Redbud fungus

Question: Can anyone tell me what this fungus is on my eastern redbud.

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied October 03, 2024, 5:21 PM EDT
response: It's hard to tell from such a close-up image, but if it's fungal growth emerging directly from the wood/bark (as it appears to be), then it's not a good sign and suggests that wood decay is taking place (and has been for some time). Wood decay can either be more passive, with fungi rotting wood that had already died from other causes, or it can be active, with the fungus causing the wood death itself as it consumes the tissues. From the appearance of the mushroom itself, sometimes it's hard to tell which is which since some fungi look alike. Neither can be treated.  If located on a branch, that branch can be pruned off, but if it is growing out of the trunk, nothing can be done (it can't be excised or treated with a fungicide). Sometimes trees have means of walling-off areas of decay within the wood itself (this would not be visible from the outside), preventing it from worsening even if the dead area becomes hollow, but that process doesn't always work, and then decay progresses to the point of killing the canopy. Worst-case, if the roots are otherwise healthy, the tree could be cut down if the canopy dies and you could wait for suckers (new stems) to emerge from the roots or stump, allowing one or several to mature into new trunks over time.  Depending on the age of the tree, it's not uncommon for age-related decline to impact Redbuds around 20-30 or more years of age, since they naturally do not live as long as oaks and some other species.  Miri

responder: The Question Asker Replied October 04, 2024, 8:02 AM EDT
response: Thank you Miri. This has been ongoing and kept at bay by one very expensive root treatment. The tree is 25 years old. If I take it down, would I need to also remove the roots and all the surrounding soil in order to replant at the same spot. It's a feature tree in my front yard.   Regards, Janet

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied October 04, 2024, 10:07 AM EDT
response: With regards to a risk of fungal spread, no, you probably do not need to remove the old tree's remnants in order to replant, since most fungi that cause wood decay actively rely on weakened, stressed, or injured plants to invade the wood, and young and presumably healthy and vigorous new tree won't be very vulnerable. However, if the stump and old roots are physically in the way of digging the right size of planting hole (only as deep as the new root ball, but at least 2-3 times as wide), then they should come out for that reason. The soil itself does not need removal, and there are plenty of beneficial microbes in soil along with the handful of very common pathogens (that could recolonize new soil at any point even if sanitization efforts were successful or practical) that you don't want to disrupt if possible.  Miri