Hello,

If you are mulching for aesthetic purposes, you can determine the diameter of the mulch. This not only enhances the visual appeal of your garden.  If you are doing it to help keep moisture in the soil for tree health, you probably want to go out to the drip line.

Here is an article about watering and mulching trees:https://extension.umn.edu/planting-and-growing-guides/watering-established-trees-and-shrubs#benefits-of-mulching-1262611

To mulch mature trees, you should follow these guidelines:

**Clear any turf, weeds, or debris from around the tree's base to ensure the mulch is effective.

**Apply a 2-inch to 3-inch layer of mulch around the tree, ensuring that it does not accumulate more deeply than this to prevent water from being intercepted by the mulch.

** Mulch should extend at least to the tree's drip line, which is the outer edge of its canopy. Ideally, it should be mulched beyond that to cover the entire root system.

** Do not pile mulch against the tree's trunk, as this can hold moisture against the trunk and create a habitat for rodents.

If you have any further questions please don't hesitate to Ask Extension.