Autumn is an excellent time to apply horticultural oil. The oil smothers many soft-bodied insects and hard-shelled scales that are impenetrable to many insecticides, and can therefore help control some of the most stubborn insect populations. Applications are directed primarily at killing overwintering pests such as aphids, mites and scale before they can become active in the spring and cause plant injury.
The primary way horticultural oil kills insects is by suffocating them. The oil blocks the spiracles through which insects breathe. It also disrupts the metabolism of insect eggs and the ability of some insects to feed because the oil makes it difficult for them to crawl, causing them to starve to death and preventing them from spreading diseases from plant to plant. Additionally, the oil repels many insects looking for winter homes. Horticultural oils also act as fungicide against powdery mildew, rust and leaf spot on some plants.
These oils are desirable to use because they are safe for people and pets since the excess oil evaporates and dissipates quickly, so there is no toxic residue left behind. These treatments are an effective and ecologically friendly way to handle many insects and even some diseases.
Branch Tree & Landscape Service | Contact Us