An important inoculum source of Leptosphaeria maculans and L. biglobosa (syn Plenodomus spp.), the pathogens that cause black leg in Brassicaceae crops, is infected plant residues. The general acceptance of conservation tillage in the Willamette Valley, Oregon, USA, has enabled a build-up in the amount of residue on or near...
The climate of the Pacific Northwest is in flux, and existing forest ecosystems are stressed and poised to shift in fundamental ways, with or without human intervention. This dissertation probes the nature of forest responses to environmental change through investigations of morphology and genetics of three species of alder co-occurring...