this sugar maple (with very poor form, had the top broken out during storm) with in the past few days has become very bronzed. the leaves are curling and are crunchy. can not detect any signs of spider mites or other pests. we have had ample rainfall, flooding conditions in parts of the city the past few weeks. as you can see in the picture, everything else is very lush and green. the tree well (mulched area) has obviously been treated with a herbicide recently. i am guessing this is the cause. any thoughts?
Do you know more of the history of this tree in this site? The reason I asked is why do you feel the curled leaves are due to a possible herbicide (weed and feed, considering the color of the lawn)? The speckling (reddish orange colored areas) on the leaves does show a pattern of destruction similar to having some chemical injury but the lower leaves do seem to be okay for now. It does seem to me that this tree has not been deep watered enough which brings to mind the possible weed and feed and the amount of water or lack thereof this tree has been getting. A series of sun fried (beyond a scorch as shown below) leaves all turn the same color and also have the curving and the distorted leaves. A quick fry due to sun and wind damage and not enough water and then have a weed and feed application or causal damage from drift could have all caused these symptoms on this tree. Below is a photo of one of our Tsuma gaki Maples that all of the top growth just got fried to a crisp by the intense sun with not enough water pumping through the plants system. There was no missed watering involved, we just could not give this tree ample water fast enough. This photo was taken a year ago. As we can see a pretty uniform toasting. All the deadened areas were trimmed off to help generate new lower growth from what was left of the tree and now the tree is fine again and has already reproduced much of the wood that was lost. The reason for the example is even with a roasted plant there is some margin left for recovery. No matter what caused the damage to this Maple, deep water this tree for a while until you know how much wood loss there is and will be and then prune off all of the deadened areas and hope for a speedy transition. Some institutions say to fertilize when this happens but I'd be hesitant to do it as part of the problem may be due to a fertilizer with not enough water given to the tree but I also sense a herbicide at work here by the discolored areas on the surface of the curled leaves. Good luck with the tree. Jim
thank you for all the replies. i guessed herbicide injury since the area underneath had just been sprayed and it was within a few days of the symptoms showing. i know it is not from lack of rainfall since we have had 36 consecutive days of rain. yikes! i was either suspecting too much water or herbicide injury. thanks again!