Remove all the rocks, shrubs and grass around your tree. Use a garden rake to loosen the soil around the tree, being careful to not damage or stress the tree roots. Use spray paint and measuring tape to mark the area around the tree that the bench will be accommodating.
Circle the tree with the bender board using stakes in the ground to hold the bender board in place. Follow the outline of your spray paint. Use a shovel and dig out about 2 inches of dirt from inside the bender board and then level out the ground.
Place landscaping fabric in the wrap-around tree bench area then secure it down with pins. Cover with crushed rock then compact it down with a hand tamper. This prevents weeds from coming through the bench but still allows water to get to the tree roots.
Build skids to support the wrap around tree bench without harming the roots of the tree. Use pressure-treated lumber and construct skids that are 16.5 by 15 inches. Use a miter saw and make 45 degree angles then secure the wood together with two 2 1/2-inch woods screws.
Construct the wrap around tree bench in an octagonal shape. The smallest piece of wood, or the piece closest to the tree, will be 14.5 inches long, the middle piece 19 inches long and the outer piece 28 inches long. Cut eight of each size. The wood needs to have a 22.5-degree angle at each end.
Secure the 3 graduated pieces of wood together using a 1-by-2 inch board across the backside to make a seat panel. Secure the seat panel to the middle of the skid using deck screws. Work all the way around the tree making sure that the skids line up before securing them together.
Make a fascia on the front of the wrap around tree bench to close it up and make it more attractive. Build this using 2-by-6 redwood planks.