There is increased pressure to reduce pesticide use in agriculture. Importers of our products are concerned with products that are harmful to bees, such as products with endocrine disrupting properties and general broad-spectrum products that may be detrimental to the biodiversity levels of the environment. Just as important is the sustainability of our farming enterprises, and a balance between pesticide usage and environmental and ecological sustainability need to be found.
Conservation agriculture is fast gaining momentum in South Africa. Because macadamias are tall, dense, fast-growing trees they are difficult to spray with even the best equipment. SAMAC is currently funding research on sustainable solutions for South African farmers. The list of SAMAC registered pesticides are examined, and although it is evident that a considerable portion of these products are environmentally safe products, it’s effect on the environment and honey bees in particularly will be discussed.
A recent study regarding the efficacy of farm level control of nut borer and false codling moth indicates highly erratic levels of control. Reasons for this will be discussed in the talks as well as farms that were successful in managing these intractable pests.
The key pest, however, is stink bugs and here our options for environmental control are more limited. Broad spectrum products are used out of necessity which creates imbalances, requiring yet more spray applications. Options for monitoring as well as alternative methods of control will be discussed.
Thrips have been giving the macadamia industry trouble the last few years. Threshold values are not available yet and control strategies will be discussed. Thrips damage is exacerbated by dry and warm conditions and may become nearly unmanageable if these conditions persist. These insects are primary pests, but numbers could increase significantly if certain broad-spectrum products are used. The possibility of resistance will briefly be discussed.
Macadamia felted coccid is a new menace and the link between this pest, bark borers and possibly Botryosphaeria will be discussed.
To conclude: It is envisaged that pesticides will always form a very important part of the production of quality macadamia nuts. The nature of the products and how we will be using them will probably change considerably over the next decade.