VALUE AND USE
SPECIES: Melilotus alba | White Sweetclover 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
White sweetclover is eaten by all classes of livestock.  It is grown for
hay, used as pasture, and is seeded with other legumes to improve
western rangelands [27,31].  The hay is palatable and nutritious but
must be thoroughly cured.  Partially cured hay can produce a hemorrhagic
syndrome when ingested by cattle.  The toxic substance, dicoumarol,
which occurs only in moldy hay, results from the conversion of nontoxic
coumarin by fungi in moist plants [3].  Sheep and horses are less
susceptible than cattle to the disease.  Bloat can occur in livestock
pastured on white sweetclover, but it occurs less frequently than
animals pastured on alfalfa (Medicago sativa) or true clovers (Trifolium
spp.) [31].

Big game animals, including elk, pronghorn, bighorn sheep, mule deer,
and white-tailed deer consume this plant when it is available
[5,10,12,34].  The seeds are eaten by numerous species of birds and
small mammals, and are especially common in the diets of quail and
partridge [10,12].  Muskrats feed on the roots when other preferred
foods are scarce.  Rabbits eat the leaves and stems [10].


PALATABILITY : 
White sweetclover palatability to livestock and big game animals is
moderately high to high during spring and early summer [4,5,6,45,19,29].
As plants mature, however, they become less palatable because they
become woody and the amount of "bitter tasting" coumarin increases [35].
When in bloom in the summer, wildlife and livestock "relish" the flowers
[13].

Palatability of white sweetclover in several western states is rated as
follows [4,6,29]:

                     CO    KS      MT         ND    UT    WY

Cattle              good  good    good       good  fair  good
Sheep               good  good    good       good  fair  good
Horses              good  good    good       good  fair  good
Pronghorn           ----  ----    fair       good  good  good
Elk                 ----  ----    good       ----  good  good
Mule deer           ----  ----  fair-good    good  good  good
White-tailed deer   ----  ----  fair-good    good  ----  good
Small mammals       ----  ----    fair       fair  good  good
Small nongame birds ----  ----    fair       fair  good  good
Upland game birds   ----  ----    fair       fair  good  good
Waterfowl           ----  ----    ----       good  good  good


NUTRITIONAL VALUE : 
White sweetclover has a well-balanced complement of nutrients during
early growth stages, and when cut and cured properly, makes a nutritious
and palatable hay.  On a dry matter basis, white sweetclover hay
resembles alfalfa hay in metabolizable energy and most digestible
nutrients, but is slightly higher in digestible crude protein [31].
Crude protein content of hay often exceeds 15 percent on a dry matter
basis [22].  Protein content and digestible protein of dry white
sweetclover aerial parts were reported as follows by the National
Academy of Sciences [22]:

crude protein                   15.0 %
digestible protein for cattle    9.9 %
digestible protein for goats    10.6 %
digestible protein for horses   10.3 %
digestible protein for rabbits  10.3 %
digestible protein for sheep    10.8 %


COVER VALUE : 
White sweetclover provides good cover for small mammals, waterfowl,
quail, and ring-necked pheasant [10,14,23,34].

Wildlife cover values for several western states are as follows [6]:

                       MT    ND    UT    WY

Pronghorn             ----  good  fair  poor
Elk                   ----  ----  poor  poor
Mule deer             ----  good  fair  poor
White-tailed deer     ----  good  ----  poor
Small mammals         good  good  good  good
Small nongame birds   good  good  good  good
Upland game birds     good  good  good  good
Waterfowl             ----  good  fair  good


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Seeded white sweetclover generally makes rapid growth, quickly providing
vegetative cover on disturbed areas.  Its chief rehabilitation use is
for erosion control and revegetation of mined lands [14,37].  It grows
well on calcareous and alkaline mine spoils but is not recommended for
use on acidic spoils [14,30].  It is especially important as a
preparatory crop on mined lands because it incorporates large amounts of
nitrogen and organic matter into the soil, which is made available to
succeeding plants [31,33].  Scarified seed is generally sown in the fall
in southern latitudes and in the early spring in northern latitudes.
White sweetclover planting information has been reported in detail
[4,37,40].


OTHER USES AND VALUES : 
White sweetclover makes valuable bee pasture and has long been
recognized as one of the most important of all plants for honey
production [31,37].

Besides its use for hay or pasture, white sweetclover is also used in
agriculture as a soil improvement crop.  Because of its symbiotic
relationship with Rhizobium bacteria, pure stands may add up to 70
pounds of nitrogen per acre (78 kg/ha) to the soil [16].


MANAGEMENT CONSIDERATIONS : 
Control:  First-year white sweetclover plants have a "special growth
period" at the end of summer, when rapid root growth and food storage
take place [21].  This begins about September 1 in the Midwest.  Plants
mowed just prior to the start of this special growth period experience
high rates of winter mortality.  In Ohio, winter kill resulting from
top-growth removal at different times of the year was as follows [31]:

    Mortality                      Cutting Date

75% winter kill         Sept 9 (beginning of root growth period)
53% winter kill         Sept 26 (middle of root growth period)
12% winter kill         Nov 3 (end of root growth period)
 5% winter kill         plants not cut

Additionally, clipped plants that survived the winter showed poor vigor
the following spring, and many died during the summer of their second
year.  

White sweetclover is easily killed with phenoxy herbicides such as 2,4-D
or dicamba, but soil-stored seed is unaffected [31].

Grazing:  For best use of pasture, first year plants can be lightly
grazed in the spring when 10 to 12 inches (25-30 cm) high, but should
not be grazed heavily until after late September.  Pastures dominated by
second year plants should be grazed in the spring and maintained at a
height of about 12 inches (30 cm), which prevents plants from becoming
woody and unpalatable [4,13].

Insects and Disease:  The sweetclover weevil is the most damaging insect
affecting white sweetclover.  In Montana, severe infestations have
resulted in complete failure of new seedlings [29].  Second-year plants
are susceptible to root rot [4].

Related categories for Species: Melilotus alba | White Sweetclover