The direct answer is: Broadleaf herbicides are not labeled for use on edible food crops and, therefore, the apples cannot be recommended for consumption. Remove all of the apples this year. This will prevent the tree from putting all of its energy into producing fruit and should prevent the alternate bearing pattern often observed with apple trees. A more detailed response: There are several different formulations of broadleaf herbicides, but the most common formulation contains MCPP (mecoprop) as the active ingredient. MCPP, according to the Extension Toxicology Network, has a soil residual activity of around two months. There is no information about the breakdown of MCPP in vegetation. MCPP is readily absorbed by leaves and roots, translocated through the xylem and phloem, and then accumulates in the growing points including roots, shoots, and fruits. There has been some research done on the toxilogical effects of MCPP. It has been found to have a low acute toxicity, but it has teratogenic and mutagenic effects at moderate and high doses, respectively. Carcinogenic effects are controversial, but MCPP has been shown to cause kidney damage in rats. Because the residual activity is relatively long, the chemical accumulates in growing tissues, and there are documented negative health effects.

Browse related Faqs by tag: horticulture, herbicides, fruit growing