Early Tree Leaf Drop?

An observation this year that I haven't recalled seeing before.

There are two Norway maples near my property that are experiencing sudden leaf drop independent of other maple/maple like trees. The leaves have suddenly shriveled up, turned brown, and have been dropping onto my lawn. The nearby Boxelder trees, Ginko, Redwood, and other trees appear unaffected. While we have had some high humidity and warm temperatures, there has been semi-frequent rain and some days of relief.

Have you seen any early leaf drop yourself this year? Got any thoughts why only one kind of tree might be showing signs while others are not?

I hope to learn something new!

I had the exact same thing happen with my two Suriname cherries. One dropped all its leaves (as they do for winter) and the other didn't. They were planted next to each other on the very same day and receive the same care (youngish trees, 7-ish years old). Both are now throwing buds. Go figure.

I don't know about you but where I am, "weird" is an understatement for how the weather has been. We had a hot snap and now everything is leafed out and flowering. Then a bomb cyclone came out of the South Atlantic full of polar air, I'm hoping the fruit flowers survive. The snow peas, on the other hand, are having the time of their lives and I'm getting a bumper crop, daikon radish too. Meanwhile, the climbing striped fava beans, which are usually a reliable winter crop here, have tiny 'i'm so stressed' leaves and almost no flowers are setting beans. A weird year.

Yeah Norway maples near me did something similar last summer, just randomly stress-dropping while everything else was fine. Looked alarming but they bounced back. The weather thing rings true, it's been all over the place this year, hard to know what's normal tree stress anymore.

Summer leaf drop on certain trees is normal here, where we have summer droughts. Sometimes they seem to drop half their leaves and keep the rest. We haven't lost deciduous trees, but the cedars have been in decline for decades and there are a lot of dead ones around. The forest used to be too dark for much undergrowth, and that is no longer the case.

What's even weirder to me is that my June bearing strawberries have been putting out the odd berry in the last couple of weeks? All I can figure is that June was cool enough they got themselves confused?

In our climate, it's pretty normal for big leaf maples and a few other water loving trees, to drop their leaves in early August.   It's a survival mechanism for not having any rain since april.

I can imagine if a tree isn't acustom to drought or doesn't have strong reserves, it would drop leaves much sooner to stop moisture loss.

This year we had a bit of rain in the summer, so the trees might hold out until fall.  When that happens, it's glorious as instead of turning brown, the leaves make bright colours before dropping.   This is maybe once every 7 years.  The last time i can remember is 14 years ago when a family member died so I couldn't enjoy it.  So I hope this year might give us pretty colours again.

Thank you all for the bit of relief, it is nice to know that this is a normal process when certain conditions are met.

To be fair, I'm pleased with the prospect of having some free mulch material to utilize before the big leaf drop occurs. It also helps me balance out my garden trimmings when placed in the compost.

Hmmm, all these trees from various backgrounds!  We’re lucky to have such diverse trees for our planting pleasure!

Norway maples, box elders, gingko and redwoods are from different ecosystems, different regions of the world and adapted to different conditions, and just like all us permies in our different situations, trees from China, Norway, west coast North America are not necessarily going to respond to various conditions identically.

But good job on noticing the variations occurring.  Let’s build up a data base, and we’ll get to the point where we can be “citizen scientists”, generate and maybe test hypotheses.

I don’t know about the rest of its native range, but box elders are native here.  They grow as part of the riparian community.  And we can get hot and dry in the summer.  So, just conjecture, but it appears box elders are adapted to hot and dry spells if they have adequate water, while 100% guessing on this next part, Norway maples maybe developed in a more humid and not so hot conditions.  Dropping leaves can be an adaptation to too hot and too dry, that might occur immediately or be delayed.  

And as mentioned up thread, there are trees that go as far as they can through the annual summer dry spell then drop all their leaves and wait until spring before leafing out again.  California Buckeye is the one I know from childhood.

Walking around the farm this morning, the native species losing their leaves are cottonwood, alder, big leaf maple.  Imported species like hazelnuts and chestnuts are also leaf dropping.  The younger the tree, the more dramatic.  We're about a week behind on this trend from a normal year due to rain in july.

