Dangers of using pressure treated wood for hive stands

Posted in Bees on September 4th, 2013

Wes, W. a SABA club member, was having a terrible summer with his bees. The hives were aggressive and several of his queens were superseded. Due to his great record keeping, he was able to trace the problems back to his newly installed hive stands. These stands were build out of pressure treated wood and used with screened bottom board. He wrote a great email about what he learned.

I thought I would fill everyone in with an update to my dilemma earlier this summer.

Recall I was losing queens (absconding/death/swarming/drone laying) on a regular basis with no overt cause.

Aaron M. came by my yard a few weeks ago to try and help troubleshoot and he noticed the bees in the yard were “annoyed” even before we began to work them.

After his visit we could not arrive at any reason for the loss of queens/colony defensiveness other than the possibility below:

Ian M. (who learned this from Greg S.) suggested the queen problems might have something to do with pressure treated lumber. Apparently, pressure treated lumber is now using a different chemical (targeted as more of a pesticide than a preservative) and it is causing some issues with queens for some beekeepers.
Well, this spring, I just installed some new pressure-treated hive scale frames (they sit directly under my screen bottom board).

As I looked back over my notes from this season, I realized that all my problems began soon after I installed the pressure treated lumber under the colonies. I even saw a correlation between my lone overwintered hive that went “drone layer” in the spring; this happened 3 weeks after I installed the scale frame.

So, I removed the lumber from underneath the colonies and installed a virgin queen in my latest queenless hive.

I’m happy to report that all three of my remaining colonies are currently queen-right and doing well.

I share this story not only to fill everyone in that was following the thread, but as a cautionary tale about using “fresh” pressure treated lumber as hive stands. I can’t tell you how many hours and dollars this issue has caused me this year; for most of the season I felt like I was chasing my tail – running to and fro, replacing queen after queen. I believe it was all caused by my well-meaning installation of this hardware to help me quantify colony honey store rates.

Coincidentally, my actual hive stands are made from pressure-treated 4x4s, but they are at least 10 years old, and have been subjected to the weather for most of that time before I re-purposed them for hive stands.

Thanks to everyone who offered advice/queens/time to help me figure this one out!

I hope the next 6 months involve less drama for my colonies as I help them prepare their winter stores.


Purple Loosestrife

Posted in Bees, Photo Friday on August 21st, 2013

I know Purple Loosestrife is an invasive plant which is crowding into wetlands. However the bees just love it. Remember that honey bees are “invasive” to North America, so they tend to really do well on other invasive plants.



Move a bee hive, a little at a time

Posted in Bees, Photo Friday on August 16th, 2013

The hive looks like it could be bearding on a hot summer day. However it was actually caused by moving the hive about 16″ to the right. I am slowly walking this hive to a new location about 15′ away. Every few days, 30 to 60 minutes after I move the hive all the returning bees have clustered at the top entrance. A short while later all the bees have moved inside.