Rats and mice can cause serious problem on the farm or homestead. The major source of rodent damage is the Norway or brown rat (Rattus norvegiaz). He is ably assisted by his cousins the black rat (Rattus rattus) and the house mouse (Abemusculus). Other relatives, the field mouse and the pine mouse, cause damage to orchards and in gardens.
Rats are among the most ingenious creatures known. They police their population so the number of rats does not exceed the foal supply by killing or driving out weak rats. A healthy rat can fall 50 feet without serious injury, and can swim half-a-mile in open water up sewer lines against swift currents.
Rat and mouse control are linked on the stead or farm. Although mice are more problematic in the house, rats can infest both house and barn and are a more significant problem in sheds and other outdoor buildings.
Sanitation means eliminating sources of food for rats and mice, and destroying rodent nests. Begin sealing all stored food from rats and mice. It does not necessarily mean rat proofing an entire building, since many buildings are impossible to completely rat-proof.
Dried and bagged food of all kinds should be stored in tight cupboards or preferably in jars or tin boxes with tight-fitting lids. Ruble scraps not fed to animals must be scrupulously composted; rat-proof compost tins are desirable, but proper composting will net draw rats.
Food that needs to be cured or hung for long periods of time can be hung in attics, or storerooms in ways that protect it from rodent infestation. One way is to hang the foodstuffs from a wire strung from one wall to another. Simply punch a hole in the center of large metal disks and slip them over the wire about a foot from each wall. Rodents can’t get around the disks. If you have a beam flush against the ceiling of a building, cover both ends of the beam with tin to about two feet from the wall on either end. Rats won’t be able to maintain a footing on the metal surfaces of the beam ends. Drive nails into the beam for hangers.
Don’t let surplus garden crops stand for extended periods or overwinter in the garden. Shred, plow under, or otherwise dispose of anything rats would enjoy, particularly mature sweet corn. Baled straw often contains wheat that was not threshed out properly at harvest-time and rats or mice will burrow into the bales for the grain. Do not store baled straw in a barn, or, if you do, use the bales as soon as you can.
Keep all livestock and pet feed in metal containers. Steel 55-gallon drums are ideal for the purpose, since they can still be purchased cheaply or be had for free. Be careful not to use drums in which toxic chemicals have been shipped or stored and wash all drums out thoroughly. Pieces of roofing tin weighted down with a rock or piece of cement block will cover the barrels. Set the barrels on pallets or a platform to keep them off the ground so they don’t rust out. In four drums you can store all the feed six chickens and a pig need in a year.
Larger farms and homesteads need larger grain-storage facilities. There are many metal bins and cribs on the market. Old wooden cribs can be partially rat-proofed with hard-ware cloth or pieces of roofing tin, but rats will always find a new place to gnaw through.
If constructing new buildings, don’t put wooden or composition floors in them unless you really need them. Of course, rats can get into dirt-floored buildings easily enough but they don’t often stay because there is no place to hide. If you build a building with a floor, build it up off the ground so that a dog or cat can get underneath the building to chase a rat. Feed your barn cats underneath the floor of the building to encourage them to hunt there.
Keep all piles of wood and lumber up off the ground with planks and posts. Get rid of piles of rocks, old boards and junk.
Feed your chickens and other animals carefully so that they finish their grain and don’t spill it. Don’t leave mash or other food out overnight when rats are active. Rats will attack baby chicks, unless the hen fights them off, so any building in which you are raising chicks should be rat-proof.
Poison is a less than completely satisfactory means of eliminating rats and mice. Poisons like arsenic and strychnine are effective killing agents, but rats who watch other rats die a violent death by strychnine seem to put two and two together and avoid the bait. Besides, such poisons are extremely dangerous to children, pets and farm animals, even if placed in bait stations along rat runs.
Rats sometimes learn to avoid the safer, newer anticoagulant poisons that have been so effective over the past ten years. These poisons often require repeated feedings before they will kill and a rat that gets sick may avoid eating the poison again-it seems to associate the odor of the bait with its sickness. Rats have also shown some tendency to become immune to anticoagulants.
Bait must be placed properly to have greatest effect. Place baits in runways or places where rats seek shelter, but cover them well so that domestic animals or children will not find them. A board may be leaned against the wall over the bait, or the bait may be covered with a box with two-by-three-inch holes in both ends. Rats deprived of earlier hiding places by the cleanup of their shelters may be enticed the bait when it is enclosed in a new place.
Mice in the Orchard
Field mice are not difficult to control in the orchard. They rarely burrow below, and they feed on the trunk, not the roots of trees. If the orchard is mulched, be careful to pull the mulch a few feet away front the in the fall. Field mice build nests mulch but are hesitant to run around in then once cold weather sets in. Placing a wire cylinder around the trunk of each tree is also active against field mice.
Pine mice are often very difficult to control. Persistence is necessary. Dig some of them away from the base of the tree in the fall fill it in with cinders. Spread cinders in able to at least three feet from the trunk. The cinders will help prevent the rodents from tunneling in the soil. Regular snap-back use traps can be effective if carefully set in runs.