CONVOLVULACEAE (CONVOLVULUS FAMIL Y) 327 
not be carried about because of the danger of infection. Culti- 
vated crops should then be grown for some years before the land 
is again used for clover or alfalfa. 
Spraying with Arsenite of soda has been found in some cases to 
be satisfactory, a solution of one pound of the poison to ten gallons 
of water being used. The clover and the alfalfa were also much 
injured, seemingly killed by the treatment, but recovered and made 
new growth from the roots after having been relieved from the 
strangler’s grip. A twenty-per-cent solution of Iron sulfate has 
also been found to be effective on alfalfa fields, killing the parasite 
and apparently destroying the crop; but, as with the arsenical 
treatment, new growth sprang from the roots. 
FLAX DODDER 
Cuscuta Eptlinum, Weihe 
Introduced. Annual. Propagates by seeds. 
Time of bloom: June to August. 
Seed-time: Late August to October. 
Range: Wyoming, Idaho, the Dakotas, and other states where flax 
is cultivated. 
Habitat: Flax and alfalfa fields. 
The coiling stems of this species have somewhat less of the 
reddish tinge that characterizes the Clover Dodder. The flowers 
are yellowish white, and the tube of the small, five-lobed corolla 
does not spread like a bell but is often slightly constricted just 
below the lobes like the mouth of a vase; stamens included; 
scales short and broad, notched at apex and toothed only part- 
way down the sides. The seeds are very much smaller than the 
flax seeds, of course, and might very readily be removed from 
them if it were not for a habit that this Dodder has of dropping 
seeds in pairs, which cohere, making them nearly as heavy as 
those of the flax, though of different shape. But seed from 
Dodder-infested flax fields, if intended for sowing, should be 
rejected at any price, and even when intended for linseed-oil 
manufacture, flax-seed should be very carefully cleansed from all 
contamination of Dodder-seed. 
Means of control the same as for Clover Dodder. 
