Redbud tree leaves turning brown
Hope you're doing well. I have a 7-year-old redbud tree that, so far, has been doing well and it's planted in a shaded area in my backyard. When the extreme temperatures hit several weeks ago and high temperatures consistently in the 90s or more, about 70% of the leaves turned brown and looks like they're about to fall off and similar to what usually happens in November. There are some green leaves left, but it's pretty dramatic. I assume this is due to the high temperatures? I've tried to water the tree, but, at this point, it seems like the leave are so brown they'll just fall off. I probably should have watered the tree more and didn't get around to it everyday. Do you think my tree will survive? I've attached a photo and some of the leaves still appear to be green. Thanks!
It's possible that the redbud is dying from drought, which dies up and kills roots. We see that it has some very surface roots, which suggests that the soil is hard or poor below. In that case, water deeply through fall (many droughts extend into fall.)
It could also be a disease, Botryosphaeria, which you can't treat. It is associated with drought. It will die eventually.
In any case, prune out totally dead branches. To determine whether a branch is dead, scratch the bark and look for green tissue underneath. Green indicates it is still alive.
You may want to see how it goes next spring. If it has lost too much of its canopy, replace it.
Last August, you answered a question I had about our redbud tree, and I really appreciate your help. I watered the tree quite a bit last fall and hope it will be okay this spring. I've attached a couple recent photos and wondering if I should place soil/dirt around the base of the tree to cover the exposed roots? (In your response last August, you mentioned that the exposed roots could indicate poor soil quality.) Would placing soil at the base of the tree help? Would fertilizer help? I'm just trying to see if there is anything I can do to save this tree. Thanks! Steve
The surface roots appear to be fine with regards to depth. Roots are quite sensitive to changes in grade (i.e., burying them in extra soil) and so covering them with more soil (enough that it would remain covered as opposed to a sprinkling that would erode away again) would likely be detrimental to their health. Tree roots can grow more shallowly when soils are compacted as they are trying to stay in the zone of soil with decent oxygen penetration. Improving compacted soils in an area with established roots is challenging and best addressed during new plantings instead. The key with more mature plantings such as this is to maintain good plant health by minimizing stress - watering well only when necessary, avoiding wounding (from lawn equipment, deer "buck rub", etc), and not over-fertilizing. While you may not have deer in this yard due to the fencing, the Redbud does appear to be surrounded (mostly) by lawn, so take care with mowers and string trimmers so the bark isn't damaged. Opportunistic, incurable diseases can move into a tree in such cases. Mature plants also rarely need fertilizer as our soils tend to have sufficient quantities of most if not all important nutrients. You could have a soil test done this winter to see if any corrections need to be made this coming spring. If the Redbud leaves hadn't shown signs of deficiency last year, it is unlikely that any fertilizer will need to be used. Information on soil testing and a link to area labs can be found here: https://extension.umd.edu/hgic/topics/soil-testing.
Thanks Miri! I really appreciate your help and advice!