THE ALUMNI JOURNAL 173 



BENEFITS OF A PLANT EPIDEMIC. 



In a recent address on the diseases of plants, A. F. Woods, of the 

 United States Bureau of Plant Industry, calls attention to the fact that 

 we may often secure aften an epidemic immense varieties of plants by 

 collectine those that have survived. He says, as quoted in Science 

 (New York. October 28) : 



"Our ideal, of course, is to cultivate plants that can, in the largest 

 measure consistent with other requirements, fight their own battles. 

 Observation and experience have given us a large amount of informa- 

 tion on adaptability to conditions and resistance to disease, which 

 remains to be classified and digested in order to be made generally 

 available. We often neglect to reap the benefits of a destructive 

 drought, a cold wave, an epidemic of disease, or the failure of a crop, 

 by neglecting to study and save zvhat is left. The few straggling plants 

 left do not appeal to the average man. He plows them up or turns in 

 the hogs. But the man familiar with nature's methods sees in these 

 survivors resistant strains and saves the few straggling plants for seeds, 

 with the hope that the few survivors may have some peculiarity trans- 

 mittable to progeny, making them resistant to the factor that caused 

 the general destruction of the crop. In this way originated the wilt- 

 resistant cotton, wilt-resistant cowpeas and flax, and cowpeas and 

 tobacco resistant to nematode or root-knot. Strains of red clover 

 resistant to awthracnose (a disease which, in many sections of the 

 South, makes it impossible to grow ordinary non-resistant clover), 

 were also originated in this way. * * * In some of the older and 

 more thickly populated parts of the world, necessity has forced the 

 saving of the last straw. This is why we find the drought-resistant 

 durum wheats in the dry regions of Russii and Asia and around the 

 Mediterranean, the alkali and drought-resistant alfalfas and other for- 

 age crops in the same regions, a cold-resistant alfalfa in Siberia and 

 Northern Manchuria, the cold-resistant winter wheats of Russia, and 

 other crops too numerous to mention. Hundreds of years of culture and 

 selection, forced by poverty and necessity under forbidding conditions 

 of cold and drought and disease, have made those sections veritable 

 storehouses of good things, but what nature and necessity have not 

 produced fo.r us we can in large measure do for ourselves. We can 

 combine the cold-resisting quality of the trifoliate inedible orange 

 with the fruit qualities of the tender sweet orange : the disease-resistant 

 quality of the citron with the fruit quality of the edible melons ; the 



