Temperature studies of termite colonies in living trees.

Abstract

Temperatures inside colonies of Coptotermes acinaciformis and C. frenchi in living trees are well above those recorded in neighbouring, uninfested, parts of the tree. Temperature readings in a colony of C. acinaciformis varied from 33 to 38°C, i.e. 13-20 degC above that at the centre of the tree trunk. The winter temperatures are associated with the aggregation of termites in the nursery. The movement of termites in the colony was reflected in changes in the nursery temperature. The nursery temperature of a C. frenchi colony showed little diurnal variation; throughout the year the temperature varied from 27 to 36°C, the highest temperatures being recorded in November when alates were present. The tree insulated the C. frenchi colony against fluctuating air temperature in much the same way as a mound insulates a colony of C. lacteus. Temperature studies of this kind have been useful in assessing the results of insecticide treatments.