Insecticides

In the home landscape, much can be done to reduce or eliminate insecticide use involving best management practices, including proper irrigation, using adapted plants and accepting low pest damage levels. However, insecticide use may be justified in certain situations. When in doubt, ask your local Extension Office or experienced garden center personnel. When pesticide is recommended, many less toxic reduced risk options exist that have shorter pre-harvest intervals (the wait time required from spraying until food crops can be harvested) when used correctly. This list is not comprehensive but offers some common options. Always follow the label.

Bacillus thuringiensis (Bt): Bt is a naturally occurring gut bacteria found in many insect species. Some strains are toxic to certian insects due to forming crystal-like compounds in insect gut-tracts that inhibits feeding. Products with Bt are especially effective against pest caterpillars. Alternative strains exist that control other insects such as mosquitoes, flies and beetles. Thuricide is a common brand.

Spinosad: Derived from a bacteria was found naturally occurring in the Caribbean, spinosad is effective against many insect pests. Additionally, of the reduced risk options, it is probably the most effective against many fruit pests including western cherry fruit fly and coddling moth. Brands exist with unfortunate names. Look for Fertilome Borer, Bagworm, Tent Caterpillar and Leaf Miner Spray or Captain Jack's Dead Bug Brew.

Azadirachtin or Neem: The active ingredient is derived from pressed fruit of the neem tree in India. It suppresses insect feeding, smothers and repels many insects and also has fungicidal properties. Neem is often blended with other botanical insecticides such as pyrethrins. Look for Fertilime Triple Action, Fertilome Fruit Tree Spray, Fertilome Neem-Py, and Neem Oil Concentrate.

Horticultural Oil: Many oils exist that are useful for smothering dormant and active piercing-sucking insects such as aphids and scales. Oils are often applied in late winter as a preventative. Summer weight concentrations can also be mixed. Most oils must be applied directly to the insect to be effective.

Horticultural Soap: Horticultural soaps are specifically formulated for landscape insect control as compared to products such as dish soap. They are especially effective but must be applied directly to the insect, having no residual properties. Safer is a common brand. Utah State University Extension recommends horticultural soap over homebrew soap mixes because exact mixing instructions exist on the label.

Canola Oil: See horticultural oil.

Pyrethrins: Pyrethrins are derived from a species of chrysanthemum and control multiple insect pests. They are additionally often included in reduced risk fruit tree sprays and blended with other active ingredients. Bayer Natria Insect, Disease and Mite Control and Fertilome Neem-Py contain pyrethrins.

Diatomaceous Earth: Diatomaceous earth does not act as an internal poison. Instead, it is a powder that consists of fossilized diatoms. It feels somewhat like talcum powder. However, microscopically it has the texture of sharp, broken glass. It is used to control soft-bodied crawling insects such as caterpillars. The dust can also get into the joints of hard bodied insects and offer control through rubbing action.

Iron Phosphate: This is an alternative control for slugs and snails not toxic to pets. Look for Sluggo or Bonide Slug Magic. Many others exist.