89% of soils contained residues of parent and transformed chlorotriazine herbicides. Topsoils are largely devoid of atrazine and simazine parent compound residues. Hydroxylated products are most abundant chlorotriazine residues (83% of soils). Low pH favors formation of atrazine, simazine and terbuthylazine hydroxy-residues. Banned triazines may enter soil as impurities of current terbuthylazine products.