Take a second to picture a tree that you love – maybe it’s the big oak in your backyard, the street tree in front of your house, or the new ornamental tree that you just planted in your garden. You probably will do (a number of things²) several things to care for your tree – water it while it’s young or during a period of drought, mulch it in the springtime, or get it professionally pruned as it matures.
You might also do some things to mitigate harm to the above-ground portions of the tree, like ask a builder not to hit the trunk or branches during a home renovation project. However, we generally don’t consider the potentially harmful effects of our every-day behavior on the health of our beloved trees, and consequently, fail to implement a few simple, but high-impact solutions.
Interacting with Our Trees
Let’s take those three hypothetical trees mentioned above. Maybe you picnic around that big oak in your backyard or dash underneath the canopy when it starts to rain. Maybe you walk across the sidewalk tree well in which your street tree is planted, while being careful not to hit the trunk as you open your car door. Maybe you water your ornamental tree, and then walk about the garden pulling weeds and tending to other plants.
These are all wonderful ways to interact with the trees at home or in our communities but walking repeatedly across the soil that’s covering tree roots (particularly when the soil is wet) is not one of them³. This causes the soil to compact, squeezing out of it the water and oxygen essential for healthy plant growth.
Water is an obvious plant requirement, but oxygen is just as necessary below ground as it is above. Without soil oxygen, the tree’s vascular systems cannot properly function and roots are unable to absorb water. There also are microbes and organisms underground that are beneficial to tree survival and need oxygen as well.
Spike Aeration Boosts Tree Health
Here at RI Tree Council, we (definitely) don’t want you to stop picnicking under your tree or wandering around your garden – and the good news is, you don’t have to! Here are some tips (and tricks) to perform soil aeration (the practice of loosening soil to create pathways between soil particles) so that you can keep your beloved trees healthy for years to come.
Spike aeration is the easiest way for home gardeners to aerate their soil on their own! Grab a spikey tool, like a hand cultivator, metal rake, or pitchfork and puncture the soil in a broad area all around your tree. This will allow it to become more porous so oxygen can access the roots and water can drain more readily through the soil. Be careful not to stab surface roots with your tool!
Aerate around your trees once or twice a year, in the spring and/or fall, and always follow-up with mulch (find a great video on how to properly mulch HERE). For mature trees that are starting to show their age, it might be best to aerate the soil, mulch a large area around the base, and then try your best to walk over the roots as little as possible. Mature trees tend to be even more vulnerable to soil compaction.
Lastly – be aware that a healthy-looking tree is not an indication that your soil is fine! The negative impacts of soil compaction might not become visible in the canopy for (a number of growing seasons) many years. Be proactive and build aeration into your annual tree care routine.
Want more tips about keeping your trees healthy, or planning for the installation of new woody plants? Check out RI Tree Council’s other articles on tree care HERE, or sign up for the next Tree Stewards course!
