Unwanted Guests: The Pests of the Pile

Animal Pests

Given a comfortable or even marginally nourishing environment, pests, as well as beneficial species will show up to “get in on the action.” Rats are probably the least wanted guests of all. With a hospitable environment and plenty of food, their numbers can increase quickly. Because rats can be transmitters of disease, measures should be taken to discourage them from visiting or inhabiting composting areas. It is important to keep high protein and fatty food wastes out of the compost pile, such as meat and fish scraps, bones, cheeses, butter and other dairy products. As an additional precaution, bread and other high-carbohydrate wastes should not be composted.

Dogs, cats, and raccoons won’t usually attempt nesting in the compost, as rats might do, but they are interested in much the same foods. Thus the same restrictions on food wastes are appropriate if a problem exists. Processing raw compost materials within simple structures, such as wire cages and wooden pallet bins is usually sufficient to discourage domestic animals from digging in the pile.

Flies and Related Pests

One of the most important considerations in composting is the control of flies. Many flies, including houseflies, can spend their larval phase as maggots in compost. Though they play an important part in the recycling and breaking down of all types of organic debris, they are unwanted guests around human households.

Garbage, livestock manure, and food scraps can be a media for the breeding and development of a fly population. If adequate control measures are practiced, and materials are covered there will not be a problem.

It is well to note that the life cycle of the ordinary housefly, musca domestica is usually from about 7 to 14 days when conditions are favorable. The time of the various life stages varies with the temperature and other conditions, but on the average, stages are as follows: egg, 1 to 2 days; larva 3 to 5 days; pupa, 3 to 5 days; emergence of young fly, 7 to 10 days; and egg laying by new fly, 10 to 14 days. Fly control measures must interrupt this cycle and prevent the adult flies from emerging so that no new eggs can be laid.

The composting procedures, turning, and systematic cleanliness, which are useful in providing compost of good quality and in destroying parasites and pathogens, are also effective for controlling flies. Initial shredding or grinding to produce a material which can be more readily attacked by bacteria destroys a large number of the larvae and pupae in the raw material. Also, the texture of material shredded to a particle size no larger than 2inches seems to discourages fly breeding.

To control the numbers of these pests, keep attractive food wastes out of the compost pile, turn compost piles frequently (larvae die at high temperatures), cover piles with a dry material that has a lot of carbon in it such as straw or old grass clippings, or bury your food wastes. Fly-breeding can be satisfactorily controlled in most home composting operations during the fly season with a little more effort than is normally necessary for good sanitary composting.