Oxytropis campestris var. johannensis

Common Names:
Johann's locoweed, late yellow locoweed, St. John river oxytrope, St. John's oxytrope
Growth Habit:
CPC Number:
Profile Contributors:
Elizabeth J. Farnsworth
Fully Sponsored

Reference Links

ITIS - Tropicos - USDA Plants - Fish & WildLife

Participating Institutions

The following Participating Institutions are custodians for this species in the CPC National Collection:
New England Wild Flower Society

The conservation of Oxytropis campestris var. johannensis is fully sponsored.
Elizabeth J. Farnsworth contributed to this Plant Profile.


Oxytropis campestris var. johannensis is a river-side legume endemic to Maine and eastern Canada. Its deep taproot and compact architecture help it withstand the frequent flooding and ice scour common along wild, rocky northern rivers, and its populations shift along the shoreline when disturbance occurs. Although relatively secure in southern Ontario, the species has declined in extent from 118 km to 28 km of shoreline in its former Maine stronghold along the St. John River (which gave it its common name). Its taxonomic relatedness to the similar but disjunct taxon, Oxytropis campestris var. chartacea (Fassett) Barneby of Wisconsin (U.S. Fish and Wildlife Service 2001, Wisconsin State Herbarium 2001) still need to be resolved; these could constitute the same taxon, meaning the variety is more widespread than previously thought. In any case, populations are threatened by changes in hydrology and sedimentation brought on by damming and riverbed mining and upland clearing, as well as encroachment of invasive species.

Research and Management Summary:
Apart from preliminary taxonomic treatments, no published research could be located on this taxon. However, the New England Wild Flower Society has performed germination trials on it and published a Conservation and Research Plan in 2001.

Plant Description:
Oxytropis campestris var. johannensis is a perennial herb growing 4-55 cm tall with short-stems that emanate from a tap-rooted base. Its pinnately-compound leaves consist of 7-45 hairy leaflets each 5-25 mm long. In July, its flowers form at the end of a leafless stem, clustered into a raceme of up to 14 blooms. The 12-18 mm-long flowers are purple or rarely white, with the typical "butterfly" shape of the Papilionoid group. The plant produces sparsely hairy legumes (pods) that are 1.5-2.5 cm long.

Distribution & Occurrence


Conservation, Ecology & Research