Weeds in Indiana 109 
fertilizers and drain where necessary. A luxuriant growth of pasture 
or turf grasses, for instance, will crowd out the weeds. 
8. Many grain-field weeds can be controlled by the use of a weeder 
or a spike-tooth harrow in the young grain, a practice that is usually 
more profitable than the use of sprays and other spectacular devices. 
9. Clean cultivation, crop rotation, and the use of smother crops 
will eradicate or control the incidental weeds. A few weeds, such as 
the wild garlic, Canada thistle and dodder must be dealt with by special 
methods. 
10. Co-operation among farmers is an important factor in weed 
control, inasmuch as weeds are a community as well as an individual 
problem. Many weeds, for instance, are disseminated by wind-dis- 
tributed seeds. It avails a man little to eradicate the Canada thistle 
on his farm if the seeds from a neighbor’s land are allowed to reinfest 
the clean fields. Roadside weeds in particular present a problem that 
can be solved by concerted action only. A realization of the seriousness 
of the situation should arouse sentiment in favor of co-operative action. 
Purdue University. 
