Checking Tree Roots

Checking Tree Roots

The Basics
“When woody plants decline or die, assess the root system’s health. Suspect a root injury or disorder when an entire plant declines or dies. Digging out or around newly planted woody plants makes it possible to evaluate their root systems. For older established plants, root health can be evaluated by digging small holes or slices, or by inserting a soil probe in several locations at various distances from the base of the plant. It is usually necessary to explore about 1 to 2 feet deep, since most of the root system will be present in this zone. Look for numerous fine roots (1/10 in in diameter) that are firm and entirely white or white inside with a dark outer cover. If very few fine roots are found or if they are soft, rotten, and brown, the root system may not be vigorous and healthy enough to support the plant.”

Excerpt From the California Master Gardener Handbook, Dennis R. Pittenger

Checking for Root Rot
This YouTube video shows how to look for signs of root root, including oak root fungus (Armillaria) and Phytophthora. 
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