[Food Storage - Pests] Me v. Indian Flour moth

julianj

Indian Flour Moth – A Nasty Pest

I have had an infestation of a pest called the Indian Flour (or Meal, or Pantry) Moth in my kitchen. I am posting this to warn others of the possible problems – particularly if you are like me and are storing lots of dry goods.

Some of me admires the ingenuity of this creature’s lifestyle, but it has been a real pain to get rid of it.

Last year I noticed I had some small (1 cm long) passive brown moths, which just sit on your walls – not the active flapping-round-lights kind. So I let them be.

A big mistake.

Once they started turning up in my kitchen cupboard, I became more worried and nuked them with my electric flyzapper – a satisfactory outcome.

I had noticed some sort of cobwebs in a packet of oats, which were nearly finished so I just threw them away.

As the weather grew colder no more moths appeared so I did not give it any interest.

Like many POers I have a lot of dry goods stored, and I also often would pick up rice, noodles, flour, oats, etc if I saw a packet on special to add to my hoard. Unopened packets are easier to store by squashing them together than putting them in glass or plastic containers, especially as my kitchen is tiny. I also mill my own wheat and make my own bread, so my place is like flour moth Disneyland.

This year the moths are back. Last year's eggs must have hatched when the weather got warmer. They kept turning up in my cupboard. I started to realise I had a problem of pest infestation. Not having any interest in entymology I wasn’t clear about their life cycle until I started researching it.

What happens is the adults don’t eat, procreate, then the female lays lots of miniscule eggs (almost invisible to naked eye) in or near your dry goods, and the larvae can chomp their way into unopened packets or cardboard boxes, including quite tough plastic bags. There they eat the food, cocoon themselves in the webby stuff I mentioned earlier, and then emerge as adults, who only live about 14 days (or 14 minutes in my cupboard!)

If you find the cobwebs or grubs, throwing the goods out is just passing the problem on to someone else. What you need to do is put the goods into the freezer for 5 days to kill the larvae and eggs. After that you can throw them away, or alternatively just scrape away the top layer of the flour, and continue to use it.

The moths’ larvae only need a tiny amount of dry goods to live on. Basically no matter how clean your kitchen is, they can find something to eat – and mine must have a layer of flour dust behind every appliance because of the milling.

I’ve cleaned the kitchen till I’m blue in the face. Moving all the appliances and removing – ahem – a lot of ancient dirt.

Unfortunately the eggs can be in nooks and crannies, which you will find every kitchen and store-room has.

I obviously don’t want to put insecticide into cupboards where I’m going to store food. I did try to clean with a germicidal household cleaner.

Still there has been a new moth there for the last few days. Somewhere they must be hatching.

Fortunately I remembered my steam cleaner, and steamed every crevice in the cupboard and all around the kitchen as well as under all appliances. This seems to have worked.

My advice is – if you see one of these moths, go all-out to eliminate them immediately.

You can get pheromone traps which capture the males so the females don’t breed. I don’t know how effective they are. Freezing dry goods (temporarily) and steaming are the methods I recommend.

More info:
http://organicgardensite.com/bugs-harmful/flour-moths/

Cashmere · Light Sweet Crude Joined: Mar 27, 2008 Posts: 1449

Interesting.

Thanks.

Question - What do the new hatchlings use for water?

If they come out of minuscule eggs, then they need water to grow, regardless of the availability of food, I would think.

Is it possible they're getting enough water from flour? Wow, that would be a tenacious bug.
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julianj

Sorry Cashmere, I haven't a clue.

But believe me, they are fine however they are if they have dry goods.

Fishman

Essentially water independent. These bastards are tough. Problems in some of my stored rice recently. My wife has moved everything they can eat into large tuperware like containers. Limits the spread some. I know the freezer kills the adults, not sure if it kills the eggs.

Cashmere · Light Sweet Crude Joined: Mar 27, 2008 Posts: 1449

No water required?

Unbelievable!

Mylar, Plastic, Zero O2 baby!
_________________
Massive Human Dieoff must occur as a result of Peak Oil. Many more than half will die. It will occur everywhere, including where you live. If you fail to recognize this, then your odds of living move toward the "going to die" group.

katnipkid · Tar Sands Joined: May 30, 2007 Posts: 36

I had this problem with grain moths. The pherome traps work, but they will take a little time to be effective. Don't give up on them. I freeze my flour and grain products for a full 2 to 3 weeks. The spice cabinet never,ever had a problem with them, I was told bay leaves were the answer. There are so many spices in the cabinet I can't say for sure. When I did the master gardener course I had time to read up on the various moths. Apparently there is one that goes after spices, too! I never had any trouble with spices, as I said earlier. Any food placed in the spice cabinet ended up having a weird multi spice taste, even if it was sealed in a container. The moths are difficult to get rid of, as they live also on paper it seems. I found imported pastas and flours to be the worst source of them. Hope this info helps.

julianj

How interesting.

I have some packets of spices in with the flour - they didn't seem to be infested at all.

Nor did the dried mushrooms.

Thanks for the suggestion about freezing longer - it isn't going to do any harm, and I think I might adopt it as Standard Operating Procedure, before I store my stuff in future. There's been no activity from things I have taken out of the freezer so I am pretty confident it has killed the eggs.