672 DOMESTIC ANIMALS, DAIRYING, ETC. 



San Jose scale. Several correspondents of the Biological Survey have 

 affirmed its efficacy in protecting trees from both mice and rabbits. 



Mechanical contrivances for protecting young orchard trees are 

 many. Where protection from rabbits only is required, woven wire 

 netting is recommended. This should be made of No. 20 galvanized 

 wire, 1-inch mesh, such as is often used for poultry netting. For 

 cottontail rabbits rolls 18 inches wide are recommended, but as a pro- 

 tection against jack rabbits wider material is safer. The wire is cut 

 into 1-foot lengths, and one of these sections is rolled into shape about 

 the trunk of each tree, the ends being brought together and fastened 

 at several places by means of the wire ends. No other fastening is 

 needed. The wire is not in contact with the trunk and may be left on 

 the tree permanently. It will probably last as long as the tree 

 requires protection, and the cost of material need not be over 1% 

 cents for each tree. For young evergreens, material of the same kind 

 1 foot wide and cut in l^-foot lengths will give excellent protection. 

 If trees are to be protected from both rabbits and mice, materials of 

 closer mesh must be used. Wire window-screen nettings is excellent 

 for the purpose, and the cost, when permanence of protection is con- 

 sidered, is not great. 



THE BROWN EAT. 



The rat undoubtedly is the worst mammalian pest known to 

 man. The losses through the destruction of property by these rodents 

 amount to millions of dollars annually in the United States. Aside 

 from their destruction of property the rat sometimes becomes a potent 

 factor in the distribution of disease germs. This animal is not a 

 native to this country, but was introduced from the Old World about 

 the middle of the eighteenth century. It is also called the gray rat, 

 house rat, barn rat, wharf rat, and Norway rat. It was not known on 

 the Pacific coast until after 1851. 



Breeding. Climate and food supply greatly affect the multipli- 

 cation of these rodents. It increases most rapidly in a moderately 

 warm climate and with an abundant supply of food. The number 

 of litters produced a year is not definitely known, but it probably 

 varies with local conditions. Some observations show that about 71 

 days intervene between litters. The average number of young at one 

 birth is between 8 and 9. The period of gestation may be said to be 

 about 21 days. The young are blind and naked when born, but 

 grow rapidly, and the females are capable of breeding when less than 

 three months old. 



Food of Rats. The brown rat is practically omnivorous, that is, 

 they eat readily all kinds of grains and seed, fruits and vegetables, 

 meats, fish, and various animal products. The chief damage done by 

 rats in the United States is through the destruction of grains, poultry, 

 eggs, game, and other birds, although sometimes they become very 

 destructive to fruits and vegetables. 



Natural Enemies. There are many natural enemies of these 

 rodents; among the more prominent may be mentioned the various 

 Jdncls of hawks an4 qwls, as well as skunks, weasels, minks, etc. 



