THE AMERICAN BOTANIST 135 



Getting Rid of Dandelions. — Some apprehensive land- 

 owners are after the dandehons early and late each spring and 

 after a good deal of back-breaking labor digging them out fail 

 to see that their premises are any more free from dandelions 

 than some indolent neighbor who refused to dig a weed. As 

 a matter of fact, the man who refuses to dig dandelions except 

 for "greens" has much reason for his view of the case. Dig- 

 ging dandelions may actually have the effect of multiplying 

 them since the roots can send up new shoots and usually do so, 

 thus producing two or more where the one was originally. 

 Moreover, the open spot left where a plant was dug forms just 

 the right seed bed for new weeds to grow. Possibly the best 

 way to get rid not only of dandelions but other weeds in the 

 lawn, is to feed the grass well, set the lawn mower rather high 

 and let the grass run them out. Most of the weeds that trouble 

 the lawn are such as require an open space in which to spread 

 out their leaves. Letting the grass grow tall obliges these 

 plants to lift their leaves and the mower gets them. Grass can 

 endure this frequent shearing, but the other plants cannot. 



The Increase of Dodder. — Many years ago the clovers 

 in the United States were free from dodder {Cuscuta sp.) al- 

 though the botanists were well aware that in Europe clover 

 and lucerne (called alfalfa in the United States) were often 

 attacked by this interesting parasite. Between twenty-five 

 and thirty years ago the first specimen of dodder attacking 

 clover was sent to me, and from that time to the present there 

 has been a notable increase in the amount of dodder in the 

 country. Each year I have my attention called more and more 

 forcibly to the fact that dodder has come to be a very serious 

 menace to the grower of clover and alfalfa. We have here a 

 most interesting example of how a parasite may invade a 

 country and spread with a good deal of rapidity. Apparently 



