FIELD MICE AS FARM AND ORCHARD PESTS. 



3 



much branched, and may readily be found by parting the grass or 

 remoYing the litter. The runs lead to shallow burrows where large 

 nests of dead grass furnish winter retreats for the mice. Summer 

 nests are large balls of the same material hidden in the grass and often 

 elevated on small hummocks in the meadows and marshes where the 

 animals abound. The young are brought forth in either underground 

 or surface nests. 



Meadow mice are injurious to most crops. They destroy grass in 

 meadows and pastures; cut down grain, clover, and alfalfa; eat grain 



Fig. 2. — Apple t ree killed by meadow mice. 



left standing in shocks; injure seeds, bulbs, flowers, and garden vege- 

 tables; and are especially harmful to trees and shrubbery. The ex- 

 tent of their depredations is usually in proportion to their numbers. 

 Thus, in the lower Humboldt Valley, Nevada, during two winters 

 (1906-8) these mice were abnormally abundant, and totally ruined 

 the aKaKa, destroying both stems and roots on about 18,000 acres 

 and entailing a loss estimated at fully $250,000. 



When present even in ordinary numbers meadow mice cause serious 

 injury to orchards and nurseries. Their attacks on trees are often 

 made in winter under cover of snow, but they may occur at any sea- 

 son under shelter of growing vegetation or dry litter. The animals 

 have been known almost totally to destroy large nurseries of young 



