A hedge marks the boundary between one property and another. It creates privacy, blocks the wind and provides a natural alternative to fences. Hedges also serve as homes to wildlife, feeding birds and providing homes to birds, squirrels and other small animals. A hedge can consist of a row of trees, shrubs or a combination.
American arborvitae, also known as Thuja occidentalis, makes an excelling privacy tree. Maturing to a manageable height of 25 to 40 feet, this evergreen has a broad spread of 10 to 15 feet of dense branches covered with bright green needles. Its pyramidal shape keeps it dense near the base, ensuring excellent privacy screening. It also does well with shearing and training for gardeners who wish to shape their hedge trees.
With a spread of 20 to 30 feet of dense, bluish green foliage and a mature height of twice that, the Douglas fir (Pseudotsuga menziesii glauca) combines the privacy screening characteristics of a shrub with the majesty of a large evergreen. Douglas fir trees grow well in a variety of soil types and moisture conditions, making this tree an option on properties where poor soil and water would normally be an obstacle.
If you wish to combine the color and seasonal variation of a deciduous tree with the privacy of a hedge tree, the Washington hawthorne (Crataegus phaenopyrum) is a good choice. This dense, thorny specimen is nearly as wide as it is tall, with a maximum height of 30 feet and spread of 25. The foliage changes from reddish purple to scarlet in the fall, and the tree grows white flowers in the spring and red fruit later in the fall. The tree tolerates crowding well, and several can be grown 4 to 6 feet apart to create a dense hedge screen.