Sue,
I agree, with just one quibble: these "%"s are are not needed. Just a typo, right?
WAS:
and then x 1000 gives 0.11% to 0.23% of a lb. of borax per 1,000 sq. ft.
Should be:
and then x 1000 gives 0.11 to 0.23 of a lb. of borax per 1,000 sq. ft.
P.S. That was a great link. Note this:
"There is also a very narrow range between boron deficiency and toxicity
as more than 5.0 ppm available boron can be toxic to many agronomic crops."
As with many kinds of chemical fertilizer, "too much" is much worse than "not enough".
If someone is adding Boron without a soil test, I would urge them to add only to one small square, and only add a fraction of the total tolerable boron. Like 1/4 or 1/2 ounce per 1,000 sq. ft. Keep adding that much each year until you either see improvement (boron deficiency) or toxicity.
Then decide how much to add to the rest of your yard. "Less is better", because you can always add more next year.
But you can't go back next year and "take away" some that you already added.
1.8 oz to 3.7 oz = 52 to 104 grams / 1,000 sq. feet
I would dissolve borax in water and then spray the soil, if I were trying to add that little of something uniformly, to avoid toxic spots.
