COTTONTAIL EABBITS. 



11 



permanent to afford protection for an entire winter, and most of 

 those that are lasting are injurious to trees. Coal tar, pine tar, tarred 

 paper, and oils, under certain conditions, are dangerous to young 

 trees. Carbolic acid and other volatile substances afford only tem- 

 porary protection, and must be renewed too often to warrant their 

 use. Bitter substances, like commercial aloes and quassia, are useless 

 against rabbits. 



The most promising simple washes for protecting large trees 

 from rabbits are those containing lime mixed with sulphur or cop- 

 peras in various combinations. Lime alone is not sufficiently per- 

 manent, especially where much rain falls. When mixed with 

 sufficient copperas it has a deep green color and sticks much better. 

 The lime-sulphur wash commonly used to destroy San Jose scale in 

 winter has often proved successful as a rabbit repellent, but its lack 

 of adhesive qualities often makes it fail. The defects may be partly 

 corrected by mixing salt, soap, or a cheap glue with the lime and 

 sulphur while the wash is still hot. 



A poisoned wash of starch and glycerin, tried during the winter 

 of 1913-14 in Idaho by a field agent of the Biological Survey, gave 

 excellent results in protecting young orchards from jack rabbits, 

 and would probably be equally effective where cottontails are con- 

 cerned. The wash is prepared as follows: 



Dissolve 1 ounce of strychnine (sulphate) in 3 quarts of boiling 

 water. Dissolve ^ pound of laundry starch in 1 pint of cold water. 

 Pour the starch into the vessel containing the strychnine and boil the 

 mixture a short time until it is clear, adding 6 ounces of glycerin and 

 stirring thoroughly. When it is cool enough apply with a paint 

 brush to the tree trunks. 



The glycerin and starch adhere well and form a thin coating to the 

 bark. Rabbits attacking the trees will be quickly killed. In the 

 Idaho experiments none of the trees were damaged badly enough 

 to affect their growth and all the rabbits in the orchards were de- 

 stroyed. The method is well worth trying; but care should be 

 taken not to endanger domestic animals. 



MECHANICAL CONTRIVANCES. 



Among the best mechanical contrivances for protecting trees from 

 rabbits are cylinders of woven wire netting. Poultry netting of 

 1-inch mesh, made of No. 20 galvanized wire, will answer every 

 requirement. Rolls 18 inches wide are used for cottontails, and the 

 material is cut into 1-foot lengths. One of the sections is rolled into 

 cylindrical shape about the trunk of each tree and fastened at several 

 places by bending and twisting the projecting ends of wire. No 

 other fastening is needed, but stakes or spreaders may be used to 

 prevent rabbits from pressing the wire against the bark and doing 



