No, we don’t mean literally. However, there are ways to allow your trees to “stretch their legs,” so to speak.
Tree roots need oxygen in order to spread and grow. Unfortunately, city soil is often very compacted due to foot traffic, vehicle traffic, and construction. This compaction limits the movement of not only oxygen through the soil, but water as well. Water is needed for nutrient transfer to the tree, and it is essential to the process of photosynthesis. Oxygen is required for nutrient absorption to the tree. Without it the roots, and by extension the tree, will die.
We can allow our roots to get some fresh air by easing the soil compaction around our trees. We do this using a compressed air tool to aerate the soil and allow that oxygen to get in to the roots.
We can use a radial trenching technique, where we make trenches in a spoke-like shape throughout the root zone. We then backfill the trenches using a nutrient-ric custom compost mix.
Example of radial trenching
Alternatively, we can do a vertical mulching technique, where we create columns in the soil around the tree’s root zone and fill those back up with our custom compost. Both of thee techniques create pockets of oxygen throughout the root zone, and also get helpful organic materials back into the soil.
Vertical Mulching w/ Custom Compost
Soil Aeration Tubes
Another way we can give our roots some room to breathe is by installing aeration tubes. These tubes about about 18” long and 4” in diameter with a plastic or metal cap. We install them by creating a column with the air spade around the root zone of the tree, similar to our vertical mulching technique. Then we insert the tube into the column, with the cap of the tube resting right at grade. The walls of the tube are permeable, so oxygen and water have a direct line to the root system.
Installation of an aeration tube
By ensuring our trees’ roots have proper access to water and oxygen, we give them room to stretch their legs and thrive in their city environment.
Be good to your trees.
Because your trees are good to you.
By: Kristie Nairn, MA, Mmst