A wetting agent was applied by sprinkler irrigation to nitrogen-fertilized plots on a burned watershed in southern California. The wetting agent decreased the total production of mustard (Brassica nigra and B. Campestris) and increased the number of ryegrass seedlings (Lolium rigidum and L. multiflorum). Where a wetting agent was applied, the moisture conditions at the soil surface were more favorable for seedling establishment and the grass was favored over mustard. In a subsequent laboratory experiment, the wetting agent suppressed mustard seedlings but had a lesser suppressive effect on ryegrass. The differential phytotoxicity was presumably responsible for much of the difference between grass and mustard seedling establishment in the field test. Nitrogen fertilizer increased total plant production and in combination with the wetting agent further enhanced the establishment of ryegrass, but not mustard. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.