Question: What chemical should I use to control my lawn and garden pest problems?

Answer: Many types of pesticides are available for use including insecticides, fungicides, herbicides, miticides, and nematicides. When using pesticides in a safe manner involves a combination of knowledge, common sense, and to read and follow label directions. When pesticides are used incorrectly there is the potential of poisoning occurring to the gardener, family members, neighbors, pets, and the environment.

Pesticides are grouped by: what they control, chemical nature, and how they work. For example, an insecticides controls insects, herbicides control weeds, and fungicides control fungi. Another method of classification is by chemical nature. The most common are inorganics, plant-derived organics, microbials, and synthetic organics.

Inorganic pesticides are made from minerals including arsenic, copper, boron, lead, and zinc. These types of pesticides are made up of heavy metals. Examples include lead arsenate, Bordeaux mixture, and Paris green.

Plant-derived organic pesticides are made of natural compounds from plants. One example is pyrethrins, which is used in a combination with other active ingredients to control bees and wasps.

Microbial pesticides are made of microscopic organisms that attack pests. Examples are bacteria, fungi, nematodes, and viruses. The most common is Bacillus thuringiensis.

Synthetic organics are man-made. They are mostly non-selective contact poisons and toxic to many different kinds of plants and animals. Pests must come in contact with the poison for it to be effective.

These are all mode of actions in which a chemical may work:

• Contact poisons require the pest to come in contact with the poison. Many of the synthetic organic pesticides work in this manner.

• Stomach poisons must be consumed by pests to be effective.

• Fumigants are gases that kill pests when they inhale or absorb the chemical. An example would be bug bombs.

• Selective pesticides are poisons that only work on certain pests. For example,

2, 4-D herbicide kills broadleaf weeds not grasses.

• Non-selective pesticides kill many plants or animals. For example, carbaryl is used in gardens to kill insects such as the Colorado potato beetle and will also kill bees. Glyphosate herbicide kills just about any type of plant.

• Protectants are applied to plants, animals, and structures as a preventative measure. People have their homes treated with a protectant to prevent termite damage.

Remember to read and follow label directions on the chemicals you select to use. The label is the law.

Reminder: A growing program this year is the “Sampson County Friends of Horticulture”. This program offers monthly “How To” Horticultural Seminars. Please call (910) 592-7161 for more information. Please call the Sampson County Cooperative Extension Center at (910) 592-7161 with your horticultural questions and to register for any upcoming events. Be sure to check out the Ask An Expert Widget at sampson.ces.ncsu.edu for any questions you may have.