Captain Richard has a nice photo tutorial on making realistic looking brick walls from paper. Teh key is torn and overlapping prints of brick texture paper.
Modeling
Making Large Removable Canopy Stands Of Trees
For areas of particularly dense forests, creating large tree bases with removable canopies allows you to properly hide your figures.
Making A Desert / Wasteland Terrain Cloth
The 1000 Foot General has a tutorial on making a desert / wasteland terrain cloth.
Making A Hedge Maze For Your Miniatures
Storm The Castle has a photo tutorial on making a hedge maze. I’ve been doing a lot of looking at hedge construction techniques as I prepare for my own hedge row project.