Pruning RedBud Trees a Huge Challenge

Question: Pruning RedBud Trees a Huge Challenge

Dear Maryland CES:
I planted 20 American Redbud tree seedlings about 6 years ago.
They are all from seed s of a single tree in Southern Delaware (except for 2 which I bought at Home Depot). 
I have pruned them to permit grass cutting around them and for facial safety.
I have lost three from huge splits or insect boring.
Some are becoming top-heavy or awkward in appearance.
The parent tree must have bad  genes.
The Home Depot RedBuds aren't plagued with splitting and top-heavy problems.
I didn't expect this kind of problem when I planted these trees from Delaware; I've successfully pruned other trees such as maples, American Black Cherry.
My question is: how do I prune them?
Better yet, do any of you live in Elkton; maybe you could visit and guide me and Suzanne.
Would have been nice to upload more photos for you (only 3 allowed).
Best Regards,
Stephen

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 June 26, 2024, 12:51 PM EDT
response: Hello Stephen,  Seed genetics is not likely a factor in this case. Tree branching responds to many factors (only some of which are genetic), including environmental conditions like sun exposure, prevailing winds, and so forth. Nursery-grown trees are often heavily pruned over the few years they spend being cultivated at the nursery before they are sold, and do not always reflect the natural branching structure a tree of the same age growing wild would have. (Ironically, sometimes that natural form would be better, though not always.)  Redbuds do not maintain a central leader the way other species can, like oak. Pruning practices for Redbud won't be much different than that for other trees, which relates to the usual aspects of branch-to-branch spacing, crotch angles (how narrowly or widely a branch is connected to the trunk), branches growing into the canopy instead of away from it (or growing too close to each other vertically), and so forth.  Limbing-up trees, which is the practice of removing lower branches, can slow the process of trunk thickening and taper development in young trees. This is because the food made by the leaves on those lower branches helps the trunk widen to better support the tree overall. Although you've already done this, we recommend not continuing the practice. Plus, as trees age, those lowermost branches are temporary branches anyway, which will eventually die off on many cases on their own, so they are not permanent within the canopy.  Instead, when trees are surrounded by or near lawn, the grass should be removed for some distance out from the trunk, and the soil protected with mulch (or perennial plants, if desired) instead. This distancing not only reduces root competition between the tree and the turf, but also helps shield the trunk from accidental mower or weed-whacker strikes (which can be serious or fatal for a tree and are not treatable), plus any use of lawn herbicides that might hit the bark. We think we see some evidence of bark damage to one of the trees pictured, right at the level a mower or other equipment would be hitting it with the grass growing right up to the trunk. This barrier will also negate the need to remove lower branches that might be getting in the way of a mower.  We don't have extensive pruning guidance on our UMD web pages since most gardeners plant trees already shaped initially by the nursery supplying it, but other Extension pages go into more detail. We'll share one example from Univ. of Florida about formative tree pruning, and a video series by Iowa State Univ. that includes how to prune trees in the right location on the branch to avoid trunk wood decay. You can also hire a certified arborist to assess the trees, make recommendations, and either perform the pruning or to teach you what to look for and how (and where) to make the cuts.  Miri

responder: The Question Asker Replied July 03, 2024, 3:05 PM EDT
response: Miri:Thanks for your redbud tree advice. I'm a slow learner, but I will refrain from pruning them any more. I didn't realize that these lower branches were temporary and were needed to strengthen the trunk - interesting. You all are very knowledgeable and have many years of experience. Best Regards, Steve    On Wed, Jun 26, 2024 at 12:51 PM Ask Extension <<personal data hidden>> wrote:

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 July 03, 2024, 5:10 PM EDT
response: Thank you, and you're welcome.