Garden Composting & Insects

Compost Heaps

• To understand why insects are attracted to compost heaps, you first need a basic understanding of what compost heaps are and why gardeners use them. By throwing discarded food, leaf and lawn debris, grass clippings and other organic materials onto a compost heap and allowing it to fully decompose, the nitrogen and other nutrients in the organic matter is broken down, producing a soil that is optimal for plant growth since all the nutrients from the organic matter have been imparted to the soil.

Insects Commonly Found in Compost Heaps

• Insects that you are most likely to find in a compost heap are many and varied, so many, in fact, that Cornell University's Agricultural Extension divides common compost insects into three categories. Primary consumers include microorganisms such as fungi and bacteria as well as small insects such as earthworms, millipedes and sowbugs. The category of secondary consumers includes mites, beetles, flatworms and nematodes while the category of tertiary consumers includes certain species of centipedes, beetles and ants.

Function

• The insects enumerated by Cornell University are divided into each category by their function. Primary consumers eat the organic matter thrown into the pile by the composter, thereby releasing the organic matter's nutrients into the compost soil. Secondary consumers eat primary consumers and eat the organic matter as well. Tertiary consumers eat the secondary consumers and occasionally help decompose the organic matter as well.

Insects and Composting in Perspective

• Successful composting relies on the functioning of a complex ecosystem of insects, micro-organisms and other invertebrates. Certain species of insect are attracted to decaying or dead organic matter whereas others are attracted to living tissue and matter, so the presence of insects in a compost heap should be considered a blessing rather than a scourge. The more insects there are in a compost heap, the more complete will be the decomposing of matter and the more nutrient-rich the soil will become. An abundance of flies on a compost pile is a nuisance at the most, one that can be remedied by burying food scraps deeper in the pile where flies cannot reach them.