What to do this week
By Mark Govan, Host “Florida Gardening” on 970WFLA Live on Sunday’s 7-9am
Mushroom Root Rot and what you need to identify this problem and tips on how to avoid it.
Mushroom root rot or Armillaria is a deadly disease that kills trees and shrubs by attacking their root systems. Once this disease enters the root system of a vulnerable plant, decay begins. By the time you notice the warning signs, I will go over below, your plant may be lost. Even shrubs or trees near an infected plant could be at risk of loss. In this article, I will go over the most obvious symptoms you should be scouting for in your landscape. You will also learn how to help prevent this problem from establishing a foothold and what you need to do once you find out your plants have been affected. This disease works quickly, so let’s get started.
Late fall and early winter are great times to start scouting your landscape for the above-ground symptoms of this disease, mushrooms. These mushrooms are very distinctive in the fact that they grow in large clusters (ten to twenty) of light tan to yellow colored mushrooms, which all emanate from a single point or stipe. These mushrooms normally grow from the base of the infected plant or root system but sometimes may even appear several feet away. You may notice many such clusters covering large areas. Do not be surprised to see these clusters growing upon dead stumps of fallen trees or even living trees, which may not show any outward appearance of being infected. These mushrooms are said to be edible. However, some people have shown to have had adverse reactions to eating them. Seek guidance from a professional grower before eating any mushrooms.
Other symptoms you may not think to look for, which are attributed to this disease are an overall decline of the plants. Dead branches scattered throughout a seemingly healthy plant or dieback of the plant or hedge starting from the top of the plant or tree could also be attributed to this problem. Eventually, death of the plant may occur even though other plants of the same species directly next to the diseased plant remain in good shape. I have personally seen fifteen-foot cedar trees die while another tree, not five feet away will survive. Even large hedgerows may lose several sections, while the rest of the plants remains healthy.
If you suspect a tree or shrub may have this disease, and you have no outward signs of infection, then you can dig down to the root system or scrape the bark from the base of the tree. This is where the “roots” of this disease does its damage, directly under the bark. Mycelial fungus destroys the water and nutrient carrying ability of the root system rendering the roots incapable of sustaining the tree causing its eventual death. Once you scrape the bark away you may see the white mats of the mycelia. Bark on smaller roots may even slip off leaving the mycelial behind when pulled upon. Once a tree has reached this level of infection, death is very near. Plants of the same species in close proximity of the diseased plants could already be infected and should be removed to slow the spread of the disease. Plants of another species could be replanted in this area and should be relatively safe from infection.
The only real way to protect your plants from being stricken with this disease is to maintain your plants by spraying for insect populations, foliar diseases, and adding nutritional supplements regularly. This means you will need to provide the proper care your plants need by being proactive. Fertilize your plants with a good-quality fertilizer every other month. Spray your plants with a fungicide and insecticide every two months or as needed. Inspect your plants regularly to make sure they are healthy or hire a professional applicator to maintain them for you. Prune your trees and shrubs to promote good growth and irrigate your plants when they are dry. During periods of high heat, check your plants more regularly. Plant a diverse landscape with as many varieties of plants and trees as you can tolerate. Make sure the plants you have chosen will all grow in our climate zone. Using the right plant in the right place can help you grow a better landscape.
Enjoy your garden and the plants that make you happy. Inspect them regularly and seek out the advice of professionals when you see a problem. Learn as much as you can about the plants you grow and remember, without plants, we would not be here!