Worldwide Beekeeping

Beekeeping => Pests and Diseases => Topic started by: Mikey N.C. on August 21, 2019, 06:23:54 pm

Title: BT , powder ?
Post by: Mikey N.C. on August 21, 2019, 06:23:54 pm
Is it true you can't buy BT powder for mix with water in spray bottles, for wax moth on drawn combs ?
Title: Re: BT , powder ?
Post by: iddee on August 21, 2019, 08:44:06 pm
Yes, it is true, but you can buy it to spray for cabbage loopers legally.
I never did like cabbage loopers in my hives, did you?   :o   :D
Title: Re: BT , powder ?
Post by: tecumseh on August 23, 2019, 06:52:47 am
it use to be marketed as Certan for wax moth and bees.  To my understanding it was only registered in Canada.  Based on articles in the Abs 40 years ago it was about 95% effective.  Basically the larvae have to eat the stuff to kill them so you may see some small amount of wax moth damage.

You have to be certain to get the right strain of Bt since each stain is made for a certain type of moth larvae.
Title: Re: BT , powder ?
Post by: RAST on August 23, 2019, 10:50:49 am
What I used to use. https://www.forestrydistributing.com/xentari-df-biological-insecticide-omri-listed-valent
Title: Re: BT , powder ?
Post by: Bakersdozen on December 02, 2020, 11:01:58 am
I thought I would refresh this thread.  I see that Certan is available again in the US, except for CA, NJ, and HI.  Mann Lake has a 5 oz bottle available.  Does anyone know how many supers that will treat?
Title: Re: BT , powder ?
Post by: RAST on December 02, 2020, 06:35:01 pm
That's gonna make 3 qts. I used about 8 ozs mixed last week doing 1 7&5/8 8 frame box with a small hand sprayer. I'll let you do the math. I am curious what they use to hold the BT in suspension for liquid shelf life, you have to use what you mix w/water and dump the rest.  2 days later it stinks in the bottle, trust me.
Title: Re: BT , powder ?
Post by: Bakersdozen on December 03, 2020, 11:17:55 am
That's gonna make 3 qts. I used about 8 ozs mixed last week doing 1 7&5/8 8 frame box with a small hand sprayer. I'll let you do the math. I am curious what they use to hold the BT in suspension for liquid shelf life, you have to use what you mix w/water and dump the rest.  2 days later it stinks in the bottle, trust me.
   
       https://www.vita-europe.com/beehealth/products/b401/#store (https://www.vita-europe.com/beehealth/products/b401/#store)
"Once diluted, the solution must be used the same day. Before mixing, calculate the amount of product required to treat the desired number of frames."
I couldn't find the answer to your question but confirmation about dumping what you don't use that day.
Title: Re: BT , powder ?
Post by: Gypsi on December 24, 2020, 11:45:53 am
I refrigerated the stuff I got in about 2012 and it did seem to work the last time I used it, which was probably 2016.  I don't have a lot of wax moth trouble, since I freeze my frames and cycle out and melt the old comb. . Guessing might be time for new stuff?
Title: Re: BT , powder ?
Post by: rober on December 25, 2020, 11:15:04 am
i'm reviving this again. BT was approved in the U.S. for beekeeping. approvals need to be renewed periodically. the producers decided they were not selling enough BT to beekeepers to justify the cost of renewing the approval. there are various strains of BT that are used for different pests. the version that works for wax moths is Xentari. the manufacturer of Dipel says it is only partially effective with wax moths. i bought some dipel to experiment with on hive beetle larva. it did not work. once xentari is mixed with water it has a 48 hour shelf life. also the powder itself has a shelf life of one year. i've found that if i do not cross stack boxes & run a fan on them for a few days after treating the frames will mold so i spray frames just before putting them on the hives. also- the treatment only last for a year or two so it needs to be reapplied at least every 2 years.
https://www.7springsfarm.com/xentari-bt-df-1-lb-bag/
Title: Re: BT , powder ?
Post by: Bakersdozen on December 26, 2020, 10:42:54 am
Wax moths are attracted to brood frames, but will destroy honey super combs as well.  The adult moths are attracted to bee larvae cocoons and feces.  I can see the value in treating supers, dead outs, and frames used for swarm lures.  I have been using Paradichlorobenzene, but am still concerned about it's toxicity to humans and bees even though it is approved.  I don't have a specific reason to be concerned, just that it smells like moth balls and dissipates like moth balls. 
The bee lab at the University of Iowa uses a different method for controlling wax moths in stored frames and boxes. No treatment is used for controlling wax moths.  They store all their equipment along a wall with spacing in between.  Each box is slanted downward, at about a 45 degree angle, allowing lots of sunlight and artificial light in each box.  Being a University, they have a lot more available resources and space than most of us.