Canadian Forest Service Publications

Some factors affecting herbicidal activity of glyphosate in relation to adjuvants and droplet size. 1992. Prasad, R.P. Pages 247-257 (Vol. 11) in L.E. Bode and D.E. Chasin, Editors. Pesticide formulations and application systems. American Society for Testing and Materials, Philadelphia, PA, Standard Technical Publication 1112.

Year: 1992

Issued by: Pacific Forestry Centre

Catalog ID: 3284

Language: English

CFS Availability: Order paper copy (free)

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The influence of four adjuvants (Ethokem, Multifilm, Regulaid and Tween-20) and four spray-droplet sizes (159, 332, 447, 575 micrometers) on efficacy and crop tolerance with a glyphosate formulation were investigated for white birch (Betula papyrifera L.] and white spruce [Picea glauca (Moench) Voss] under greenhouse and laboratory conditions. It was found that some adjuvants (Ethokem, and Tween-20) enhanced the effectiveness of glyphosate sprays without damaging the crop (white spruce) species. Tests with 14C-glyphosate showed greater penetration and translocation by birch leaves when an adjuvant was used. Of the four droplet sizes tested, small droplets (159 micrometers) of glyphosate were more phytotoxic than large drops (575 micrometers). The implication of these findings in relation to herbicidal action of glyphosate on forestry species is discussed.