Astragalus brevidens Rydb.
Astragalus carolinianus L.
Astragalus halei Rydb.
Astragalus mortonii Nutt.
Astragalus oreophilus Rydb.
Astragalus pachystachys Rydb.
Astragalus spicatus Torr. & A.Gray
Astragalus torreyi Rydb.
Astragalus tristis Torr. & A.Gray
Tragacantha mortonii (Nutt.) Kuntze
Common Name: Canadian Milkvetch
Astragalus canadensis is a herbaceous, perennial plant producing a cluster of upright, branched or unbranched stems up to 100cm tall[
The plant is harvested from the wild for local use as a medicine and a food.
Many members of this genus contain toxic glycosides[
A number of species can accumulate toxic levels of selenium when grown in soils that are relatively rich in that element[
All species with edible seedpods can be distinguished by their fleshy round or oval seedpod that looks somewhat like a greengage.[
N. America - British Colombia and Northwest Territiroes to Quebec, south to California and Georgia
Shores and rich thickets[
]. Rocky and sandy thickets in Texas[
This species is not hardy in the colder areas of the Temperate zone, it tolerates temperatures down to between -5 and -10°c[
]. A very strange report for this species, given that it is found as far north as the Northwest Territories of Canada. It is likely to be much more cold tolerant[
Requires a dry well-drained soil in a sunny position[
Plants are intolerant of root disturbance and are best planted in their final positions whilst still small[
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[
]. Many members of this genus can be difficult to grow, this may be due partly to a lack of their specific bacterial associations in the soil[
Root - raw or boiled[
]. They were often used in a broth[
]. The roots are gathered in spring or autumn[
]. Some caution is advised, if the root is bitter it could be due to the presence of toxic alkaloids[
The root is analgesic and antihaemorrhagic[
]. It can be chewed or used as a tea to treat chest and back pains, coughs and the spitting up of blood[
]. A decoction of the root is used as a febrifuge for children[
]. A poultice made from the chewed root has been used to treat cuts[
Seed - best sown as soon as it is ripe in a cold frame[
]. A period of cold stratification may help stored seed to germinate[
]. Stored seed, and perhaps also fresh seed, should be pre-soaked for 24 hours in hot water before sowing - but make sure that you do not cook the seed[
]. Any seed that does not swell should be carefully pricked with a needle, taking care not to damage the embryo, and re-soaked for a further 24 hours[
]. Germination can be slow and erratic but is usually within 4 - 9 weeks or more at 13°c if the seed is treated or sown fresh[
]. As soon as it is large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter, planting them out into their permanent positions in late spring or early summer, after the last expected frosts.