You probably know that Benlate has been the subject of many claims from greenhouse growers about phytotoxicity on various crops. The fallout from this controversy included DuPont's virtually eliminating ornamental uses from the Benlate label. Contrary to what you may have heard, however, certain conifer diseases remain on the Benlate label. These include Diplodia tip blight (on Austrian, red, and Scots pine) and Swiss needlecast (on Douglas fir). The fungicide is labeled for brown spot needle blight, but ONLY on longleaf pine, which doesn't occur in Iowa.
This article originally appeared in the June 30, 1993 issue, p. 109.