Applegate’s milkvetch is a perennial species with clustered, slender, spreading or procumbent stems 25–40 (-90) cm long. Stems are simple or with few branches and are glabrous or minutely strigose above. Leaves are ascending, 3.5–8 cm long, with a very slender petiole and rachis. Leaflets number 7-13 per leaf, are linear or linear-oblong, 0.8–2 cm long, glabrous above and sparsely strigose beneath, with mucronate, truncate, or retuse apices. Flowers are arranged in loose groups of 10-18 in racemes borne on incurved-ascending peduncles 3-6 cm long. Racemes reach up to 7 cm in length, with flowers ultimately nodding. The calyx is campanulate, approximately 0.3 cm long, with triangular teeth less than half as long as the tube, and strigillose with black and partly white or gray-brown hairs. Petals are whitish to light lavender, with the openly notched banner bent upward at an almost right angle and reaching up to 0.7 cm in length. Pods are horizontally spreading or declined, stipitate, narrowly oblong, and slightly laterally compressed, with an abruptly pointed apex. The nearly straight body is 0.8–1.3 cm long and 0.24–0.28 cm in diameter; the slender, straight stipe is 0.4–0.5 cm long. Valves are thin-cartilaginous, green or purplish-mottled, and strigillose. Pod dehiscence starts at the apex and continues downward through the ventral suture. Flowers produce 8-10 ovules each.
Applegate’s milkvetch occurs in flat, open, seasonally-moist floodplain grasslands with alkaline soils. Historically, habitat included sparse, native bunch grasses and patches of bare soil. Mycorrhizal fungi and Rhizobium bacteria must be present in the soil for plant growth and survival.
Limiting factors
Applegate’s milkvetch is endemic to the Klamath Basin in Oregon. A small number of surviving populations, low numbers, and narrow distribution make this species vulnerable to stochastic events. Habitat loss due to agriculture and urban development, alteration of hydrology, fire suppression, climate change, invasive plants, herbivory, and low reproductive rates have contributed to declines.
Data gaps
Describe population dynamics and structure. Conduct genetic studies to assess genetic diversity and isolation. Evaluate the effects of burning and other management techniques on this species. Assess the extent and impacts of herbivory. Describe life stages and resource requirements. Work to better understand arbuscular mycorrhizal fungi (AMF) communities and the viability of population augmentation as a conservation strategy.
Conservation actions
Continue to implement actions identified in the USFWS recovery plan and amendment, including managing and monitoring known sites. Evaluate the potential for establishing new populations in suitable habitat.
Key reference or plan
A U.S. Fish and Wildlife Service Recovery Plan was released for Applegate’s milkvetch in 1998. A U.S. Fish and Wildlife Service 5-Year Review (https://ecos.fws.gov/docs/five_year_review/doc2380.pdf) addressing updated conservation needs for Applegate’s milkvetch was released in 2009. An amendment to the Recovery Plan was released in 2019 updating recovery criteria and addressing delisting requirements (https://ecos.fws.gov/docs/recovery_plan/Applegates%20milk%20vetch%20Amendment.pdf). The most recent 5-Year Review was published in 2024 (https://ecosphere-documents-production-public.s3.amazonaws.com/sams/public_docs/species_nonpublish/19321.pdf).
