Arborvitae trees, known for their dense foliage, are popular choices for privacy screens, hedges, and landscape accents. For these trees to thrive after planting, understanding the root ball is important. Its size and condition significantly influence the tree’s health and ability to establish in a new environment.
Understanding Arborvitae Root Balls
An arborvitae root ball is the contained mass of soil and roots attached to the tree when it is dug for transplanting. This unit is essential for the tree’s survival outside its original growing location. The root ball minimizes the stress a tree experiences during relocation, often called transplant shock.
Maintaining an intact and healthy root ball is important for the tree’s long-term health. The roots within this ball absorb water and nutrients. A compromised root ball can hinder these functions, leading to poor establishment or decline. The structural integrity of the root ball ensures that the delicate feeder roots remain undisturbed and functional.
Standard Root Ball Dimensions
Determining the appropriate root ball size for an arborvitae is based on industry standards, related to the tree’s height or trunk caliper (diameter). The American National Standards Institute (ANSI) provides guidelines for minimum root ball sizes for field-grown trees. A common rule suggests a root ball diameter of at least 10 to 12 inches for every inch of trunk caliper. For example, a tree with a 3-inch trunk caliper requires a root ball with a minimum diameter of 30 to 36 inches.
Trunk caliper is measured 6 inches above the ground for trees up to 4 inches in diameter, and 12 inches above ground for larger trees. Root ball depth is also important, recommended to be about 70% of the ball’s diameter. Nurseries adhere to these specifications to ensure the tree has adequate root support. When selecting an arborvitae, visually inspect the root ball; it should appear firm and tight.
Ensuring Planting Success with Proper Root Balls
Careful handling of the root ball is important to prevent damage that can sever feeder roots. Before purchasing, examine the root ball for signs of damage or if it appears undersized for the tree’s height and caliper. A loose root ball indicates roots have separated from the soil, stressing the tree. The topmost root emerging from the trunk should be within two inches of the root ball’s surface.
When planting, the hole’s depth should match the root ball’s height, ensuring the top is level with or slightly above the surrounding ground. Planting too deeply can lead to root rot, while planting too shallowly may prevent establishment. The hole should be dug approximately twice as wide as the root ball for root expansion. After positioning the tree, backfill and water thoroughly to settle the soil and eliminate air pockets.