The Barrington Hills Observer

The loss of a large shade tree will increase the amount of sun for your garden. | Jeff Carrion/Chicago Botanic Garden

By Tim Johnson | For the Chicago Tribune

I have two large shade trees that are not leafing out. Does that mean they are dead and need to be removed? What should I consider when organizing the removal of the two trees?

— Carmen Rios, Vernon Hills

If the dead trees do not pose any safety hazards and their appearance in your garden is not an issue, you may want to wait until winter or late fall to remove the trees to lessen the impact on your garden. You may also be able to secure better pricing if the work is done in the winter. The more plants around the trees that are to be removed, the more difficult it will be for a company to complete the removal. Between the crew walking around to perform the work and branches that fall on your garden, there’s a higher risk of trampling on perennials if the work is done during the growing season. However, I have seen tree removals done during the summer with remarkably little impact on surrounding plants. Most perennials will recover and look good next year but it may spoil the appearance of a portion of the garden for the remainder of the gardening season. Perennials like hosta are easy to move out of the way for tree work and replace when the work is completed. You do not describe where the tree is located on your property, but access for large equipment will also be a factor in removing it. Putting plywood down before driving in large equipment and avoiding work when the ground is wet is best practice. There will be less soil compaction if the ground is dry or frozen when the work is done.

If you decide to grind the stump, shrubs, ground covers and perennials within a foot or so of the stumps will likely be destroyed or damaged when the stumps are ground out, so you may want to temporarily relocate them. If the stump is 2 feet or more in diameter, clear a space 2 to 3 feet away from the stump. Have the stump ground to at least 12 inches in depth if you want to plant new perennials in the same location. The more soil depth the better for the new perennials. New trees and shrubs with a large root ball will need to be planted adjacent to the old stump and you will need to cut through old roots from the tree while planting. A sharp axe works well for cutting out larger roots.

The grinding process will leave a large mound of chips mixed with soil that will need to be removed and replaced with topsoil. Be sure to remove the wood chip and soil mix down to the bottom of the hole left by the grinding process. If you plan to have the stumps ground out this winter, transplant any valuable perennials and shrubs next to the trunk of the tree this fall in preparation for removal of the tree stumps this winter. The stump grindings can be piled up in the back corner of the yard to decompose over a couple of years. This will leave you with topsoil to reuse in your garden.

The loss of a large shade tree will increase the amount of sun for your garden, and this will affect the performance of existing plants. If there are other adjacent trees that provide shade for the beds, the impact will be less. Think about the need to relocate plants that may end up being in too much sun next year and replace them with more sun-loving plants. Trees and shrubs in gardens grow over time and gradually increase shade. As light decreases over time, some plants can start to struggle, and when a tree is removed the light levels return to better levels for the plants. If you are unsure of the impact the tree removal will have, look carefully at how the plants respond to this change in your garden over the growing season and adjust their locations if you see problems with too much sun.

For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org. Tim Johnson is senior director of horticulture at the Chicago Botanic Garden.