Generally speaking, trees will unexpectedly drop leaves like that under environmental stress.  In my experience, this usually means too hot and/or too little water.  I have planted many black locusts on my property, which is right at the edge of their native range.  I see a few around my area, but mostly they begin appearing 30-minutes by car further up the mountains.  Predictably, on my land they drop leaves by the end of summer, only to regain them as cooler autumn weather sets in, only to loose them again over winter.

While this is clearly a stress response, it is not enough to seriously hurt the trees - they still grow like black locusts, which is to say like weeds.  Were I in an even warmer zone, doutbless I'd have trouble growing them at all.  But by the same logic, the stress response is specific to these trees based on their growing preferences.  I have seen a similar pattern in currants and gooseberries I've planted, similarly at the very edge of their tolerance for hot conditions, but not with countless other species more well adapted to my zone.  That doesn't mean there is anything "weird" about the weather, only that certain species can handle it while others struggle.  Whereas the black locusts are clearly winners for me, despite their challenges (and their thorns!), I've yet to decide if I shall give up on the gooseberries or keep trying to nurse them along at the edge of their ability to thrive.

BTW, I have noticed that now, in mid-August 2026, my black locusts have yet to loose their leaves.  This has been a fairly cool and notably wet summer for me.  Surely, that is no coincidence.

Of course, the pattern described above assumes that your plants suddenly dropping leaves out of season will in fact bounce back at a later date.  If they drop leaves suddenly and then die, it may well have nothing to do with their climate tolerance; they probably contracted some virus.  Of course, having said that, if they exist in a stressed state due to extreme heat relative to their preferences, they were likely more susceptible to disease in the first place by virtue of being stressed.

Matthew Nistico wrote:Generally speaking, trees will unexpectedly drop leaves like that under environmental stress.  In my experience, this usually means too hot and/or too little water.  I have planted many black locusts on my property, which is right at the edge of their native range.  I see a few around my area, but mostly they begin appearing 30-minutes by car further up the mountains.  Predictably, on my land they drop leaves by the end of summer, only to regain them as cooler autumn weather sets in, only to loose them again over winter.

While this is clearly a stress response, it is not enough to seriously hurt the trees - they still grow like black locusts, which is to say like weeds.  Were I in an even warmer zone, doutbless I'd have trouble growing them at all.  But by the same logic, the stress response is specific to these trees based on their growing preferences.  I have seen a similar pattern in currants and gooseberries I've planted, similarly at the very edge of their tolerance for hot conditions, but not with countless other species more well adapted to my zone.  That doesn't mean there is anything "weird" about the weather, only that certain species can handle it while others struggle.  Whereas the black locusts are clearly winners for me, despite their challenges (and their thorns!), I've yet to decide if I shall give up on the gooseberries or keep trying to nurse them along at the edge of their ability to thrive.

BTW, I have noticed that now, in mid-August 2026, my black locusts have yet to loose their leaves.  This has been a fairly cool and notably wet summer for me.  Surely, that is no coincidence.

Of course, the pattern described above assumes that your plants suddenly dropping leaves out of season will in fact bounce back at a later date.  If they drop leaves suddenly and then die, it may well have nothing to do with their climate tolerance; they probably contracted some virus.  Of course, having said that, if they exist in a stressed state due to extreme heat relative to their preferences, they were likely more susceptible to disease in the first place by virtue of being stressed.

Thanks for posting this on black locusts Matthew.  I planted some seedling black locusts earlier this year.  I would have been worried anout what might have happened if you hadn’t told me their leafdrop and regrowth habit!

Looks like the east coast of canada is having their first expierence with this early leaf drop... well, first in a generation.

https://www.ctvnews.ca/canada/article/maple-trees-shed-leaves-mid-august-is-it-a-sign-that-fall-has-arrived-early/

I have a serviceberry tree that is native to the region; ever since it was planted, it has dropped leaves over the span of months.  The leaves get a washed out color and gradually fall.  I also have a Stella cherry that has had noticeable leaf drop this year, but to be fair, about half the tree was amputated because it was showing signs of brown rot and that half of the crown never leafed out.  That tree might not be long for this world.