Seasonal changes in the architecture of natural plant communities and its relevance to insect herbivores.

The seasonal changes in plant community architecture and its importance to insect herbivores during the ruderal-early stages of an experimental secondary successional gradient are described. The dominant group of insect herbivores, the Auchenorrhyncha (Hemiptera: Homoptera) are considered together with their host plants, the Gramineae. Here plant structure is analysed in terms of the height profile of the vegetation and its complexity of form. Correlations between insect and plant parameters indicate that the number of different types of grass structure (a measure of architecture) account for 79% and 86% of the variance in leafhopper species richness and total abundance respectively. It is suggested that plant architecture may influence insect herbivore diversity by providing a templet, principally in terms of resource availability, for insect colonisation.