boron from wood ash

If one uses wood ash around the orchard, would this not make adding borax redundant or even counterproductive due to possibly overly high levels of boron? Is there a boron test?

Some wood ash has negible boron ... and some wood ash contains significant boron. As in 1-3 or more lbs. of actual boron per ton. Playing it safe is where the recommendation to limit wood ash application to 20 lbs. per 1,000 sq. ft. per year comes from. But then again there may little boron in those ashes. I expect a soil lab could analyze this each time, and you could start to make assumptons as to hardwood/softwood, rainy year/dry year, and whatever other variables contribute here. Keeping tabs on boron every few years with a test of orchard ground is best ... whatever your source of boron. I typically use Borax detergent (11.3% actual boron) sprinkling it like fairy dust to meet the ppm test recommendations.

Lost Nation Orchard
Zone 4b in New Hampshire

I agree with Michael, it is only redundant if you know for certain that the wood ash in question has a good boron content to it.

I was recently at a field day at UC Davis and the discussion turned to the high boron content in the well water around the campus, itself, and surrounding farms. Many growers see boron toxicity often and regularly test for its presence in the soil and in tissue analysis.

A&L Western Labs offers a soil test specifically for Boron for a mere $8 here is a link to see that test as well as dozens of others

If you really want to test your wood ash for boron (and any other trace minerals) call a reputable soil lab and ask them what they suggest. Might be relatively easy to do. If you do it, post up the results to our forum. Would be an interesting reaad

You may have a good Ag soil testing option locally, including some universities, that can do exactly the same thing.

Good luck

Gopher Hill Apples
Zone 8 in California