58 



Fig. 20. 



- Bindweed, 



Convolvulus arvensis (L). 



A very troublesome weed which wiuds its tough and curling 

 stems around the stalks of various plants, partially chokes them, and 

 thereby hinders their growth. It is a perennial with a very exten- 

 'sive creeping root which penetrates far into the soil, and any piece of 

 the root possessing one or more buds is capable of starting new plants, 

 hence it is necessary to clean implements very thoroughly after they 

 have been used in a field containing this weed. The stems are 

 branched and either trail on the ground or climb by twisting around 

 some other plant. The leaves are rather small, with 2-4 lobes at the 

 base, giving them an arrow-headed shape. The flowers are white or 

 rose-colored and 1 inch across. The seeds, three in number, are large, 

 black, and angular, and are held in a spherical capsule (Fig. 20). An 

 average plant produces about 160 seeds. 



Time of flowering, June-September. Time of seeding, August- 

 October. 



Dispersal — chiefly by means of its creeping roots ; sometimes as 

 an impurity in seed grain. 



Eradication. This is a very difficult weed to eradicate, and care- 

 less cultivation only increases the trouble by carrying the roots from 

 place to place. Salting is recommended by some practical farmers 

 who have succeeded in eradicating this very troublesome pest ; but we 

 cannot speak from experience as to the value of this method of 

 treatment. 



The weed may be kept in check by the frequent introduction 

 of Avell cared-for hoed crops into the .rotation, and the shoiter the 

 rotation the better. The later sown hoed crops, especially rape, are 

 more eflectual than those sown earlier in the season. Before the hoed 

 crop is sown, the weed may be kept in check by going frequently 

 over the field with a broad-share cultivator, so as to cut all the plants 

 an inch or two below the surface without bringing up any of the 

 creeping root-stocks. About the 1st July the land may be sown with 

 rape in drills, say 26 inches apart, and during the early growth of the 

 crop the weeds may be kept in check by means of the horse-hoe, with 

 more or less hand-hoeing. If the land has been well manured or is 

 naturally rich in vegetable matter, the rape will make a rank growth 

 and smother some of the weeds. The rape may be pastured in the 

 fall, and in extreme cases may be followed by another hoed crop, 

 such as corn. If the corn is well cultivated and hoed, most, perhaps 

 all, of the plants will be destroyed. 



lu some cases it may be advisable to summer-fallow, and in such 

 cases it is best not to plow more than is absolutely necessary, but to 



