SavATree - Tree Shrub and Lawn Care

What’s Happening in Your Neck of the Woods?

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Cotton Root Rot

This destructive soil-borne fungus is native to the southwest, and attacks more than 2000 different plant species, including ornamental plants and fruit, nut and shade trees. It kills the plant’s root tissue, then uses the dead tissue for food.

How can I tell if my plant is affected?

The leaves of an infected plant will turn yellow or bronze, then wilt. The plant will die quickly after these first symptoms—within a week—but the wilted leaves will remain attached firmly to the branches. (Large trees and shrubs may take a bit longer to succumb.) Sadly, by the time you see the leaf-wilt, the root system has been thoroughly overrun by the fungus. Wet conditions can create sporemats—ranging from two to 16 inches wide—on the surface of the soil. The mats will first appear white and cottony, and then turn tan and powdery.

What can I do to prevent the spread of cotton root rot?

By employing a multi-pronged management plan, your arborist can save infected plants and prevent the spread to healthy ones. A good management plan may include: fertilizing and applying soil amendments, monitoring irrigation, incorporating organic matter into the soil, vertical mulching, applying a layer of wood chip mulch over the root zone, careful and selective pruning, and the introduction of resistant plant varieties as barriers between infected and non-infected plants.

Phytophthora Root Rot

Though once considered a fungus, Phytophthora is now classified as an oomycete, which is more closely related to algae.

How can I tell if my plant is affected?

Plants will appear drought-stressed no matter how well you water them. The leaves may appear dull, or turn to autumn-like yellows/reds/purples long before fall sets in. Unlike cotton root rot, this disease is typically slower-progressing. While some plants will die during the first warm spell after infection, others can limp along for years.

What can I do to prevent the spread of phytophthora root rot?

An infected tree or shrub can sometimes be saved by clearing soil away from its base, cutting away diseased bark, and leaving the root system to dry out completely. Needless to say, you should leave this to professionals.

Contact your SavATree arborist at the first sign of these destructive pathogens, so an appropriate prevention and management plan can be put in place on your property.

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