How to Build a Decorative Cement Tree
- 1). Dig a hole for the concrete tree. Make the hole's diameter slightly larger than the desired diameter of the tree trunk. Dig the hole 40 inches deep. Compact the bottom of the hole by tamping it with the butt of a scrap 2-inch by 4-inch board. Fill the hole with 4 to 6 inches of gravel. Tamp the gravel.
- 2). Use 1/2-inch diameter rebar with a length a little more than three times the desired height of the tree trunk. Fold the length of rebar into thirds. To bend, insert the rebar into a rebar bender and apply force on the protruding end.
- 3). Fill the hole with wet concrete to create a footing. Insert the thrice-folded piece of rebar into the center of the wet concrete.
- 4). Build the tree armature. Create the "bones" of the tree trunk and off-shooting branches with 1-inch-by-2-inch boards. Wire the trunk board to the rebar, with the end of the board submerged a few inches in the concrete footing next to the submerged rebar. Tack the branch boards to the trunk board with stainless nails or screws. Avoid creating a huge canopy on the tree, as that may make it overly top-heavy.
- 5). Wrap sections of flexible wire mesh around the boards to create the cylindrical forms of the trunk and branch. Embed the bottom end of the wire mesh trunk into the concrete footing, around the perimeter and about 1 inch in from the edge of the hole in the ground.
- 6). Coat the wire mesh with spray-on insulating foam. After the foam dries, shave the bumps down with a hot wire cutter, a sharp knife, a fine-blade hacksaw or a surform.
- 7). Add water to a normal concrete mixture to create a slightly soupier mix. Cover the tree form with a layer of burlap strips dipped in the concrete. Cover the burlap layer with a 1/2- to 1-inch-thick layer of concrete. Spread the concrete onto the form with a trowel.
- 8). Allow the concrete to set slightly and run the corner of a putty knife blade up and down the concrete in short, successive strokes to mimic the texture of bark.
- 9). Cover the tree loosely with plastic. Leave the plastic on to hold in moisture for three days while the concrete cures. Periodically spray the tree with a fine mist of water.
- 10
Paint the tree with a coat of clear concrete sealer once the concrete has fully cured.
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