Choose a Pesticide With the Narrowest Possible Spectrum

Standard
20170207A.jpg

Most pesticides sold in garden centers have a broad spectrum: they indiscriminately kill anything within their range.

The ideal pesticide would be the one with an extremely narrow spectrum, acting on only one enemy and nothing else. Thus, the impact on the environment would be minimal: a single insect, disease or plant would be eliminated without negatively affecting anything nearby.

Right now, though, most pesticides on the market are quite the opposite: they are broad spectrum products. This includes insecticides that kill all insects, even ladybugs and bees; herbicides that eliminate all broadleaved plants including the lilies and foxgloves in your flowerbed; and fungicides that attack pretty much any fungus, even the ones needed to decompose plant debris and dead leaves.

20170207B.jpg

Btk is a bacteria that only kills caterpillars.

However, there have been some interesting breakthroughs into more specific compounds that affect only a limited range of pests. Think of the highly popular Btk (Bacillus thurigiensis kurstaki), which only kills caterpillars (moth and butterfly larvae) and nothing else, and of beneficial nematodes (Steinernema, Heterorhabditis and others) that only infect grubs, maggots and other insect larvae that chew on plant roots underground.

A lot of very promising research is being carried out in this area. One day, we’ll probably be able to obtain an organic pesticide that only acts on goutweed (Aegopodium podagraria) or red spider mites and absolutely nothing else. That will certainly make gardening easier while reducing any negative environmental effects.

In the meantime, however, apply any pesticide, even an organic one, with precaution, as there is always risk of collateral damage.20170207a

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s