"Sevin" shelf life ??????

[Hanover Bill]

I have a container of powder Sevin for mite control, and it has been very effective when used in moderation. I purchased it a couple of years ago, and since you use so little of it each season it is still almost full.

Question is, would it still be effective or does it lose it's clout over time? I hate to discard an almost full container if not necessary, but I also want to be sure I am getting maximum protection.

Hanover Bill.

[Craig Dyer]

Hi Bill,
My experience has been that sevin dust loses it's effectiveness a few months after opening. It seems to biodegrade quickly once exposed to the air and moisture. I buy a fresh container each spring, as it is relatively inexpensive. I suppose if you keep it well sealed it would last longer.
Craig

[ToyinPA]

Bill:

I've been using the same container for a couple plus years with no problems. No mites at all. Mine is the tall container with the yellow plastic snap tight lid.

My husband is out shoveling the snow away from the martin houses right now. We got hit pretty hard here in February, so he's got a couple feet of snow to move, with ice on top. We will take the covers off & get the nest trays loaded this week.

The martins seem to be marching north fast. Earliest they have arrived at my site was March 23rd. I'll be ready this week for them....I have lots of hand warmers, crickets & a warm nest .

I just hope we don't have another cold wet summer like last year.

Toy in PA

[jr 2]

I have the same container that toyinpa has that I bought last year but I went an bought a new container this year;;;;it is not real expensive;;;don't no for sure about the shelf life and I did not find a date on what I bought but I have used over half of it on my 50 compartments as I will have my houses ready and waiting this week;;think my first arrival last year was around april 1st;;;;;jr2

[Emil Pampell-Tx]

How long it lasts will depend in part on how you store it. If you store it in a dry room, it will last for many years. If you store it in a damp shed outside, it should still last for the 2nd year. Most people rather buy a small container than take a chance on it being bad. Martins require a lot of time, so we sure do not want to add to the work with a mite problem.

[Craig Dyer]

I was curious so I did a little research on the shelf life of the insecticide carbaryl (the main ingredient in sevin). There has been extensive research and study done on this insecticide. I did not find a definitive answer regarding it's shelf life, however, as Emil suggests storage is key. Shelf life can be extended by storing it in the original air tight container, in a dry and cool location. It breaks down more quickly if stored in temperatures above 100 degrees F. I had been storing mine in a non air-conditioned shop.

Some insecticide manufacturers recommend buying just enough product to last for one season. Thus eliminating safety, shelf life, and storage concerns.

[Hanover Bill]

Thanks for all of the good responses. It is appreciated.

Hanover Bill.