Bt kurstaki (Bt-k)

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Monterey Bt (Bacillus thuringiensis) is a naturally occurring soil bacteria ideal for controlling cabbageworm, tent caterpillars, gypsy moth, tomato hornworm and other leaf eating caterpillars. Will NOT harm people, pets, birds, honeybees or beneficial insects. OMRI Listed for use in organic production.

Bt insecticide is most effective when applied to caterpillars during their 1st and 2nd instars, when they are still small. It must be ingested by the pest insect, as it is a stomach toxin.

Available size: Pint (16 oz)

Mix 1 to 1-1/2 Tbsp per gallon of water and apply when worms or caterpillars are first noticed, then repeat at five to seven day intervals while they are active. Apply thoroughly to top and bottom foliage. Reapply after heavy rains.

Active Ingredients:
Bacillus thuringiensis subspecies kurstaki strain SA-12 solids, spores and Lepidopteran active toxins (At least 6 million viable spores per mg) ….. 98.35%

Other Ingredients ….. 1.65%

Product Label – PDF
Material Safety Data Sheet (MSDS) – PDF

Grower’s Tip:
Bt-k biodegrades quickly in sunlight and may require reapplication under heavy insect pressure. To maximize effectiveness apply in the late afternoon.

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