The Effect of Weed Control Method on Soil Nutrient Availability and Growth of Different Hybrid Poplar Clones.
Ryan D. Hangs1, W.R. (Bill) Schroeder2, and Kenneth J. Greer1. (1) Western Ag Innovations, #3-411 Downey Road, Saskatoon, SK S7N0R4, Canada, (2) Prairie Farm Rehabilitation Administration, Agriculture and Agri-Food Canada, Shelterbelt Centre, Box 940, Indian Head, SK S0G 2K0, Canada
During the early establishment phase outplanted hybrid poplar seedlings are the most vulnerable to lethargic growth or mortality because of interspecific competition with non-crop plant species for available soil moisture and nutrients. Consequently, there is a need to develop practical vegetation management practices that are not only successful at controlling non-crop plant species, but also cost-effective for producers looking to minimize their input costs. The objectives of this two-year study were to: i) evaluate the effects of different combinations of within-row (plastic mulch, herbicide, and control) and between-row (tillage, herbicide, and control) vegetation management practices on soil moisture, nutrients, and temperature and the early growth of four hybrid poplar clones (Walker, Assiniboine, WP-69, and Hill) and, ii) assess the relationship between growing season soil nutrient supply rates, measured using in situ burials of ion exchange membrane (Plant Root Simulator™-Probes), and growth of different hybrid poplar clones. Determining the effects of different vegetation management practices on growth-limiting edaphic properties and subsequent seedling growth should help to support effective management strategies, in terms of selecting an efficacious and cost-effective weed control strategy that promotes the establishment and growth of hybrid poplar seedlings, while minimizing the input costs incurred by the producer.