Mixing Borate to Control Post Beetles

Advice on obtaining and mixing borate pest-control formulas. January 8, 2010

How much Boric Acid do I mix with water to kill the beetle?

Forum Responses
(Sawing and Drying Forum)
From contributor D:
I'll stick to the home chemistry part of the question. If you want to use boric acid it takes borax and boric acid combined to make DOT, the borate you want. The U.S. Navy spec. is 60% borax-40% boric acid (this ratio gives the maximum solubility of borates in water). To make this solution mix 65% water, 20% borax, 15% boric acid and heat until dissolved. I don't do it that way myself, I like the easy way. I buy 50 lb sacks of Solubor and mix at a rate of 1 lb/gallon of water for a 10% solution. At 1.5 lb/gallon itís a 15% saturated solution that is stronger but will crystallize overnight so it must be used up when you mix it and clean up any spray equipment really well.

From the original questioner:
Thank you for the info but where do you find the Solubor? I tried the farm store but no luck.

From Gene Wengert, forum technical advisor:
Try asking the store for borate preservatives, as there are several trade names, including Timbor.

From contributor D:
It will need to be a farm supply that farmers go to, probably not a suburban type store. It may need to be ordered from their chemical supplier but will be in their catalog. Solubor is a boron soil amendment used here by tomato, pepper and cole crop growers although it is used for many crops. It comes from US Borax as does Timbor. The prices I've seen for Timbor are several times the price for Solubor as it is a "listed" chemical. They are both chemically identical, disodium octaborate tetrahydrate.

From contributor S:
Solubor is used around here by apple orchards as a foliar spray to help improve bud development and fruit set. The composition of Solubor and Timbor look the same to me but the Borax website has all the details of these products.