Description:
Astragalus bisulcatus and Oxytropis sericea spp., both in the Fabaceae family, share the same characteristics and are lumped together in almost all the literature, crazyweed has white flowers and Lambert crazyweed has purple-pink flowers.
These plants are perennial. Silky grows a rosette of characteristic “pea” type leaves from the thick tap root. The leaves are pointed, pineately divided; dark green, sparse and low, having fine hairs, lending a greyish appearance.
Leafless stems grow vertically from the rosette, ending in a spike type flower arrangement (as in snapdragon). Stems may be 12 inches tall.
Flowers are white “pea” type flowers with a pointed keel (Lamberts crazyweed is dark pink with a white striped oval above the keel). The flowers develop into hairy, leather like upright pods with long pointed tips containing many dark kidney shaped seeds.
Astragalus - Towgrooved milkvetch grows about 2 ft tall from a substantial tap root. Long leaves are pineate and the leaflets are paired, pairs seem attracted to each other. Leaflets are rounded on the ends and all are hairy
The dark purple branching stems are barely taller than the leaves and are topped with purple flowers as above. The flowers develop into long thin two grooved seed filled pods.
Symptoms:
Poisoning from these two plants is global and “causes tremendous losses annually” in livestock as the “most wide spread poisonous plant problem on western rangelands” and has been shown to affect wildlife as well. Both plants contain the alkaloids selenium and swainsonine, responsible for locoism.
Livestock often seek the plants once they have been poisoned. A mature cow may be poisoned by eating 2 pounds, with strong symptoms and death within 3-4 hours. The toxin paralyzes the hind leg muscles especially and causes rapid heart beat.
Eating a smaller amount over a longer time causes respiratory problems along with milder rear end paralysis. Horses never recover once they are poisoned. Abortions in cattle and sheep are common after plant consumption.
(la plata county weed web site) (James and Nielsen, 1988; Nielsen et al., 1988) (Hook.0 Gray and Oxytropis sericea spp.) (USU plants)
- HOME
- WEED INFORMATION
- WYOMING DESIGNATED PESTS
- MOSQUITO INFORMATION
- WEED MANAGEMENT ASSISTANCE
- WEED MANAGEMENT AREAS
- SEE 2010 WORK AS IT HAPPENS
- AGENCY WORK
- HERBARIUM
- FORAGE CERTIFICATION
- BIO CONTROL
- MAPPING
- EMPLOYEE LIST
- BOARD MEMBERS
- LINKS
Leafy Spurge Growth Habit: Perennial, erect, up to 3' tall, spreading by seed or creeping roots. Leaves: Alternate, long, narrow, ¼" wide and 2" long, usually drooping. Flowers: Inconspicuous, surrounded by large heart shaped floral leaves which turn yellow-green near maturity.
|