Mark off root protection zones around each tree. These areas should be as large as possible, but, for example, a tree with a 6-inch-wide trunk should have a protected circle 12 feet across. If possible, include several trees in a larger protection area. Surround the zones with sturdy, highly visible fencing to make sure the protected area is not breached, and spread mulch over the soil within it. Water the trees deeply before construction begins.
