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An Integrated Weed Management Approach to Managing Foxtail Barley (Hordeum jubatum) in Conservation Tillage Systems
Author: Robert E. Blackshaw, Greg Semach, Xiangju Li, John T. O’Donovan, and K. Neil Harker
Date Created: June 09, 1999
Last Reviewed: February 14, 2007
Document Source: Weed Technology: Volume. 13: 347–353.  Summary · A 4-yr field experiment was conducted to determine the merits of combining cultural and chemical controls to manage foxtail barley in reduced-tillage systems. · Factors studied were crop row spacing, seeding rate, and application rate and timing of glyphosate within a spring wheat–flax cropping sequence. · Glyphosate applied preseeding at 400 or 800 g/ha killed foxtail barley seedlings but only suppressed established perennial plants. Glyphosate applied postharvest at 800 g/ha killed 60 to 70% of established plants. · Combinations of preseeding and postharvest glyphosate gave the greatest reductions in foxtail barley biomass and seed production and resulted in the greatest increases in crop yield. · Including flax in the rotation allowed use of grass herbicides such as quizalofop or sethoxydim that effectively controlled foxtail barley seedlings and provided some suppression of perennial plants. · An increase in wheat seeding rate from 75 to 115 kg/ha reduced foxtail barley growth and increased wheat yield in 3 of 4 yr. Increasing the flax seeding rate from 40 to 80 kg/ha or reducing wheat and flax row spacing from 30 to 20 cm provided little benefit in managing foxtail barley or increasing crop yield. · A multiyear approach combining agronomic practices and timely use of herbicides should allow growers to effectively manage foxtail barley in annual cropping systems using conservation tillage.