So the people went out into the field against Israel
Josephus F5 calls it a great field, with a wood behind it:
and the battle was in the wood of Ephraim;
or near it F6 rather; not in a wood in the tribe of Ephraim, which lay on this side Jordan; whereas this battle was fought on the other side Jordan, in the land of Gilead, not far from Mahanaim, where was this wood; and which was so called, either from the slaughter of the Ephraimites here in the times of Jephthah, ( Judges 12:4-6 ) ; or from the Ephraimites feeding their cattle here and near it; for the Jews say F7, that Joshua gave them a grant to feed their cattle in any wood in any of the tribes of Israel; and lying near Jordan, they used to drive their cattle over to this place, from whence it had its name.
F5 Ut supra, (Antiqu. l. 7. c. 10.) sect. 2.
F6 (reyb) "ad sylvam", Junius & Tremellius; "prope sylvam", Piscator.
F7 In Jarchi, Kimchi, & Abarbinel, in loc.