Problem Plant Control Compendium (2012)
Compiled by Kathy van Zyl. Published by AVCASA (Veterinary and Crop Association of SA), Midrand (011 805 2000).
Although billed as the first edition of a new publication, this book is in fact an updated, enhanced version of an earlier book by the same author, entitled "Control of Unwanted Plants", published by XACT in 2005. It is unique among published, readily available literature in that it provides a comprehensive listing of all herbicides currently registered for use against over 130 species of indigenous and alien trees, shrubs, water plants and grasses that can be invasive or problematic.
The main section of the book comprises an alphabetically-ordered tabulation of individual species, each with a listing of the approved herbicide agent for particular types of application (foliar, stump, soil etc), together with registered branded products in each case. Application directions are also summarised. Some species (e.g. Acacia pycnantha, golden wattle) have a single herbicide registered for use (in this case, Molopo 500 SC L5854, with the active ingredient tebuthiuron 500g/l), whereas for others, such as Solanum mauritianum (bugweed), numerous herbicidal agents and over 40 branded products are listed.
All the troublesome alien plants in our area are covered in detail, but so are many other species - e.g. Acacia nigrescens (knob-thorn), Cynodon dactylon (common couch or kweek grass), Dombeya rotundifolia (wild pear) and Ziziphus mucronata (wag-n-bietjie) – that for most of us in the Waterberg would be considered assets rather than liabilities. Indeed, the book could be misleading for those unfamiliar with our indigenous flora because – unlike its previous incarnation, which symbolised each species – it fails to distinguish between those species that are truly alien and/or declared invasives; and those that are indigenous and might only be problematic locally or under particular circumstances. Readers are cautioned, therefore, not to conclude that every species listed in the book is unwanted; they should consult local experts to establish which species in particular should be targeted in the area in which they live.
A second shortcoming of this otherwise valuable compilation is that it inadequately warns users of the dangers (to the surrounding environment) associated with some pesticide agents – MSMA, bromacil and tebuthiuron for example – a deficiency that emphasises the importance of consulting with a herbicide specialist and reading the labelled information carefully when selecting a product for a particular application.
Five appendices tabulate summaries of the same information contained in the body of the text but in different alphabetically-ordered arrangements: lists of active ingredients or agents; brand or trade names; common names of the listed plants; and names and contact details of individual herbicide companies. These addenda provide a useful means of looking up requisite information when only some of the details of the plant or herbicide are known. An accompanying CD-ROM allows the total contents of the book to be stored and accessed on computer.
The use of herbicides in South Africa is rigorously controlled by the Fertilizers, Farm Feeds, Agricultural Remedies and Stock Remedies Act, No. 36 of 1947, and its related regulations. In terms of this long-standing, robust legislation, it is an offence, inter alia, to acquire, dispose of, sell or use any pesticide in a manner other than that specified on the label of the container. Hence the importance of ensuring that the appropriate registered, branded herbicide is identified for a particular application – a role filled admirably by this affordable and user-friendly publication, which should be on the shelves of every conservation-oriented landowner / manager.