Towards costing chemical control of Lantana camara L.

Abstract

Six herbicide treatments are registered in South Africa for the control of Lantana camara L. (lantana). Three of the treatments were selected for a costing analysis of the initial control of lantana, based on their suitability for specific situations in which lantana commonly occurs as a weed. For the investigation, a work study was performed to separate the cost of preparative operations (slashing) and herbicide application. The volume of the registered concentration of herbicide that was applied was recorded to permit costing of the chemical. Approximately 27 man days ha⁻¹ were required to slash medium to dense stands of lantana and 3.5 man days ha⁻¹ for sparse infestations. For chemical treatment of the stumps, imazapyr (Chopper®) in water was cheaper than picloram/triclopyr (Tordon Super®) in diesel owing to the respective costs of the carriers. The application of glyphosate (Roundup®)to lantana coppice was also more expensive than imazapyr application to the stumps. The efficacy of all three herbicides was high. As reinfestation of cleared areas usually occurs, follow-up treatment of lantana is essential. The cost of two seasons of follow-up treatment using glyphosate as a foliar spray was also recorded. The importance of follow-up measures for both budgeting purposes and the effective control of lantana, is emphasized.