VALUE AND USE
SPECIES: Sonchus arvensis | Perennial Sowthistle 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Perennial sowthistle is good feed for foraging animals such as rabbits.
It is also acceptable as a livestock feed, although not highly preferred [20]. 


PALATABILITY : 
Perennial sowthistle palatability is rated as poor to fair for cattle,
sheep, and horses [6].  Perennial sowthistle is relatively unpalatable
to lambs.  Grazing lambs rejected it 70 to 80 percent of the time when
offered a choice [22].


NUTRITIONAL VALUE : 
Perennial sowthistle has a nutritive value equal to or superior to that
of alfalfa (Medicago sativa).  Crude protein, macro and micronutrients,
in vitro digestible dry matter, and herbage neutral detergent fiber
concentration are listed for perennial sowthistle at three growth
stages:  vegetative, late bud, and mid-bloom [22].



COVER VALUE : 
Perennial sowthistle is generally rated as poor to fair cover for
wildlife, but is listed as good cover for mule deer and white-tailed
deer in North Dakota [6].


VALUE FOR REHABILITATION OF DISTURBED SITES : 
NO-ENTRY


OTHER USES AND VALUES : 
Perennial sowthistle leaves are edible [6,8], and the roots have been
roasted and used as a substitute for coffee [20].


MANAGEMENT CONSIDERATIONS : 
Perennial sowthistle is a noxious weed in 28 states [25] and in Canada
[20].  It infests cultivated cropland, lawns, disturbed areas, meadows,
and pasture [20].  Perennial sowthistle is unlikely to become a noxious
weed in the southern United States because it is not tolerant of hot
climates [49].

Perennial sowthistle continues to spread into less inhabited regions of
Canada, but its expansion may be limited by cold climate.  During a 1986
to 1988 study, perennial sowthistle was recorded for the first time in
Wood Buffalo National Park on the border of the Northwest Territories
and Alberta.  It was found at 9 of 18 sites.  Wein and others [47] fear
it will continue to spread into wetland vegetation that is stressed by
lower peak water flows which have occurred since the Peace River was
dammed in 1968.

Sonchus arvensis ssp. uliginosus was listed as "persistent" in northern
Manitoba.  It was present at low numbers on less than 5 of 42 sites in
1989.  It had a similar abundance and distribution in 1959.  The cold
climate may be preventing reproduction but regular seed input from other
areas may be perpetuating the species [38].

Herbicide application techniques and perennial sowthistle susceptibility
are described [4,20,43].

Two gall-forming flies native to Europe are being studied as potential
biological controls for perennial sowthistle.  Tephritis dilacerata
forms galls on the flowerheads and prevents seed production.  This fly
was released in Canada in 1979 and in successive years but has not yet
successfully overwintered.  Cystiphora sonchi, which forms leaf galls,
was first released in 1981 in Canada and is surviving and reproducing.
Its overall impact on perennial sowthistle in North America is not yet
known [30,31,37].

Related categories for Species: Sonchus arvensis | Perennial Sowthistle