School of Forestry

Northern Arizona UniversitySchool of Forestry

Michael R. Wagner, Ph.D. - Professor Emeritus

Research Interests

Insect/tree interactions

Interactions Between Trees and Insects for Model Systems

Forest insects, fungi, and parasitic plants form complex interactions with their hosts. These interactions define the role these organisms play in patterns and processes of forest ecosystems in the western coniferous forests. Essential ecosystem processes such as plant succession, nutrient cycling, and decomposition are largely controlled by these agents.

Likewise, production of valuable commodities, including solid wood products, paper, recreational opportunity, and wildlife, may be limited by these agents. This spectrum of interactions-from historical concern for insects, fungi, and parasitic plants as pests to the essential ecological role of these organisms-defines the breadth of our research program.

We are studying the interaction between insects and trees for a series of model systems, including pines and pine sawflies, elms and elm leaf beetle, poplars and folivorous insects, native locust and several feeding guilds, and an important African, tropical timber species (Iroko) and gall-forming psyllids. In each model system, we are attempting to understand basic insect biology, mechanisms of host-plant resistance, and the influence of environmental factors on mechanisms of resistance. Among resistance mechanisms, we have studied anatomical characteristics, nutritional value, and defensive chemistry (e.g., terpenes).

Current research is also examining how ecological restoration of fire-adapted western ponderosa pine forests influences the biodiversity and community structure of selected insect guilds, land-application wastewater treatment systems, plant-tissue culture, biology and ecology of forest pests, silvicultural and mechanical control of pests, herbivore impact on host plants, and sustainable development of natural resources worldwide.