Herbicidal and plant growth-regulating pyridiyloxy-phenoxyalkanecarboxylic acid derivatives of the formula ##STR1## wherein A is cyano or carboxyl, an ester, thioester or amido radical or the salt of the carboxylic acid with a cation or a quaternary ammonium group,Z is hydrogen, halogen, cyano, nitro, C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy,D is hydrogen, halogen, cyano, nitro or C.sub.1 -C.sub.4 alkoxy,E is halogen, trifluoromethyl or cyano.R.sub.1 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.2 -C.sub.8 alkoxyalkyl or C.sub.1 -C.sub.5 alkoxy carbonyl andR.sub.2 is hydrogen or C.sub.1 -C.sub.4 alkyl.