MEADOWS AND PASTURES 49 



on short branches near the ground. They must be 

 treated as the ordinary perennials. 



Ordinary perennial weeds must be cut off below 

 the crown. This requires the use of the hoe, the spud, 

 or, where very numerous, the turning-plow, which, of 

 course, means reseeding the meadow or pasture. 

 Perennials with underground stems are the most diffi- 

 cult to deal with. Quack-grass (Fig. 8), Johnson 

 grass, and Canada thistle belong in this cla.ss. The 

 surest way to kill them is to harrow out as large a 

 proportion of the roots as possible, and then summer- 

 fallow the land, running over it as often as the weeds 

 get a start with some implement that shaves off a layer 

 of the top soil. Weeds of this class that do not grow 

 very tall may be smothered out by such dense growing 

 crops as millet, buckwheat, sorghum (sown thick), 

 etc. Such weeds may also be killed by cutting them 

 back so frequently that they have no chance to manu- 

 fadlure and store up food enough in their underground 

 stems to keep them alive. 



The weeds which infest grass-lands vary in differ- 

 ent sedlions. In the North, whiteweed (^Erigeron phila- 

 delphicus) is one of the most troublesome. In pastures 

 this can be held in check by mowing, but Vhen a 

 meadow becomes infested with it the best remedy is 

 to plow it up. Sorrel (^Rumex acetosella) is probably 

 the next most troublesome weed in grass-lands in the 

 North. It is particularly troublesome in old grass- 

 lands, and its presence is believed to indicate an acid 

 condition of the soil. A good application of hme, to 

 corredl acidity, and manure or fertilizer to produce a 

 vigorous growth of the grasses and clovers, is said to 



