Thanks for your question.

I really can’t give you an unambiguous answer to your question. The primary reason for this is that it depends upon your specific time frame. The trees are still young. What may be acceptable to you now may not be acceptable to you some ten to fifteen years down the road. The good thing is that regardless of what you do for this 2026 season, it is not irreversible. You could always change things later.

Essentially you seem to be deciding between restoring the mulch or planting grass right up to the trunk. Here are my thoughts at this time (late March 2026):

1). Mulch does a great job in protecting the trunk and bark by keeping lawn mowers and string trimmers away.

2). Mulch does not consume water that may be needed by the roots.  Grass around the trunk eventually will compete with the tree for water and other soil nutrients. As this occurs it will be harder and harder for you to maintain a healthy turf under the trees.

3). Tree growth often causes a “lifting up” of their roots near the trunk. This causes no problems with mulch. You just add more to cover things up. If you add topsoil around the tree at this time to plant some grass, this may interfere with oxygen uptake by the roots. The roots will respond by more movement upwards. You will then have to add more topsoil. With time, you may end up with a high mound of grass surrounding the tree.

4). Currently the trees are young. As they grow, there will be increased shade under the branches. This will make it more and more difficult for grass to survive. Eventually you may end up with just bare ground under the trees.

5). I suspect that you may be leaning towards grass at this point for the appearance that this would create. It is certainly “neater” to have grass right up to the trunk than to see a ring of mulch. I agree with this feeling and at least for a few years, this “neat” appearance would be there. But what would things look like ten years hence when grass is unable to grow under the tree due to light and nutrient deficiencies? Growing grass under a growing tree is not a sustainable situation.

As I said you can’t make a wrong decision at this time. Just be prepared to change your mind if the situation changes. See the following for some additional opinions:

https://www.fs.usda.gov/nrs/pubs/jrnl/2016/nrs_2016_vansambeek_002.pdf?utm_source=chatgpt.com

https://extension.usu.edu/forestry/trees-cities-towns/tree-care/mulching-tree-health?utm_source=chatgpt.com

https://ctufc.org/news/turf-vs-tree-the-fight-for-light/?utm_source=chatgpt.com

https://extension.umn.edu/news/mulching-101-secret-healthy-and-happy-garden

https://extension.umn.edu/news/mulching-and-perennial-overwintering

Good luck. Please get back to us if you have additional questions. Thanks for consulting with us.