Growth of a Root Rotting Mushroom
October 2002 (revised September 2010)
(At the bottom of this page are some updates from 2003)
For years I have been observing and wondering about the cinnamon-brown mushrooms (really basidiocarps) that grow at the base of our willow oaks. During that time it was identified as "white root rot" ( later I learned that it is often referred to as Weeping Conk)which is not a very scientific way to describe it. From the standpoint of one in the tree business, I knew that when I saw the fruiting body or mushroom that there would be extensive root decay below ground and out of sight. When asked about the damage done, I often used the analogy of the newly planted apple tree that requires four or five years before it has fruit, and by that time the apple tree has an extensive canopy.
This year, 2002, with the recent rains and the previous severe four-year drought, for some reason of nature, we have seem numerous incidents of root rot. In some cases, the mushrooms have been entirely around the base of the tree; in some it just appears to be starting.
In my own back yard for the first time I noticed a small basidiocarp (reproductive body) at the base of one of our willow oaks. I have taken a series of photos of it as it grew in size. The tree in question is a willow oak about 80 feet high with a circumference of 150 inches. ( We removed this tree in April of 2007)
Here are a series of pictures. Click on the booth and see the larger photo. I have observed both the
Inonotus dryadeus and the Ganoderma lucidum frequently here in Charlotte.
The Inonotus dryadeus appears to be the most common on our willow oaks and like other similar decay fungi enters the tree through wounds. Once you see the fruiting body there is not much you can do. The presence of a single conk or mushroom does not mean that the tree needs to be removed, but as the mushroom appears more often around the trunk then you need to consider removal soon. If the mushroom is visible all the way around the tree than it definitely is a hazard tree and should be removed immediately. As a note, I have seen trees that look healthy some seven years after first seeing the basidiocarp. I know of one water oak (Quercus negra) that is still alive some 20 years after I first saw mushrooms on it. Since we have had such an unusual bloom of mushrooms this year, I paid a visit to the water oak and it was still very much alive and I saw no evidence of the mushroom, but the trunk was knurly. I have some photos of this water oak if someone wishes to see them.
Photos from NCSU web site
Photos above are from NCSU web site.
October 13, 2003
Mushrooms are late this year. I have seen some today October 13, 2003
December 22, 2003
December has been pretty normal. Fortunately, we have not had a severe ice storm as we did last December 5th. There is still a lot of evidence of storm damage in many trees from that storm. I also think that our trees are under a tremendous amount of stress. Prior to five years ago, we rarely saw the large mushrooms at the base of the willow oaks. Now they are very common, and it would be interesting to make a survey of willow oaks impacted by streets or residential structures. It would include streets, sidewalks, patios, curbs, driveways in the term structures.
When the roots are wounded, this creates openings for aggressive fungi. Four years of drought also has stressed the trees, and I personally believe that drought, ice damage, excessive rain early this spring all stress the trees and that is why we are seeing more fungi.
I have a large willow oak in my backyard that in 2002 developed a mushroom (Inonotus dryadeus) on one of the flare roots that protrudes into the gravel driveway. I first noticed it when it was about the size of a silver dollar. By the end of the fall, it was about a foot in diameter. In 2003 it did not appear at all, and that in itself was interesting to me since I thought it would be larger and more spread out in 2003. Past experience shows that once this fungi starts growing, it gets progressively bigger each year. I will be posting some additional photos here.
We took this tree down in the spring 2007 shortly before I sold my company. I had the stump removed, and because it sat on such a knoll, we had to clean up all the stump cuttings and dirt just so we could see the remaining roots. Finally in the spring of 2010 we had a second shot at the stump removal. Finally it is done and I have raked it out and reseeded. I reseeded the area the last of August and today is the 25th of September 2010. The photo below shows what the status of the lawn is now. The ground is soft and the grass very tender. We have had over 85 days in the 90’s and it has not rained since very early September so the yards are very dry. Our water bill will be high.
September 25 2010
I have seen the Inonotus root rot mushroom on only one tree so far. That is a white oak on Queens Road at a private residence..
In my own yard on one of my favorite trees displayed the fungus a year ago. (2009) This year so far there are not new mushrooms visible but below is a photo of the left over mushrooms from last season. When I first saw the mushroom in the fall, it took up just about 15 inches of circumference around the base of the tree. As the season progressed, it spread and the current measurement is ????? (I never got around to measuring this, and now the tree is gone)
I will photograph the tree with mushroom in early October. 2010. (I have done this just not loaded it yet)