Head Smut, Ustilago bullata on Slender Wheat Grass, Elymus trachycaulus, introduced along the Norman Wells Pipeline, district of Mackenzie, Northwest Territories

Abstract

Vegetation and related studies to evaluate environmental mitigation along the Norman Wells to Zama Pipeline, included observations on the invasion of Head Smut, Ustilago bullata on Slender Wheat Grass, Elymus trachycaulus (sensu lato) (=Agropyron trachycaulum), a major component of the initial post-construction seed mix used along the pipeline for erosion control. This Pipeline Project involved the largest and most extensive revegetation program to date in the boreal forest and the discontinuous zone of the Northwest Territories. Potential host grasses were uncommon in the adjacent boreal forest area in the Territories; however disease introduction or re-introduction remained a risk even where certified seed mix components from outside the Territories were thought to be uninfected.