250 WEED FLORA OF IOWA 



Prof. H. A. Hitchcock in Farmer's Review, says: "The black 

 bind-weed or perennial morning-glory {Convolvulus arvensis), 

 ■which I suppose is the kind meant, is a great pest and difficult to 

 eradicate. If a patch is not too large, heavy mulching is the best 

 way to destroy it. Then watch the patch closely and cut off im- 

 mediately any stray shoot that may appear above its surface. 

 Nothing but persistent watching and the careful cutting off of 

 all parts above the ground will eradicate this weed. ' ' 



Prof. Ten Eyek, quoted in Wallaces' Farmer, states that the only 

 method of culture applicable to large areas which promises any 

 great degree of control or destruction of the pest is very late fall or 

 winter plowing. The plots which were plowed in November (no 

 plowing was done later than November 20th) showed a. very scat- 

 tering and feeble growth of bindweed on April 26th, the date of 

 inspection. 



The weeds were thinner and more feeble also on the unplowed 

 land which produced a crop of sowed cane or sowed kafSt last 

 season, than they were on any of the lots cultivated in intertilled 

 crops. 



Clover Dodder (Guscuta epHhymum Murr.). 



Description. — A spreading, climbing plant; yellowish or reddish 

 with a few minute scales in place of leaves ; flowers whitish or pink- 

 ish in heads, small, globular, urn-shaped; cylindrical tube longer 

 than the nearly erect, acute sepals; scales large-toothed; stigma 

 elongated; style longer than the ovary; stamens exserted, fruit in 

 capsules. 



Distribution. — This weed has long been known as troublesome 

 in Europe and has been more or less common in the Rocky moun- 

 tains on clover and alfalfa. For some years also frequent in the 

 east; becoming more abundant on clover and alfalfa. 



Extermination. — -Where the plant occurs cut down the clover at 

 once and burn. Sow the patch or field to another crop, preferably 

 to small grain or with corn. 



Clark and Fletcher recommend the following treatment: "As 

 soon as the pest is noticed, the infected patches should be at once 

 mown with a scythe and the refuse removed and destroyed. Fields 



