[spoiler]I think I'll go with Overgrowth unless someone complains very loudly, very soon. It'll be a semi-circle (150ft radius) with the flat end against the edge of the forest. Theoretical middle of the flat end will be at J13, but I'll leave a square with the corners G13, M13, G10, M10 unnafected. Since there is no larger trees out there I assume ranged weapons will still be able to hit them since it seems the stuff will grow roughly to their chests.[/spoiler]
A smile spreads across my face as I finish the last syllable of the spell. When the last of the built-up energy leaves me I say to the squirrels and their mounts Now they won't be able to move just as much, and you badgers will be able to take them down one by one as they exit.