Second Report on Potato Culture. 57 



given no potatoes were thrown out because of sun burning. Tlie 

 potato loves a moderately cool, moist soil, and the hilling process is 

 not adapted to produce these conditions. In the case of the two 

 plats mentioned above, the falling off in yield of potatoes on the plat 

 receiving hill culture means the present season a loss of $24 per acre, 

 as the potatoes were sold direct from the field for 65 cents per bushel. 

 The general results, with culture, verify the results obtained in 1896, 

 /. <f., that in the ordinary season about seven to nine cultivations with 

 a fine toothed implement are likely to give best results. As the vines 

 of the potatoes spread so as to cover a portion of the space between 

 the rows, the cultivating implement should be made narrower so that 

 it will not come into too close contact with the plants. 



Insect Enemies of the Potato. 

 Leaf Flea Beetle {Crepidodera cucumeris). 



In this section the first insect which attacks the foliage of the 

 potatoes is the little flea-beetle. In "case of a dry spring their depreda- 

 tions are much worse than doing wet weather. They appear soon 

 after the potatoes are above ground and begin their work upon the 

 leaves, and their presence may not be noted except by the careful 

 observer until they have seriously damaged the foliage. If the vines 

 are disturbed, the beetles will immediately hop off. Their w^ork is 

 evidenced by light colored spots v.'hich appear on the foliage soon 

 after it has been injured. Unless measures are taken to prevent or 

 check the work of this beetle, the plants may become seriously 

 weakened. 



While no practical method has been determined for killing these 

 beetles, yet for two seasons in succession they have been largely driven 

 from the potatoes by the timely use of Bordeaux mixture. (Directions 

 for making this mixture are given on page 69.) While this mixture 

 does not kill the insects, it seems to be obnoxious to them in some way 

 and causes them to migrate to other feeding grounds. The use of the 

 Bordeaux mixture thus early in the season will serve as a preventive of 

 the early blight. By using Paris green in conjunction with the Bor- 

 deaux mixture that great insect enemy of the potato crop the 



Colorado Potato-Beetle [Dorypuora decenili?ieata) 

 may be destroyed if any have made their appearance thus early. 



