Great Plains Gardening

By Edith Koeller

July 16, 2004

Hot July weather seems to have arrived permanently. With the recent rains most of our vegetation has really been growing---especially the weeds. It makes one wonder why our "good" crops don’t grow as quickly, doesn’t it? Some of you may have used an herbicide earlier in the year to control this particular problem. If so, and it has worked well, good for you! Those of us that did not, are out there in the cool of the morning and evening trying to get rid of the weeds so the garden plants can have the nutrients to grow that are being stolen by them.

I’d like to touch a bit on pesticides this week. Herbicides are considered one of the pesticides under federal law and are regulated as such. Also included under the term are repellents, growth regulators, defoliants, attractants, fungicides, and insecticides to name a few. Many people believe that if a product is called "organic" or "naturally occurring" it is not hazardous. This is not so. Each product needs to be considered as a hazard, and care must be taken to follow label directions carefully.

There are several terms used to describe how a pesticide works. Control poisons are those that act when the pest comes in contact with the product. Stomach poisons work when the pest had eaten the product. The systemics are the products that when applied move through the sap of plants or the blood of animals to accomplish the desired result.

A fumigant is a gas that kills when absorbed or inhaled by the pest. Translocation is a term used to describe the movement of the pesticide from one part to another of a plant. An example of this is Round-up, which is absorbed through the leaves and down to the roots where it works. Selectives work on a limited group of plants or animals. An example of this is 2,4-D when applied to lawn for weed control. It kills the broadleaf weeds but not the grasses. The non-selectives are the ones that work on a broad range of pests. For instance, Round-up will kill most non-woody plants upon leaf contact.

There are three terms to describe when a pesticide is applied and the terms are self-explanatory: preemergence…before weeds germinate, preplant…applied before planting and postermergence…applied after germination and growing. Postermergence can also be applied after the crop has begun growing.

Pesticides can be applied in a number of ways. Band application is done by placing the pesticide in a strip or band along the crop row. Broadcasting is simply that…a uniform application over the area being treated. Dipping is the complete or partial immersion of a plant, animal or object into the pesticide. Drenching is the saturation of the soil with the product while directed applications aim the product at a certain portion of the object being treated. The term, foliar, refers to the application of the product to leaves. In-furrow refers to the applying of the product directly in the furrow with the plant or seed. Side dressing is like banding…applying the product along the side of the plant row. Soil incorporation is tilling or watering the product into the soil after application and spot treatment refers to applying to a specific small area.

There are four types of pesticides…organic, certified organic, synthetic and synthetic organic. Technically speaking, organic refers to products that have a carbon base. Most man made pesticides are carbon based. Organic is used quite often to refer to products that occur naturally in nature, but some of these can be technically considered in-organic. Did you know that some of our more toxic pesticides are naturally occurring "organic"? The term, certified organic, refers to products "grown under strict regulations limiting inputs to naturally occurring products," Synthetic often refers to products manufactured by man while synthetic organic is a term used to identify carbon based products developed by man. Many of our new pesticides are lab improvements of naturally occurring materials.

This information comes from the Pesticide Safety for Home Gardeners notebook given to us during our Master Gardener training classes.

Until next time…