Maple removal/replacement

Question: Even before the lanternflies moved in, my maple trees have been showing signs of crown decline. These were planted by the city in our yard as part of a new development. I'd like to replace them with serviceberry or another smaller native that won't be an issue with the sidewalk or foundation at full size. What do I need in terms of permits/process?

responder: Answered by theHome 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 September 23, 2024, 12:32 PM EDT
response: Good news on the spotted lanternfly: they are not hurting trees or plants other than grapes and black walnut seedlings. They will be a nuisance insect for a time but we expect their numbers will sharply decline as they have in the counties where they first arrived in large numbers.  The maple trees actually look o.k., especially for newly planted ones given the intense and prolonged heat and drought that we have experienced this year. Has anyone been watering them?  In terms of process or permits, you would have to contact your county government for that information, though we'd be surprised if they would be willing to replace them at this point.  If you do keep them, monitoring them and watering when needed is crucial for the entire 18-24 months of establishment. Here's our watering page: https://extension.umd.edu/resource/watering-trees-and-shrubs/ And they definitely need some mulch and perhaps soil removed. You should be able to see a widening or flare at the base of the tree before it goes into the ground.  A trunk that goes straight into the soil/mulch like a telephone pole is one that will eventually weaken over time.  More on mulching here:  https://extension.umd.edu/resource/mulching-trees-and-shrubs/   Christine

responder: The Question Asker Replied September 23, 2024, 5:43 PM EDT
response: Thanks, Christine.  Great to hear on the lanternflies! The trees were planted in 2021, so they're past the 24 month mark. The one has had the signs of crown decline for over a year with increasing die back. I have pulled back some of the mulch multiple times - the neighborhood landscapers are terrible at volcanoes - and can certainly pull back some more! I wasn't sure when to know to stop? Also, should I prune back the dead sections? Thanks, Jenny On Mon, Sep 23, 2024, 12:32 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 September 24, 2024, 9:53 AM EDT
response: Hello Jenny,  To know when to stop uncovering the trunk base of a tree, you'd look for the root flare. This is the location where major roots branch off from the trunk, and it's not uncommon for landscapers to install trees too deeply, or for nursery-grown trees to be buried too deeply in their pots or root ball by the time they are sold. More information can be found on the two linked pages. You might find that the root flare is several inches too deep, covered by mulch and probably also soil; it's an unfortunately common occurrence.  Prune off leafless branch tips that have died any time, though the sooner the better so their potential breakage in a storm doesn't cause further damage to healthy wood. Although the branches in question might not be too large, you can find pruning guidance on our Pruning Trees web page, which includes a diagram and video demo link for where to make the pruning cut when branches join each other (or the trunk), to avoid cutting too flush with the live wood. When out of reach from the ground, a pole pruner tool can be useful so you don't have to work around a ladder.  If either maple succumbs in the future and you wanted to replace it with a Serviceberry (or another species) at that point, locate the new tree's trunk(s) far enough back from the sidewalk so that the eventual branch spread won't impinge too much on the walkway where they would need pruning, since it's always best to limit the removal of healthy tree wood unless absolutely necessary. There's a range of potential widths for mature Serviceberry (and Redbud, Dogwood, and most other small trees), but a general guideline would be to expect at least about 8 feet of branch reach out from the trunk in any given direction when the tree is mature, so the trunk should sit about that distance from the edge of the sidewalk, if you have room.  Miri

responder: The Question Asker Replied September 25, 2024, 3:32 PM EDT
response: Thanks! This is also my concern about the maples (and was expressed by some neighbors when they were first planted) They are only 3 ft from the sidewalk and 22 ft from the house (closer than that to my patio and the neighbors foundations). I'm expecting them to damage the sidewalks at a minimum at maturity and potentially damage the foundation or other underground utilities.  On Tue, Sep 24, 2024, 9:53 AM 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 September 25, 2024, 3:44 PM EDT
response: We doubt they would damage a foundation or bother utility lines (other than potentially being in the way of easy access if lines need to be dug up in the future for a repair/replacement), but defer to an experienced, certified arborist. Maples do have relatively shallow roots that might buckle sidewalk blocks in a couple decades, as they age and roots enlarge in girth. Regardless of tree species, just about any roots will grow more shallowly in compacted, oxygen-poor soils, but maple roots generally start out more shallow than most naturally. (Magnolia, birch, and beech also tend to do this.) Still, when they have the option of more space in another direction, tree roots tend to grow wherever they have the most resources (moisture, nutrients, oxygen, space to grow), so trees close-ish to the sidewalk in this situation, where they have more of a yard to meander in, should be better-off and less likely to buckle sidewalk than, say, a similar tree wedged into a "hellstrip" space in D.C., with pavement over much more of the root system, which forces them to stay shallow and expand in what little free soil they have access to.  Miri