Control of Pachystigma pygmaeum with herbicide

Abstract

Animal deaths caused by Pachystigma pygmaeum have reached considerable proportions (reportedly over 70% on some farms) in the Western Transvaal portion of the Bankenveld in some years. In order to investigate methods of eradicating this plant an experiment was laid down on "klipveld" (stony veld) to investigate the effect of Trodon and Fenotrol (active substance Fenac) on the plant. A 7 X 3 factorial design with two replications was used. Herbicides were applied at three different times of the year and their influence on P. pygmaeum and on the sward was investigated for three years following the application of the herbicides. The concentrations of the active ingredients in the Trodon treatments were respectively 0,530 kg, 1,060 kg and 2,012 kg per ha. The Fenac concentrations used were 2,638 kg, 15,877 kg and 29,070 kg per ha. Treatments were applied during January, March and April. The best long term results were obtained with 29,070 kg Fenac/ha applied during April. This treatment gave, on the average, 98,15 percent control with no significant decrease in basal cover and herbage production. The other spray treatments tended to increase the basal cover and herbage production of the sward.

Keywords: herbicides|poisonous plants|controls|animal deaths|Transvaal|Gauteng Province|Bankenveld|methods|eradications|Fenac|swards|treatments|basal covers|herbage production|spraying