Trees produce extensive root systems that spread out and down from the base of the stump. These roots can remain active for long periods of time, causing the stump to produce new shoots with green foliage for several years after you cut down the tree.he exact amount of time it takes a stump to decay varies depending on the species of tree and the conditions in your yard. If you do not want to wait, there are ways you can encourage a stump to break down on your schedule instead of nature's.
1 Materials and installation for a stone retaining wall start around $25-$40 a square face foot and go up depending on materials, site conditions, and other factors. 2  It costs $1,250-$2,000 or more for a wall 30 inches high and 20 feet long.
Retaining Wall Cost. Poured retaining walls with elaborate curves require complex formwork and will drive up cost for a wall. The total cost to have a concrete retaining wall installed will be a combination of material and labor prices. For a basic wall you can expect to pay between $30 and $40 per square foot.If you add a decorative finish, curves, steps, lighting or other upgrades, the cost will rise.he total cost to have a concrete retaining wall installed will be a combination of material and labor prices. For a basic wall you can expect to pay between $30 and $40 per square foot.