dense

Entry Definition
(in forest) the trees are so close together that it is hard to see or walk between them; it is a thicket, there is a thicket
there is thick woody growth, there is dense brush (too thick to walk through)
very close together, touching or almost touching (said of group of many objects; e.g., trees, vines, clouds, chairs, people)
(tree) s/he is densely branched
(tree) h/ grain is dense or solid, h/ wood is hard to split