I recently had questions about Autumn Blaze maple leaves turning red. Early fall color in trees has also been reported in other counties.
This is usually a sign that maples and other types of trees are responding to stressful growing conditions such as compacted soils, drought or extremes in temperatures. This may also be a response to mechanical damage.
Tightly compacted soil, consistently wet soils from overwatering and drought are detrimental to maples and other trees.
These conditions can cause trees to lose leaves or develop fall color early in the season. The stress is mainly a response to diminished oxygen or water supply to the roots.
Over time, if conditions are not changed, the trees will become less healthy and may eventually die, especially maples.
Damage to tree trunks from lawn mowers, weed trimmers, animal feeding or sun scald reduces the flow of water and nutrients in a tree, leaving the tree weaker and susceptible to other issues. Drought stress also reduces water and nutrient flow in trees.
Avoiding mechanical damage to trees is important. Use mulch around the tree to avoid hitting the trunk with the lawn mower or weed trimmer. Protect young trees from animal feeding with a ring of hardware cloth during winter. Protect tender-barked trees from sun scald with the correct use of wrap during the winter.
To help relieve soil compaction and maintain a cooler soil and consistent moisture, not too wet and not too dry, apply a mulch layer over trees roots.
Ideally, use a mulch layer about 2 inches deep a few inches out from the trunk and all the way out to the drip line of the tree. Never place mulch directly against the trunk. Reapply mulch each year as needed.
Sometimes a tree is simply stressed but still healthy enough to recover. If damage to the trunk or root system is too severe, mulching may not save the tree. Do not fertilize trees stressed from soil compaction, heat and drought or mechanical damage; unless low fertility is a known issue.
Now back to Autumn Blaze maple. This is an example of "not judging a book by its cover." While these trees can be beautiful when in fall color, they do have issues that may lead to early fall coloring.
Autumn Blaze, also known as Freeman maple, is a grafted hybrid of silver and red maple. Like the parent trees, Autumn Blaze maple is a tender-barked tree susceptible to sun scald during winter. And it often develops iron or manganese chlorosis in our high pH soils.
Being fast-growing, it has softer, brittle wood susceptible to ice or wind damage. It can develop shallow surface roots that are a nuisance.
And for some reason, maybe graft failure or maybe due to being planted too deep or being overwatered, Autumn Blaze often dies. The first sign is early fall coloration and leaf drop.
When selecting trees, do not judge a book by its cover. Learn more about a tree before selecting it. Every tree has pros and cons; but some cons are harder to deal with than others.