Poplar trees are relatively easy to transplant. Young, small trees should be uprooted in early spring just after the ground has thawed. When replanting the poplar, choose a location that is as similar to the original as possible. This way (as long as the roots are kept moist and undamaged), the poplar will find it easy to adjust to its new home and will establish itself quickly.
Dig the Poplar
Take a sharp spade and prune the roots one year before transplanting. Do this in a circle around the tree that is 1 foot in diameter for every inch of diameter of the tree's trunk. Dig just as deep as the radius of the circle. This is best done in early spring just after the ground thaws. If your plant is large, prune one side in early spring and the other in late fall (after the leaves have fallen but well before the first frost).
Water the soil around the poplar thoroughly three days before you plan to transplant the tree.
Tie up any low-hanging branches on the day of the transplant to prevent injury or breakage during the move.
Mark the side of the trunk that faces the sun. Replant the tree so that its orientation to the sun is the same.
Dig out a root ball 12 inches wider in diameter than the pruning in step 1, using a sharp spade. If the poplar tree is large, you may have to dig a trench around it to access the bottom of the root ball. Be sure that all of the tree's roots are severed before you move it.
Spread out a piece of wet burlap large enough to completely cover the tree's root ball.
Remove the tree from the hole and place it in the center of the wet piece of burlap. Then wrap the burlap around the root ball. Tie it closed with rope or string.
Prepare the planting site. Dig a hole three times wider than the poplar tree's root ball and just as deep. Then fill the hole with water and allow it to drain.
Unwrap the poplar tree's root ball and check its roots. If any of them are damaged, kinked or circling, cut them with sterilized pruning shears.
Plant the poplar in its new location. It should be at the same depth and orientation to the sun that it was in in its previous location.
Water the soil thoroughly, but do not flood it. Continue to keep the soil moist to a depth of 4 inches until the tree is established and producing new growth.
Spread a 4-inch layer of organic mulch around the tree as wide as its drip line. Keep the mulch at least 5 inches away from the base of the tree.