Control of problem weeds of maize on the Transvaal Highveld (South Africa). II. Datura stramonium L.

Summary As was described in a previous publication, the influence of a number og herbicides and herbicide mixtures which are being used for the post‐emergence control of weeds in maize on the Transvaal Highveld, have been tested for their efficiency in the control of problem weeds. Both the percentage mortality and percentage dry mass difference between the test plants and the controls 10 days after application of the respective herbicides were used as bioassay methods. Datura stramonium L. was very susceptible to most of the herbicidal treatments up to the nine‐leaf stage. The reason why it is considered a problem weed should perhaps be sought in the erratic germination of its seeds over a number of years, thus evading common practices of weed control.