WEEDS 161 
vitality to the plant. This root may be starved by repeatedly 
cutting off or poisoning the green leaves, or we may cut out 
the crown (from which the leaves spring) and the upper 
part of the root. This latter method is only feasible when 
a comparatively small number of weeds are to be killed, 
as in the case of a few dandelions on our lawns. 
Farm Management and Weed Control. —- It must be borne 
in mind that the farmer has little time to hunt out individual 
species and prevent them from seeding or to cut them out at a 
certain season of the year, or to practice any other very re- 
fined method of exterminating them. The important thing to 
understand is that certain weeds flourish with certain crops 
and certain methods of farming, and that crop management 
involves weed management. A weed-infested farm is evi- 
dence of a poor farming farm. Good farm management 
involves systematic crop rotation, clean tillage, cleaning up 
unsightly waste places where weeds breed, and care in the 
selection of clean seed. Such management is the best sys- 
tem of weed control of which we know. As special meas- 
ures to be employed when necessary, we may mention summer 
fallowing, seeding down to grass, pasturing with sheep, mow- 
ing at certain times of the year, burning the fields, and spray- 
ing with poisons. 
Kinds of Weeds. — There are hundreds of plants that are 
known as weeds, and three or four scores of them may easily 
be found in almost any section of the country that has been 
settled for a generation or more. But the really important 
or aggressive kinds in any community will not exceed two 
dozen, and these the student should endeavor to identify. 
He will find most of them described in the following brief 
list. Generally assistance may also be secured from well- 
informed persons in the neighborhood. 
