~ ~ ~ PURPOSE ~ ~ ~ this subroutine calculates degradation of pesticide in the soil and on the plants
calculate degradation in soil add decay to daughter pesticides calculate degradation on plant foliage adjust foliar pesticide for wash off BUG FIX: use += to accumulate foliar decay across plants add decay to daughter pesticides BUG FIX: use local metab_fol instead of accumulated hpestb_d%metab_f Previously, cs_pl was updated with the TOTAL accumulated metab_f, causing mass duplication for multi-plant HRUs