Will Subterranean Termites Consume Landscape Mulches?

"Subterranean termites live in colonies in the soil in both temperate and tropical regions throughout the world. These termites feed on cellulose and are a major cause of damage to wood in use. Organic tree-based mulches provide many benefits to a landscape, yet recently, questions about whether they could harbor or be a source of food for termite colonies have arisen. In a series of 2 no-choice food experiments, this study investigated whether termites would consume 6 landscape mulches: cypress, eucalyptus, melaleuca, pine bark, pine straw, and a utility pruning mulch, and 5 woods: pine sapwood, cypress heartwood and sapwood, and melaleuca heartwood and sapwood. In the wood experiments, termites consumed pine and cypress sapwood but did not consume the cypress heartwood or melaleuca sapwood or heartwood. In the pine and cypress sapwood, 64% to 77% of the termites survived, while melaleuca and cypress heartwood had fewer than 15% live termites. In Experiment 1, termites ate more of the utility mulch than any other mulch. In Experiment 2, termites consumed all mulches except melaleuca, which was the least desirable food in both experiments. Correlations with chemical characteristics were significant for both nitrogen and phosphorus (r = 0.91 and 0.96), showing that termites preferred mulches with higher N and P concentrations.In both experiments termite consumption was also correlated with 1-year decomposition of mulches in another study. Because termites ate most mulches, further investigation is necessary to determine whether landscape mulches around building foundations could harbor or support termite colonies." [Abstract]