Managing pests in the garden starts with observing them for disease and insect pests when walking around the landscape, patio, and deck.
This action is called scouting, which is part of a science-based technology called integrated pest management (IPM).
IPM uses information about the plants, pests, and environment to manage the insect or diseases with cultural practices and minimal pesticide usage in a way that is safe, economical, and socially responsible. IPM involves various tools such as scouting for pests, correct identification of pests, cultural practices, and biological methods.
The goal is to determine the number of insect pests present and control them before economic damage to the plant occurs, instead of eliminating the pest entirely. IPM is not strictly organic gardening. Synthetic and organic pesticides are used when necessary.
A key component of IPM is scouting to know if the insects and diseases are present. If an insect or disease is not found, then a management method or an insecticide is not necessary. Scouting saves time and money.
After scouting, the disease or insect should be identified. Next, the life cycle of the pest is examined to determine when the most effective and appropriate control methods should be applied. These methods may be cultural, biological, and as the last choice, synthetic or organic chemicals. Timing of the control measure is critical.
If the critical time has passed, then a control measure with an insecticide or fungicide would not be effective and would be wasted. For example, the insect called scale, commonly found on fruit trees and ornamentals, spends most of its life cycle under a waxy scale, which protects it from insecticides. The best time to control scale is during the crawler stage. By scouting, you know when the crawlers appear.
With IPM techniques, the level of pest infestation may be low enough that control is not required. Science-based economic thresholds for insect pests have been determined in commercial crops.
If the number of insects found is below the threshold, a control measure may not be required. If the number of insects is above this level, economic damage may occur, and control is necessary.
The level of control is determined by each person. If blemishes or insect damage on fruits and vegetables is acceptable, then you may not worry about controlling the pest.
Consider picking off and smashing low numbers of insects instead of using an insecticide. Hand removal saves time and money when the number of insect pests is small.
Some pests can be managed by removing the infected plant or plant parts. For example, rake up and remove leaves fallen from crabapple trees infected with the disease called apple scab. The leaves are a source of the disease, which can re-infect the crabapple tree.
Cultural practices also help. These would be considered as “going green,” “cultural” or “sustainable” practices. Rotating vegetables in the garden prevents a buildup of pests. Another cultural practice is to allow enough time for plants to dry off after watering before nightfall.
Water on the leaves in the late evening and at night creates the perfect environment for certain diseases to develop on the leaves.
One biological tool in IPM practices includes using insect and disease-resistant varieties. Plant breeders work hard to develop pest resistance in cultivars of vegetables, fruits, flowers, and landscape plants without losing desirable qualities and characteristics.
Another biological tool is the use of pest-specific pesticides. Bacillus thuringiensis is a bacteria which controls caterpillars of various insect families. Only the caterpillars in these specific families are killed. Bacillus thuringiensis is also easier and safer to handle compared to some of the other organic and synthetic pesticides.
The Daviess County Cooperative Extension Service continues to take an active role in educating local growers about IPM and in implementing IPM practices in field crops, orchards, and fresh market vegetable production. The use of IPM in some instances may reduce the amount of crop protectant materials needed. IPM can be used in home vegetable gardens and landscapes too.
If you have an insect that seems to be causing a problem in the landscape or garden and cannot identify it, place it into a small container with white vinegar and bring it to the Extension Office for identification. Do not use vinegar for a moth because the liquid removes the scales on the wings that are used to identify it.
Plants with disease problems can be brought in as well. For trees and shrubs, make sure to bring in three branches, about 1 foot long if possible, that have the affected leaves on them.
For smaller plants, dig up several of them, including the roots, keeping the soil with them. Also, include a healthy branch or plant for comparison. No fee is charged.
Please do not bring in plants that are already dead. Secondary pathogens that live on dead tissue make it almost impossible to determine which organism caused the problem.
For more questions about using IPM, contact the Daviess County Cooperative Extension
Service Office at 270-685-8480 or email@example.com.
Daviess County residents should take advantage of free soil tests sponsored by the Daviess County Soil Conservation Service through a grant. Knowing the pH level and amount of phosphorus and potassium needed to apply to the lawn, garden, landscape, and fields, saves time, money, and the environment. It is not too early to start collecting soil from the lawn to determine its fertilizer needs. Lawns perform best when fertilized in the fall.