N.). 6. DEPARTMENT OF AGRICULTURE. 737 



themselves. But the evidence in its favor does not justify recom- 

 mendation of the practice. The worlc must be done when the plants 

 are small. It is very laborious, and there is always danger of dis- 

 turbing the seed pieces or other stalks. For these reasons it is 

 better to control the number of stalks by reducing the number of 

 eyes planted rather than to depend upon thinning. The small potato 

 that sends four to six stalks to the surface does not send as thrifty 

 ones as the section of a large tuber that has the weight of the small 

 tuber and only two eyes. The addition in cost due to the use of- 

 larger tubers is justified by the yield in most years. 



Vine pruning has been tested by one Station, mid uo advantages 

 were secured thereby. 



INSECT FOES AND REMEDIES. 



The potato has a number of serious insect foes. It is a common 

 thing to hear growers lament that disease and insect attacks make 

 their business hazardous, but I am sure that the progressive, en- 

 ergetic producer has no better friends than these so-called foes. The 

 staple crop that is easy of production atfords a minimum of profit 

 because production is heavy. The most careless can secure yields, 

 and the supply exceeds the demand. This would be notably true 

 of the potato if there were no enemies of tihe crop — insects or disease. 

 The best products for the live farmer are those requiring the most 

 skill and care in their production, as competition is limited by the 

 conditions necessary to success. I do not care to assert that the foes 

 of tho potato are desirable, as they make life harder for the ineflicient 

 who must live, but clearh' they do help the energetic. 



As the potato crop becomes old in any section of the country, the 

 foes to it multiply. This is true of insects, and especially so of dis- 

 eases. As soils grow old and are permitted to become deficient in 

 humus so that drouth cannot be withstood well, and as disease and 

 insects increase, the tend^ency in potato production is to shift its 

 center to newer and more remote land. 



In the part of this treatise dealing with this subject, the mass of 

 matter contributed by our Experiment Station scientists is freely 

 drawn ui)on, selection being guided by personal observation and ex- 

 jierience in the field only so far as they come to a practical grower 

 of potatoes. 



The Colorado Beetle. — Probably the best known insect attacking 

 the potato is the Colorado beetle (Do7'i/2?horadecemlmeafa.) "It was 

 first brought to notice," says Professor Geo. C. Butz, "about the year 

 185G. In 1859, it w^as found in the potato fields of the settlers of Kan- 

 sas. In 1861, it was in Iowa, and in 1862, it appeared in 60uthweste'*n 

 47— 6--1902 



