432 



.IX ECOXOMIC EXTOMOLOGY. 



anv i^^rower until he lias first tested it in a small way. White-lead 

 paint is in somewhat the same case, anil, if used at all, should be 

 a])plied only on well-established trees, and should not be mixed 

 with turpentine. 



Lime in the form of whitewash is an excellent application to 

 the trunks and lower limbs, and will in itself serve to keep them 

 measurably free from scale attack ; the wash should not be so 

 thick as to scale of^, and salt should be added to improve its 

 adhesive qualities. When trees are sprayed with Bordeaux mix- 

 ture, the trunks and lars^er branches may be especially well 

 covered or sprayed more than once to insure a thorough coating, 

 and this, repeated at intervals through the season, will serve a 

 similar purpose. Hydraulic cement, or "water lime," mixed 

 with water or, better, skim-milk, to form a thick paint, makes a 

 covering that lasts all season, and has proved about as effective 

 in keeping borers out of peach-trees as anything that I have used. 

 On smaller trees it is as cheap as the paper banding ; on larger 

 trees it is more expensive. In any case, it causes no injury to the 

 most tender l)ark. 



A great variety of other coverings has been used, from a mix- 

 ture of cow-dung and clay to simple soft soap, and in so far as 

 they form a mechanical coating all are good. Whale-oil soap 

 forms the basis of many such washes, and kerosene or carbolic 

 acid is sometimes kdded. It is probable that the carbolic acid is 

 of some use in this connection at the rate of an ounce or two in 

 a gallon of soap mixture ; most of the others are useless, if not 

 actually harmful. 



Keeping the trees clean, free from all abnormal growths and 

 loose, dead bark is always advisable. It destroys the hiding 

 places of any hibernating species, and prevents the formation of 

 cocoons by the larva of the codling moth and other caterpillars. 

 If the trunks are washed with a strong solution of caustic soda or 

 potash, say one pound in two gallons of water, the lichen and 

 other plant growths will be destroyed, and the bark will be 

 cleansed and stimulated. 



To prevent climbing cut-worms, canker-worms or similar crea- 

 tures from ascending a tree, a band of cotton batting can be 

 satisfactorilv used in many cases. Make the band from eight to 

 twelve inches wide, and long enough to go around the trunk with 

 an allowance for a two-inch lap ; tie tighdy at the bottom of the 



