Destructive and Potentially Destructive Insects of Snakeweed in Western Texas and Eastern New Mexico and a Dioristic Model of Their Biotic Interactions

Abstract

The relationships of the principal destructive and potentially destructive insects associated with Xanthocephalum microcephalum (DC) Shinners (threadleaf snakeweed) and Xanthocephalum sarothrae (Pursh) Shinners (broom snakeweed) have been identified and depicted with a dioristic model. Every region of the host plant is utilized by insects in one or more of the following feeding categories: defoliators, fluid feeders, borers, and gall-formers. Roots, stems, leaves, flowers, and fruit each have their own complement of insect associates. A system analysis reveals a complex picture of insect-host plant interactions as well as potential insect-insect interactions. The roles that these insects play in the natural biological control of threadleaf and broom snakeweed are poorly understood but the general information portrayed in the model of their interactions will help future workers to determine the most productive avenues of research.