Autumn Leaves Are Falling Down: Why Is My Tree Losing Leaves in Summer?

As we work our way through the end of summer, we tend to hear a lot of similar concerns from our customers: how come my tree is already losing its leaves? It isn’t Fall yet, after all, and losing leaves can be a sign of interior decay, so your concern is definitely warranted. That’s why, in this article, we’re going to discuss the reasons your tree might be losing leaves at the end of summer, and whether or not you need to worry about your backyard forest.

Some trees will naturally shed leaves during the summer, like live oaks and ornamental cherries. In fact, most ornamental trees, younger trees that aren’t fully established yet, and trees that are small in size are likely to drop leaves in the summer. As long as these trees still appear healthy (green leaves, bendy twigs, and new buds), and the falling leaves don’t have any leaf spots, holes, or indications of disease or infestation, then they are most likely just fine.

Overgrowth

​Sometimes, trees get a little overzealous in the spring and grow too many leaves. When summer comes, with its drying heat and reduced rainfall, your tree has to backpedal.  Since it isn’t getting enough water to support all those leaves, it will let the least  productive ones yellow, die, and fall off.   Basically, your tree eliminates the weakest link(s). ​​​

It’s pretty easy to determine if this is what’s happening with your tree—just look at the color of the fallen leaves. If they are yellowed or browned pretty evenly, with no consistent spotting, then they are definitely just the tree doing a little healthy maintenance. To help it out, consider giving it some water once or twice a week. This should stop the premature dropping and get your tree back to tip-top shape.

​If the leaves that fall are mostly green and appear healthy, this is the result of overcrowding, rather than lack of resources. Your tree didn’t grow more leaves than it could support; it grew too many leaves for the space it has! There’s not much to do about a tree that got too big for its britches, but rest assured that your tree is just fine.

​Disease, Pests, and Decay

On the other hand, if the leaves appear to be unevenly yellow, or have clear spotting or pockets, or are fully dead and dry, this might be cause for concern. There are a lot of environmental and health factors that can lead to a tree losing its leaves like this, not all of which are cause for concern. To figure out whether or not you need to worry about your tree in this case, first determine a rough percentage of how many leaves it has lost—is it closer to 10%, or 90%? If you feel like your tree has lost over half its leaves prematurely, it might be time to call your friendly neighborhood arborist.

If your tree hasn’t lost more than half its leaves, the next thing to do is look at its new growth. Namely, look at the twigs and buds. Healthy twigs are bendy, and if broken, will be green on the inside. Dead twigs are dry, brittle, and dark on the inside. Buds should be some shade of green, whether pale or vibrant; dried-out buds are dead or dying. If the new growth is in good shape, then that tree is still alive and well, and there’s probably an external factor that caused the leaf drop. You can try watering once or twice a week and look for improvement. If, after a few weeks, you’re still seeing a smaller percentage of leaf drop, it might be time to call in the professionals.

If the buds and twigs aren’t in such good shape, however, then at least that part of the tree you could reach is probably dead or dying as well. To check your tree for disease and decay, check out these signs that your tree might be in decline. If you think your tree might be infected, it’s definitely time to call the professionals!

​Verticillium

Sometimes, rather than seeing leaves dropping prematurely, you see trees coloring prematurely. This isn’t always cause for concern, but keep your eye on the location. If the color is concentrated to a chunk at the crown (the top of the tree), or is clearly only along one branch, your tree might have a fungal disease called verticillium. Essentially, this disease impacts the vascular tissue of the tree and prevents water from getting where it needs to go. Verticillium is, unfortunately, usually fatal to the tree, but you’ll still probably want to have a certified arborist take a look to confirm that’s what’s happening, and assist you in figuring out how to take care of the situation.

​Dormancy

Some species of tree go dormant in the late summer when the days get longer, hotter, and drier. These trees will lose most, if not all, of their leaves fairly quickly. The easiest way to tell if this is what happened to your tree is to, again, look at the new growth. If the twigs and buds look green and healthy, then your tree is still alive and just taking a little break. But if the twigs and buds are dead, your tree might also be dead, and you may need your local arborist to come examine it and determine whether or not it needs to be removed.

​Dehydration

Another instance of leaf loss in the summer can look like all the leaves on your tree drying out and turning brown and crunchy, seemingly overnight. They may all fall to the ground at once, or they may stay attached to the tree, even though they’re dead. This is definitely a sign that your tree just didn’t have enough water to sustain itself. A look at the twigs and buds will help you determine whether or not your tree is still alive and whether or not it can be saved.

So there you have it! If you think one or more of your trees is exhibiting any of the symptoms listed in this article, or in our article on the signs of tree decline, please don’t hesitate to give us a call, shoot us an email, or request a free estimate on our website!

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Author

Emily Casuccio is sister and sister-in-law to Rebekah and Scott Rushing, and has over half a decade of experience in copywriting, copyediting, proofreading, and developmental storyboarding. She's worked with both published and undiscovered authors on both fiction and nonfiction, and takes pride in supporting local businesses. Her passion lies in the written word and helping authors of all capacities realize their dreams and achieve their fullest potential. To learn more about her, read samples of her work, or contact her, visit her online portfolio.

Sources:
Why Are Trees Losing Their Leaves?
Trees Losing Leaves
Why Are Trees Losing Leaves in August or Early Fall?
Summer Leaf Yellowing and Drop