Of all the buildings on the average farm the corncrib is usually in greatest need of rat proofing. Losses sometimes amounting to a fourth or a third of the total quantity of corn held over winter have been known. A survey in a southern State showed an average loss of 5 per cent of corn in storage; in one case 500 bushels were destroyed in one crib during one winter. The amount of this loss would have been sufficient to pay for rat proofing the crib several times over. In building or remodeling a corncrib; therefore, it is most important that it be made permanently rat proof. Probably the most satisfactory method of accomplishing this with the common slat-sided corncrib is entirely to cover the walls and ceiling on the inside and the wooden floors on the under side with woven-wire mesh or hardware cloth, two or three meshes to the inch. A heavy grade of woven wire should be used, 12 or 15 gage, and galvanized after weaving. Painting with a tar or asphaltic paint increases its durability.
Figure 8.—Suggested construction for corncrib: A, Section through wall; B, section through door, which is made of cribbing on vertical battens; the metal band on the wall extends across the door, but is cut and bent Inward at the edges of the door; C, plan of door; D, enlarged detail of Jamb at closing side of door
Another method, and one that is less expensive and quite effective as long as kept in good repair, is shown in [Figure 8]. Wire netting should be carried around the entire crib to a height of 2 feet or more from the top of the foundation. A strip of galvanized iron 8 inches wide should be fastened above the wire netting. The joints between the foundation and netting and between the netting and metal strip must be tight. As rats are unable to gain a footing on the smooth metal and can not climb over it, it is unnecessary to use wire netting above the strip. Care should be taken to join the lengths of metal tightly and to carry the wire netting and strips of metal across and around both sides of doors and door jambs. It is also advisable to provide doors with springs or weights to insure their remaining closed.
B31365
Figure 9.—An inexpensive method of rat proofing a corncrib. It is supported by glazed tiles capped with galvanized washtubs, which, though not attractive in appearance, have successfully kept out rats