Any gardener who’s been around the block a few times has probably used the insecticide Sevin®, known generically as carbaryl. First introduced to the public in 1956, carbaryl was the first commercially successful product in the carbamate insecticide class. Since then, it has been a pest control workhorse for vegetable gardeners and fruit growers. It’s relatively low cost, broad spectrum activity, and relatively short (usually 3-day) interval between application and harvest made carbaryl a popular choice for growers. Its relatively low oral and skin toxicity to mammals also made carbaryl a favorite treatment choice for on-pet use against fleas.
In recent years, newer, more powerful pyrethroid insecticides have come to dominate store shelves, making carbaryl harder to find. A few years ago the Sevin® trade name was purchased by the pesticide distributor GardenTech. This year, GardenTech is switching the active ingredient in Sevin® Insect Killer from carbaryl to zeta-cypermethrin, a newer pyrethroid insecticide.
According to one industry rep, GardenTech “upgraded” the active ingredient in most Sevin® products to zeta-cypermethrin this year. Sevin® Insect Killer Lawn Granules are changing their active ingredient to bifenthrin + zeta-cypermethrin. The Sevin® Ready-to-Use 5% Dust is not changing immediately. It is still carbaryl, though this may also change.
Manufacturers commonly change ingredients in brand name products; however I can’t recall a similar name change in an insecticide active ingredient so closely tied to a trade name as carbaryl and Sevin®. It will be hard for me to disassociate myself from thinking of Sevin® as anything other than carbaryl. It is something akin to changing the active ingredient in Tylenol® to something other than acetaminophen.
So if you expect to be getting carbaryl the next time you go to the store, look carefully at the label. If it’s a GardenTech product you may be getting a different active ingredient than what you expected. That’s not to say the change will be bad. Zeta-cypermethrin and bifenthrin are both excellent active ingredients with longer staying power than the old carbaryl. In some, if not most, cases, it will likely perform better than carbaryl. But for some pests it may not.
To verify the active ingredient in Sevin® or any other insecticide, look in the list of active ingredients at the bottom of the front label. You should see a generic active ingredient name followed by its percent content in the product by weight. This is one of the first things I look for when shopping for a pesticide. It’s a wise gardener who knows what they’re spraying on their plants. For more information, see our fact sheet on Understanding Common House and Garden Insecticides.