The Scofield Bible Commentary, by Cyrus Ingerson Scofield, , at sacred-texts.com
Groves, like high places, have been associated with idolatrous worship from time immemorial. The Hebrew, asherah, translated, grove means also the idol enshrined there. (Deu 16:21). This idol seems often to have been a sacred tree, the figure of which is constantly found on Assyrian monuments. In apostate Israel, however, such groves were associated with every form of idolatry, for example (Kg2 17:16); (Kg2 17:17),
(See Scofield) - (Kg1 3:2)
(See Scofield) - (Jdg 2:13).