As the managed honey bee industry continues to grapple with significant annual colony losses, the Varroa destructor mite is emerging as the leading culprit. And, it turns out, the very nature of modern beekeeping may be giving the parasite the exact conditions it needs to spread nearly beyond control. In an article published yesterday in […]
For Varroa mite control, I sprung for a ProVap110 this year. I put it through the paces this week and thought I’d report on it here.
View Video Here: https://youtu.be/yYl63Akou3E
Disclaimer first: Yes, Larry of OxaVap is a friend of mine. We met at a South Carolina Beekeepers Association conference several years ago and hit it off talking bees non stop for the duration of the conference. This was all before oxalic acid was approved for use in the United States. Larry told me then it would be the next big deal in Varroa mite control and apparently he was right as it was approved a couple years later. (Larry also told me where U.S. beekeepers were already ordering vaporizers from across the border in Canada.) Anyway, Larry and I always look forward to conferences and hanging out, telling bee stories when we can.
Before getting the ProVap110 I was using two Varrox, pan type ,vaporizers. Using two really sped up my mite treatments. Duh, twice as fast, right? No, don’t ask me how but everything moved faster and down time between hives was less so I really think I was doing the job in less than half the time than with one.
Recently, Larry suggested I needed to try the ProVap110 but I was resistant due to the issue of needing AC current. He said that most inexpensive car/truck inverters would do the job as it only used 250 watts and 2.2 amps. I checked and Harbor Freight had an inexpensive inverter. But I really wanted to be able to treat without having to drive my truck into sometimes muddy out yards. Larry assured me that a long extension cord run would not be a problem but I resisted and bought a small WEN 1800watt generator. I do plan on buying that inverter as well but the WEN1800w is under 50 pounds and, so far, I really like it and don’t have to worry about getting my truck stuck in a muddy out yard field while vaporizing mites.
One morning this week I oxalic acid vaporized 32 hives in about an hour and 15 minutes. As with the old Varrox, you still have the setup time of placing IPM boards under screened bottom boards to help seal the hive as well as a damp dishcloth across the entrance. I left the WEN1800w generator in the back of my truck and used a 50 ft extension cord. The extension cord had no noticeable effect on the operation as the ProVap performed exactly as the enclosed paperwork stated it would. I will use a 100 ft extension next time to see if that has any effect. The ProVap110 took about 2 to 3 minutes to reach its operating temperature of 230C. The unit adjusts to maintain that temperature throughout its use. I’ll place a link to a video in this post for those who have not seen how it operates. Basically, after it reaches its operating temperature a measured amount of OA is placed in a cup and attached to the ProVap110 while inverted. The nozzle is inserted into a 1/4″ predrilled hole in the hive body and the unit is spun around to its upright position causing the OA to drop into the 230C pan. The temperature readout dropped to approximately 208C when the OA came in contact with the heating unit and immediately began its rise back to 230C. Within about 20 seconds the temperature had returned to 230C and I removed the unit from the hive. An additional “cup” is provided so the user can prepare the dose for the next hive during the 20 second wait. And so it goes hopscotching down the row of hives.
Some things I learned are: 1) Hole placement is more critical than I first expected. I had used a homemade template based on the instruction sheet and some of the holes were drilled into handholds which caused me to have to hold the unit in place instead of leaving it to prep the next dose. The instructions say drill the hole 3 to 4 inches up from the bottom . I will drill future holes either above or below the handholds in the lower box – if you use cleats drill above or well below. 2) The tube that sends the vapor into the hive is copper and about 3/4″ in length. That makes sense since it is going into a hive body with a thickness of 3/4″. Longer and it could bottom out on a frame inside. It makes sense but I’d like the tube to be made of a harder metal than copper if possible – I am uncomfortable with the possibility of bending the copper tubing. 3) You will need an acid/vapor PPE mask as you will be in close proximity of the OA vapor. There is no getting around this. I currently use a 3M 7502 mask with organic vapor/ acid gas filters – $13.99 on Ebay, and non vented safety goggles – $7.99 Ebay. The mask worked great and I never even got a whiff while standing behind the hive administering the OA vapor. (more on this later)
Some of the nice things about the unit are: 1) Its speed. I usually just stood there behind the hive for 20 seconds and let it do its thing. 2) The plume of vapor into the hive is thick and sudden. The bees don’t have the “warning time” they did with pan type vaporizers to start fanning. Bang, it’s in there and done. Most of the hives didn’t object any more than they did with the pan vaporizer but a couple did. All hives settled down soon afterwards. 3) The almost constant 230C temperature ensures the OA is properly sublimated. I always suspected the gradual warming of the OA with the pan vaporizers may have wasted some of the OA as it was evaporated, boiled off, or was otherwise consumed instead of sublimated thus diminishing the dose. The ProVap110 ensures the OA always hits the pan at exactly 230C. 4) I often lose my biggest and strongest hives over the winter. I’ve always suspected it might be related to inadequate OA treatment reaching the upper boxes. Now I can treat the hive via a 1/4″ hole placed anywhere, in any box, instead of just underneath the hive. And don’t worry about drilling 1/4″ holes in your woodenware, the bees will propolize it soon enough or you can use a golf tee or dowel rod to plug. 5) It would be nice to have a half dozen of the “caps.” to prepare in advance. It’s not essential; that’s just my OCD speaking.
General comments: Most efficient use would necessitate a planned layout of the hives in the bee yard. If you scatter your hives around here and there you’ll waste time in transit. I have basically three different zones in my home yard. This meant driving the truck to three different positions and repositioning the drop cord each time. I think keeping your hives within a 100 foot radius and using a 100 foot drop cord might be ideal. Having plenty of IPM boards available is also a great time saver as transferring them hive to hive is a time waster. Luckily I have plenty to use in case of a severe winter but others may not. The hives with solid bottom boards were easiest to treat.
Now, here’s an interesting thing: The visible escaping particulate using the ProVap110 was noticeably less than when using pan type vaporizers. I can’t really account for why this is other than the bees don’t have the 2 – 4 minutes to start fanning before the deed is done. I actually used the ProVap110 in the first two hives and thought, “Did it work?” So I loaded the ProVap110, held it downwind, and flipped it to see if it was sublimating the OA. Yes, it was working and it’s done in about 20 seconds. If you look at the video, at the end the guy does exactly this and you can see how thick the plume is and how fast it comes out. Anyway, my point is, there appears to be less particulate escaping the hive than with pan vaporizers – and that’s a good thing!
Cleanup is a breeze. A little water to wash out the areas where the OA comes in contact was quick and easy. The unit itself cools off quickly when unplugged which is good and bad. Good for safety once you are done but moving into different bee yard zones meant having to wait the 2 – 3 minutes for the unit to return to operating temperature. I’m convinced I can shave 30 minutes off my first effort implementing some of the changes mentioned above.
I am satisfied with the unit over the pan type vaporizers for a few reasons: time efficiency, proper sublimation, flexibility in selecting placement of the area the OA is administered, and ease of use. I’d recommend it to anyone that starts to feel that pan-type vaporizing is taking too much of their bee management time that could be better spent more productively.