saltmarsh caterpillar


Many gardening practices can be included in mechanical control such as the use of barriers or hand picking insects. Mechanical control methods usually are more practical for a small garden than for a large one. They can be used singly or in combination to obtain desired results.

Preventive devices and barriers are often are easy to use, although their effectiveness varies. Such devices include:

Handpicking of insects and insect egg masses insures quick and positive control. This method is especially effective with foliage-feeding insects such as tomato hornworms, potato beetles, and squash bugs.

Gardeners can use a stream of high pressure water to dislodge insects from plant stems and leaves or even kill them directly. Aphids and soft-bodied insects are likely to be damaged directly by the water stream but many are also dislodged and do not find their way back to the plant. Spider mites can also be washed from leaves with streams of high pressure water. However, sometimes the mites may survive and start colonies on adjacent plants. Water also increases humidity around the leaves which may help to bring spider mite infectations under control. Care should be taken to use water pressure only on sturdy plants to avoid plant damage.

Various types of traps are reportedly successful in reducing garden insect numbers. For example:

Resistant Plant Varieties | Cultural Controls | Mechanical Control Methods

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