Note 7 — Pecans in Northern Virginia
Reading edition
I think the first phase of the suggested experiment has more to recommend it than the second. Perhaps the Round Hill tree gets needed zinc from clotheslines and roofing nails. A more scientific way to apply zinc is to use zinc sulfate in sprays or ground applications, and these are to be used on some trees at Urbana which Dr. Crane diagnosed as zinc-deficient.—J. C. McD.