THE POTATO 867 



best known and probably the most troublesome of the potato 

 insects. Many of our most destructive insects have been im- 

 ported from other countries, but this one is a native of the 

 Rocky Mountain region. It feeds on the buffalo bur in its 

 native, wild state, but it also attacks a number of our garden 

 crops, among which are the tomato, egg plant, tobacco, and 

 pepper, as well as potatoes. The eggs are bright yellow and are 

 laid in clusters on the potato leaf. The eggs hatch and the young 

 larvae begin feeding at once on the leaves, and may entirely 

 devour them if not checked by some poison. The leaves should 

 be entirely coated with the spray as soon as the eggs hatch, as 

 the younger the bugs are the more easily they are killed. Arse- 

 nate of lead is used in the proportion of 3i to 4 pounds to 50 

 gallons of water, or where it is preferable, about J pound of Paris 

 green to 50 gallons of water may be used. Bordeaux mixture is 

 also offensive to them and commonly used in conjunction with 

 these poisons, with the double purpose of controlling certain 

 diseases and assisting in combating the potato beetle and also 

 the flea beetle. It requires about 100 gallons of the spray per 

 acre. It is applied by a spray machine drawn by horsepower, or 

 a hand sprayer may be used successfully on small patches. 



392. The Flea Beetle (Crepidodera cucumeris) . — This tiny 

 flea-like beetle is seen on tomatoes and potatoes when they are 

 small and tender and easily injured. Instead of eating the edges 

 of the leaves, as the potato beetle does, they eat them full of 

 holes and may do as much injury as the Colorado beetle. While 

 it is difficult to control them, yet Bordeaux mixture, to which 

 some arsenate of lead has been added, forms a thin plaster over 

 the leaves which is not to their liking and thus causes them to 

 seek other food. They are much worse where potatoes are 

 grown more than one year in succession on the same ground, so 

 for this reason rotation of crops is desirable. 



393. The June Beetle {Lachnosterna spp.). — The common 

 white grubs or larvae of the May beetles or June bugs are one of 

 the most common pests in field and garden. They are troublesome 

 on newly plowed sod lands, especially when the land had been in 

 grass for a number of years. It is not uncommon to find the 

 potato crop practically ruined under such conditions. They are 

 difficult to control, and rotation of crops, late fall and early 

 spring plowing, allowing swine to work over the land, and allow- 



