carpenter bees below wood deck

To whom it may concern …

My carpenter bee problem exists below my untreated wood deck. The homes they’ve created are not the floor boards, but rather the joists underneath the floor.

Although the deck is 16′ x 20′, I feel they are ” only ” inhabiting 10% of the total area. To access their nests they are squeezing thru the 1/4″ to 3/8″ gap between boards. As the crawlspace under the deck is minimal, I’ve only been on the attack from the top of the deck floor using a white, foam spray that does an exceptional job as they try to squeeze back into their homes.

My problem is I  really have no way to get to their 1/2″ bored holes w/o ripping out 6 or 7 floor boards. I am concerned as in 4-days of the ongoing battle I’ve killed 45 to 50 of the varmints, and there still is activity.

If I use the CYPERMETHERIN, I’ll only get it between the floorboard cracks and maybe a small portion on the face of the floor joists. Will this minimum contact with the CYPERMETHRIN low down their activity, or possibly even be fatal?

Thanks in advance for your thoughts.

Getting the dust into their holes is usually important for long term control as explained in our CARPENTER BEE CONTROL ARTICLE. That being said, it’s not going to be a practical option in your situation. But there are two things you can try.

First, if the space between the deck planks are fairly tight, the bees are likely to touch them as they crawl in and out from underneath. A good dusting with DRIONE will get dust up under the deck planks. It’s a light dust and will fly around coating the exposed wood surfaces quite well even without a direct treatment. Just trace amounts landing on the wood underside can have a profound impact since it takes little Drione to impact the bees. In fact, if you blow enough down into the space, some will travel up into their nests as well. That means as the bees fly down and crawl into their hidden nests, they’ll pick up small amounts of dust and die.  I suggest treating once a week till you don’t see any activity. This has proven to be quite effective in all the cases I’ve tried it given the way Drione floats around and adheres to surfaces. I also suspect because it’s so active on bees there is a good chance you can get them even when you only get them with a small amount of product.

Additionally, liquid spraying with CYPERMETHRIN every month there after will also help prevent future infestations. The scent of treatments done throughout the summer months will deter any bee or wasp from wanting to make a nest and will effectively keep them away for long term control. I suggest you broadcast it over the areas where you see them coming and going. Do this first, before the dusting with Drione, and then let the spray dry. Afterwards you can dust so effectively you’ll have Cypermethrin on the top side and Drione on the bottom side.

Direct links to these products and information can be seen here:

Carpenter Bee Control:  https://www.carpenterbees.com/carpenter-bee-control

Drione Dust:  https://www.bugspraycart.com/insecticide/dust/drione-dust

Cypermethrin:  https://www.bugspraycart.com/insecticide/liquid/viper-cypermethrin

jonathan

www.bugspray.com