Yellow starthistle (Centaurea solstitialis L.) and pubescent wheatgrass (Thinopyrum intermedium spp. barbulatum (Schur) Barkw. & D.R. Dewey) were seeded and subsequently thinned to 0, 130, 260, and 390 plants/m2 in a factorial arrangement. Aggressivity coefficients indicated that intraspecific interference became stronger than interspecific interference, based on biomass of either pubescent wheatgrass and yellow starthistle, as the density of both species increased in a 1:1 ratio. Pubescent wheatgrass provided 0.5 to 1.3 times as much intraspecific interference, plant for plant, as the interspecific interference caused by yellow starthistle. Yellow starthistle provided from 1.5 to 4.6 times as much intraspecific interference, plant for plant, as the interspecific interference caused by pubescent wheatgrass. Weekly leaf counts showed that intra- and interspecific interference from yellow starthistle was detectable 6 weeks after emergence. Weekly leaf counts showed that intraspecific interference from pubescent wheatgrass was detectable 7 weeks after emergence; interspecific interference from pubescent wheatgrass was not detectable using leaf count comparisons. Soil moisture at a 10 cm depth was correlated to leaf number of pubescent wheatgrass but not with leaf number of yellow starthistle. This may reflect the greater competitive ability of yellow starthistle. 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.