Turf & Rec

Features Agronomy
A look at the ‘green tool box’


February 11, 2009
By William Gathercole

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Are we sceptical? You bet. The purpose of this short article is to focus on the maintenance and safety issues that are influenced by the policies encouraged by the environmental movement. As always, we provide this information from an independent perspective. We ask the following question. With existing and looming bans, what are the so-called green alternatives to cosmetic weed control products?

First of all, let's ask a basic question. What is a weed control product? A weed control product, more precisely referred to as a herbicide, is a chemical used to control, suppress, or inhibit plants that have been deemed as undesirable weeds in turf.

What is a cosmetic weed control product? Politicians and environmentalists would say that it is any herbicide used to merely improve the appearance of turf. Are weeds controlled purely for aesthetic purposes? Not really. What are the true effects of weeds in turf? Weeds actually interfere with the ability of turf to grow properly by competing for carbon dioxide, nutrients, sunlight, and water. Weeds can choke out turf.

Herbicides are not to be classified as merely cosmetic, or not. Herbicides are classified as either selective or non-selective. Selective herbicides, such as 2,4-D, will destroy broad-leaved weeds, such as dandelions, with little or no injury to desirable turfgrasses.

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Conversely, non-selective herbicides will destroy weeds, as well as all surrounding vegetation to which they are applied. Two examples of non-selective herbicides are acetic acid and herbicidal soap. These so-called green alternatives are recommended by the environmental movement. They are highly destructive because they are non-selective. In other words, conventional and safe weed control products like 2,4-D may be replaced by green products that are harmful to turf. The green alternatives may not provide much of an improvement. In fact, their use may be a technical step backward.

Herbicides are also classified as either pre-emergent or post-emergent. Post-emergent herbicides, such as 2,4-D, are highly effective in controlling weeds after they have emerged and developed. Conversely, pre-emergent herbicides, such as corn gluten meal, must be applied to create a chemical soil barrier before certain weeds emerge.

They are soil-active products that prevent the germination of seeds or the early growth of seedlings. The environmental movement has falsely given the public the impression that pre-emergent green alternative products like corn gluten meal are just as effective as 2,4-D. In fact, there are absolutely no valid replacements for herbicides like 2,4-D.

Finally, herbicides are classified as either foliar contact or systemic. Contact herbicides may be non-selective, as well as fast-acting. They may provide a quick burn of the foliage. However, contact herbicides may only suppress perennial weeds, which are able to re-grow from unaffected underground roots and stems.

Consequently, weed control applications will need to be repeated often during the growing season. Several of the green alternatives are contact and non-selective, such as acetic acid and herbicidal soap. By contrast, systemic herbicides, such as 2,4-D, are highly effective since they destroy weeds by being translocated throughout the plant. They are more capable of controlling perennial plants. They may be slower-acting, but, ultimately, they are much more effective than contact herbicides. There are no valid replacements for systemic herbicides like 2,4-D.