark et al. 1993)

A five-year demographic study at three different sites did not help researchers identify optimal environmental conditions, due to a lack of gradient in environmental conditions. In most years, populations from both upland and lowland sites had similar reproductive output (Finley 1998). The five-year monitoring study did reveal a possible trend towards fewer reproductive plants and greater mortality at one site during the final year of monitoring (Finley 1998).

Erigeron decumbens ssp. decumbens produced few seedlings when directly seeded, even at high density seeding (60 seeds/m2). Encouragingly, transplants had fairly high survival rates, ranging from 33% to 70%, depending on source population and fertilization treatment (Kaye et al. 2000). These transplantation rates were much higher than a previous study had found (Clark et al., 1997). Researchers from the first study noted that roots developed slowly and their high mortality rates were caused by desiccation

Propagation studies:Erigeron decumbens ssp. decumbens can be propagated using above stem cuttings, but success rates for establishment are much higher when vegetative cuttings include a small amount of rhizome tissue. Rhizome cuttings had survival rates if 67% at eight weeks and 33% at 26 weeks (Clark et al. 1997).

Germination trials. Results indicated that scarification is required for germination (Clark et al. 1995). Other studies show that cold stratification can be used instead of scarification

Seed from at least 5 of the 18 locations are stored at The Berry Botanic Garden.

Endemic to the Willamette Valley of Oregon, Erigeron decumbens var. decumbens is very rare. It is threatened by development, competition with weedy and woody species, road construction and maintenance activities, livestock grazing, and farming practices. It was formerly very widespread, but is currently very restricted.

Agricultural and urban expansion (Meinke 1982). Unmonitored burning (infrequent, hot fires) (Meinke 1982). Secondary succession (Kagan and Yamamoto 1987). Road construction and maintenance (Clark et al. 1993). Invasive non-native plants, especial

As of 1993: 18 populations were known, with two on federal land and two on city owned land. These four populations are the only legally protected from development. Since it is difficult to distinguish genetically distinct plants, ""clumps"" of plants were counted. There were approximately 7500 clumps observed in 1993. Populations ranged in size from 1 individual to 2080 ""clumps"" (Clark et al. 1993).

Seed germination and viability tests: Germination trials. Results indicated that scarification is required for germination (Clark et al. 1995). Other studies show that cold stratification can be used instead of scarification. Propagation studies: Erigeron decumbens ssp. decumbens can be propagated using above stem cuttings, but success rates for establishment are much higher when vegetative cuttings include a small amount of rhizome tissue. Rhizome cuttings had survival rates if 67% at eight weeks and 33% at 26 weeks (Clark et al. 1997). Propagation and transplantation studies. Erigeron decumbens ssp. decumbens produced few seedlings when directly seeded, even at high density seeding (60 seeds/m2). Encouragingly, transplants had fairly high survival rates, ranging from 33% to 70%, depending on source population and fertilization treatment (Kaye et al. 2000). These transplantation rates were much higher than a previous study had found (Clark et al., 1997). Researchers from the first study noted that roots developed slowly and their high mortality rates were caused by desiccation. Monitoring and Management studies: A five-year demographic study at three different sites did not help researchers identify optimal environmental conditions, due to a lack of gradient in environmental conditions. In most years, populations from both upland and lowland sites had similar reproductive output (Finley 1998). The five-year monitoring study did reveal a possible trend towards fewer reproductive plants and greater mortality at one site during the final year of monitoring (Finley 1998). Experimental burning over a four-year period at a Research Natural Area found that plants were negatively affected by burning in the first year. However, results were positive in subsequent years, as crown area and flowering increased relative to unburned plants (Connelly and Kauffman 1991, Finley and Kauffman 1992 in Clark et al. 1993). Germination trials at The Berry Botanic Garden resulted in 78% germination of apparently good seeds when subjected to eight weeks of cold stratification followed by alternating 50F/68F (10C/20C) and 60% when apparently good seeds were subjected to eight weeks of cold stratification followed by constant 68F (20C). Seeds not cold stratified did not germinate (BBG File). Germination trials conducted. Germination was essentially zero with no cold treatment, and increased steadily with the duration of cold stratification. Twelve weeks of cold stratification yielded germination from 13% to 44% depending on seed source. Since this species' small seed size makes manual scarification difficult, cold stratification may be a more effective method when germinating large numbers of seed (Kaye and Kuykendall 2000). Germination and viability studies. Addition of Gibberellic acid (GA) (a plant hormone that plays a role in the regulation of seed germination and dormancy) increased germination rates in scarified seeds from 1993. Scarified seeds from 1994 did not have the same response. One hypothesis is that the 1993 seeds underwent after-ripening and were more receptive to GA. There was not an increase in germination rate with GA addition for either seeds that were not scarified or those that had received cold treatment (Clark et al. 1997). Seed viability studies. The viability of E. decumbens seeds that appeared to have a developed embryo ranged from 60-70%. However, overall production of seeds with embryos was only between 2-19% of total seed production. Seed viability did not decline after one year of storage (Clark et al. 1997).

Prescribed burning at federally owned sites. However, this conflicts with air quality standards. The surrounding area is burned for the grass seed producers and it is difficult for conservation groups to obtain permits for prescribed burns as it is feared it will add to the air pollution problem (Kagan and Yamamoto 1987). Manual and mechanical removal of encroaching trees (Kagan and Yamamoto 1987). Base-line data is being collected to determine effects of future management treatments such as mowing and burning on BLM land (Kaye 2000). Seed from at least 5 of the 18 locations are stored at The Berry Botanic Garden.

Long term demographic monitoring to determine information on vegetative growth, reproduction, recruitment, and mortality (Finley et al. 1995). Close monitoring of Baskett Butte population, to determine the effect of diminished reproductive output observed (Finely 1998). Determine if low rate of filled seed production is a consistent pattern and investigate what factors influence production of viable seed (Clark et al. 1997). Determine seed scarification mechanism in the wild to develop a practical method for laboratory scarification and assist in restoration efforts (Clark et al. 1997). Determine appropriate frequency of prescribed burning (Clark et al. 1993). Determine extent of clonality via genetic analysis.

Collect and store seeds from across the range. Seed viability testing, germination temperature and condition optimization, and methods of transplantation (Finley et al. 1995).