The seed that is commercially available in this country as "thistle" is
from an African plant, "Guizotia abyssinica". Although it is in the thistle
family, a better name for the plant and its seeds is "niger." Historically,
nearly all niger seed was imported from Ethiopia, originally as food for
small cage birds but more recently as a magnet for goldfinches, siskins,
etc. I understand that niger seed is also used to produce oil for human use
(food?), and that there are now some commercial niger farms in this country
, I think in Texas.

Although niger seed occasionally sprouts, I seriously doubt that--as a
tropical plant--it would survive for many generations in most parts of
the U.S. Gleason & Cronquist (Manual of Vascular Plants of NE U.S. &
Adjacent Canada) report that G. abyssinica is "occasionally adventive in
waste places in our range."

Unlike black sunflower, niger seed seldom spoils in wet weather and seldom
sprouts in cool regions, so it seems unlikely that it would gain a foothold
in most of the northwestern U.S.

I just wish I'd bought stock in a niger-importing company about 20 years
ago before the big birdfeeding boom hit! In these parts, it's still selling
for $1.30 and up per pound.


Happy Birding!


BILL HILTON JR.
"The Piedmont Naturalist"
Hilton Pond Center for Piedmont Natural History
1432 DeVinney Road
York, South Carolina 29745
(803)684-0255
hiltonb at ctrvax.vanderbilt.edu