The removal of an old tree is often necessary for safety. Dead trees can topple over or become hosts for pathogens, and depending on where the tree was located, it could have been blocking essential sunlight and casting too much shade on other plants. However, tree removal often means leaving a stump behind. In some cases, the stump is harmless, but removing that stump is often better for the health of surrounding trees. Even if the tree was removed for aesthetic reasons and the stump is healthy, it may be best to remove it anyway.
Fast-Growing Roots Might Still Grow
If the tree has fast-growing roots, the roots can continue to grow at least for a short time. The leaves of the tree are gone, so the stump isn't getting any food via photosynthesis, and that can eventually kill the stump. However, if the stump somehow manages to sprout, those leaves may help it survive. In that case, the roots will grow, and they could interfere with leaking sewer pipes and other plant roots. If you're cutting down a whole tree, it's best to remove the stump so that you don't have to worry about suckering or sprouting that allows the roots to keep growing.
Pathogens Can Spread
If the tree was cut down because it was overwhelmed by pathogens that couldn't be removed in any other way, the stump is likely to have those pathogens in it, too. Some pathogens — bacteria, viruses, pests, and fungi — can live in the surrounding soil, too, so you'll have to arrange for both the stump and the soil to be removed. Otherwise, the pathogens can spread to nearby trees or affect plants that you place near where the old tree was.
The Stump Still Takes Up Resources
As long as those roots try to draw in nutrients and water from the soil, they're going to take up resources that other plants could use. If the stump dies soon after the tree is cut down, that's not too much of an issue. But if the stump manages to sprout or sucker and develops leaves, then you're looking at renewed resource competition. Removing the stump is the only way to stop that.
Stump removal is a specialized procedure, so you need to contact a tree care company that has experience with stump removal to ensure the job will be done properly. Try to get the job done as soon as you can so that you no longer have to worry about that leftover tree stump. Contact a tree care company to learn more.