4-Amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylic acid (halauxifen) or 4-amino-3-chloro-5-fluoro-6-(4-chloro-2-fluoro-3-methoxyphenyl)pyridine-2-carboxylic acid or agriculturally acceptable esters or salts of either are used for selective pre-emergence and post-emergence control of undesirable vegetation in the presence of vine crops such as grapes and other perennial crops.4-胺基-3-氯-6-(4-氯-2-氟-3-甲氧基苯基)吡啶-2-羧酸(哈洛昔芬)或4-胺基-3-氯-5-氟-6-(4-氯-2-氟-3-甲氧基苯基)吡啶-2-羧酸或是任一者之農業上可接受的酯類或鹽類,係使用在像是葡萄之藤蔓作物和其他多年生作物存在下,用於選擇性萌芽前及萌芽後控制非所欲的植被。