underwood

Etymology
From.

Noun

 * 1) Underbrush, undergrowth.
 * 2) * 1670,, , London, Chapter 3, Of the Oak, pp. 16-17,
 * What improvement the stirring of the ground about the roots of Oaks is to the Trees I have already hinted; and yet in Copses where they stand warm, and so thickn’d with the under wood, as this culture cannot be practis’d, they prove in time to be goodly Trees.