Here's a hypothesis for you. I'm guessing that you get some wind from time to time. Not saying full blown Santa Ana, but perhaps you do. But it wouldn't have to be high wind. Being in California your dew points are generally no higher than 50-55 degrees, and if you get an east wind, much lower than that. Point is that very little wind, with dew points that low or lower, and temps even in the 80's will be VERY drying. So this establishes some extra water stress. Now for the tree part. When deciduous tress sense the fast shorting days, and cooling temperatures, they prepare for leaf drop and winter long before you see any signs. One of the things they do is start sealing off the vascular system in preparation of the severing of the leaf from the truck to prevent water and nutrient lose. So while the leaf is still attached, it flow of water is already greatly reduced. Now along comes a day or two 80+ degrees with 15 mph winds, and you have a formula for dry toasty leaves just like your seeing. Whats more you would not get this earlier in summer, as the vascular system is open full bore then. It's only when nearing leaf drop that the flow is impeded enough to cause scorching. FWIW, I life in NW Arkansas where we have rain throughout the year. Dewpoints can easily be 70 at any time in September with temps in mid 80's, but we are nearing leaf fall. If we get a few sunny warm days with some strong wind, exposed trees can sometimes get the same leaf burn. Especially if the tree is not at all drought resistant like Sugar Maple which are very common here. So in short, I think it's tree physiology combined with dry California air and sunny skies. If I'm right you can try stepping up the water on warmer/windier days, but even that may not help. Arktrees

Unless the spot with the tree is especially prone to waterlogging, I doubt the wet summer and fall had an affect on the tree color. I was in NJ a few weeks ago and saw plenty of beautiful Red Maples. Now, the caveat is, Red Maple is one of those trees with fascinating genetic variation. Some trees regularly turn glorious red, while others are always yellow. Its just wierd like that ;-) If it was red last year, then something else (besides the weather) is likely affecting it. If it was yellow last year, it was probably mislabelled. I suppose it could just not like the surrounding soil too...

Hi...I live in Michigan, and planted an ABM last July in the back yard (the leaves were dark green). Two days later they turned color, and then within a week completely red. The leaves stayed this red color for the next 3 months without one leaf drop. This spring the tree grew as normal and the leaves are still green here in July. I planted another "green leafed" ABM in the front yard this past spring and guess what just happened in the past week...the leaves are turning red just like the one in the back did last year. I find myself looking around in the area at other ABM's and many are also turning red here in July. I called the Nursery and they said as long as the leaves don't drop...you are ok. Any stress to ABM's will cause premature leaf color. Last year it was transplant shock, and this year has been the lack of rain in Michigan. The one in the back has not changed this year because I planted it in a wet area. Hope this helps...Brent

I’ve got an autumn blaze Maple that will not green up. I’ve got other trees in the area that do just fine. It is Planted on all the farmland so I think the soil is OK. I’ve got another two trees down there is doing great and the neighbors is doing well. Any thoughts how to get it to respond?