Application of glyphosate to cut stumps is broadly viewed as an effective way to control invasive woody shrubs like the buckthorn species (Rhamnus cathartica L. and Frangula alnus Mill.). Since the primary cost associated with this control method is labor, identifying factors that improve efficacy is important. The objective of this research was to determine the effect of glyphosate concentration and soil moisture on the control of buckthorn using the cut-stump method. More than 600 mature buckthorn plants were cut and treated with glyphosate at concentrations between 0 and 41% active ingredient during October in soils varying from dry to moist. While increased glyphosate concentration improved control rates, soil moisture played a dominant role. In moist soils, the impact of glyphosate concentration was insignificant (z=-1.723, p=0.085), and between 40% and 60% of treated buckthorn plants escaped control at all glyphosate concentrations. In dry soils, however, control rates increased significantly with higher concentrations of glyphosate (z=-8.84, p < 10–15), achieving up to 98% control with 41 % glyphosate. Root exudates of two three-year old field-grown buckthorn seedlings that were treated with high glyphosate concentrations in dry soils using cut-stump treatments contained detectable glyphosate comparable to control rates of mature plants. These results suggest that using the highest labeled concentration of herbicide in relatively dry soil conditions will provide optimum effectiveness with control rates up to 98%.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 32 • No. 3