How to Manage Pests

H   = high
M   = moderate
L    = low
—  = no information

¹

Rotate chemicals with a different mode-of-action Group number, and do not use products with the same mode-of-action Group number more than twice per season to help prevent the development of resistance.  For example, the organophosphates have a Group number of 1B; chemicals with a 1B Group number should be alternated with chemicals that have a Group number other than 1B. Mode of action Group numbers are assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at http://www.irac-online.org/.

²

Selectivity: Broad means it affects most groups of insects and mites; narrow means it affects only a few specific groups.

³

Generally, toxicites are to western predatory mite, Galendromus occidentalis.

⁴

Toxicities are averages of reported effects and should be used only as a general guide. Actual toxicity of a specific chemical depends on the species of predator or parasite, environmental conditions, and application rate.

⁵

Ratings are as follows: I-Do not apply to blooming plants; II-Apply only during late evening; III-Apply only during late evening, night, or early morning; and IV-Apply at any time with reasonable safety to bees. For more information, see How to Reduce Bee Poisoning From Pesticides (164K, PDF), Pacific Northwest Extension Publication PNW591.

⁶

Duration: Short means hours to days; moderate means days to 2 weeks; and long means many weeks or months.

⁷

If rate is less than 0.04 lb a.i./acre, rating is III; if 0.04 lb a.i./acre, rating is II; if 0.06 lb a.i./acre, rating is I.

⁸

If rate is 0.025 lb a.i./acre, rating is II.

Toxic against some natural enemies (predatory thrips, syrphid fly  and lacewing larvae, beetles) when sprayed and up to 5-7 days after, especially for syrphid fly larvae.

¹⁰ 

May cause increase in spider mite populations.