VALUE AND USE
SPECIES: Lupinus sericeus | Silky Lupine 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Silky lupine is readily to moderately available within its range and is
consumed from a moderate to high degree by white-tailed deer, upland
game birds, small nongame birds, and small mammals [6].  In sagebrush
habitats in the River of No Return Wilderness, Idaho, silky lupine
comprised 6 percent of the summer diet of bighorn sheep [8].  Dead
aerial portions of the plant are preferred by bighorn sheep in winter
in Glacier National Park, Montana [32].  The leaves and flowers of silky
lupine are preferred by Columbia ground squirrels [23].


PALATABILITY : 
Palatability of silky lupine in Utah, Wyoming, Colorado, and Montana is
poor to fair for cattle and horses and fair for sheep [6].


NUTRITIONAL VALUE : 
Silky lupine is generally poor in energy and protein value [6].
Nutrient values from plants collected in July in the River of No
Return Wilderness, Idaho, were 26 percent crude fiber; 17 percent crude
protein; 1.09 percent calcium; and 0.21 percent phosphorous.  Moisture
content was 62 percent [8].


COVER VALUE : 
Silky lupine provides fair to good cover for small nongame birds and
small mammals [6].


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Silky lupine is useful in the rehabilitation of disturbed areas
[4,20,29].  Its ability to fix nitrogen allows it to colonize repeatedly
disturbed and low-fertility soils.  It has established in old roadbeds
in abandoned mining towns of Montana [20], and in Grand Teton National
Park, Wyoming [4].  Overall, silky lupine has been given a medium to low
rating for erosion control and long-term revegetation potential in Utah,
Colorado, Wyoming, and Montana [6].  Lupines as a whole have
possibilities for use in management, but more information is needed on
the response of the genus to stand disturbance in a wide range of
habitats [17].


OTHER USES AND VALUES : 
NO-ENTRY


MANAGEMENT CONSIDERATIONS : 
Silky lupine is a highly toxic plant, especially to sheep [15,23].  It
is less toxic to cattle and horses [19], but causes calf deformities if
ingested by cows between 40 to 70 days gestation [15,27,37].  It
produces quinolizidine alkaloids which affect the nervous system of
livestock [27].  Lupines (Lupinus spp.) are responsible for more losses
among sheep in Montana, Idaho, and Utah than any other single plant
genus [19].  Silky lupine is toxic from the beginning of growth in the
spring until it dries in late summer [15,37].  Dried plants are probably
poisonous as well [19].  Sheep are poisoned by ingesting 0.125 to 0.25
pound (0.06-0.11 kg) daily for 3 to 4 days.  Cattle are poisoned by
ingesting 1.0 to 1.5 pounds (0.45-0.68 kg) daily.  Livestock normally
consume silky lupine only when other forage is unavailable [15,37].
The symptoms associated with silky lupine poisoning have been described
in detail [19,37].  Silky lupine is apparently not toxic to wildlife
[6,27].

Silky lupine increases under intensive grazing, and is most abundant
under poor or fair range conditions [16,39,40].  It often forms nearly
pure stands in overgrazed areas [39].  Poisoning of livestock occurs
when poor range management has resulted in overgrazing and depletion of
preferred rangeland species [27].  Where lupine species are common,
ranges should be utilized when other forage is abundant and especially
when lupines are not in fruit [37].  Silky lupine has been controlled by
various esters of 2,4-D and 2,4,5-T [15,37].  Plants should be sprayed
after they are approximately 5 inches (12.7 cm) tall, but before they
bloom [15].  After spraying, grazing should be deferred to let desirable
plant species occupy the range.

Lupines (L. sericeus and L. caudatus) responded with minor changes in
canopy cover to different management regimes in Douglas-fir/pinegrass
(Pseudotsuga mensiesii/Calamagrostis rubescens) habitat types in central
Idaho.  The plants decreased slightly in canopy cover, but seedlings
established when stands were selectively cut or clearcut followed by
mechanical scarification.  There was a slight increase in growth in
stands that were clearcut with no site preparation.  Seedling
establishment and an increase in cover were evident in stands destroyed
by wildfire and in stands that were clearcut followed by broadcast
burning [35].  In ponderosa pine (Pinus ponderosa) types in eastern
Washington, silky lupine increased 1,100 percent in plots thinned with
26-foot (8.0 m) spacing.  There was no increase in unthinned plots [26].
Silkly lupine is the dominant forb in Idaho fescue (Festuca idahoensis)
grasslands of the Bighorn Mountains, Wyoming.  It produces an average of
156 pounds per acre (175.5 kg/ha), and comprises 9 percent of the total
production of all stands [14].

Related categories for Species: Lupinus sericeus | Silky Lupine