Yet another diseased (presumably grafted) Japanese maple cultivar. If it were mine I'd get rid of it.

Do you water it? Is the Pine tree roots growing among the Maple tree roots?
It looks as if it had been watered by the previous owner and now it's not. Just a theory though.

Bboy, I don't see any evidence of disease. What kind of disease do you think my tree could be suffering from?

Botann, yes that is pine straw left from a huge pine near by. I just had it cut down about a month ago. I am sure there are some pine roots that are sharing space with the maple but I havent seen any.
I do not water it since its an older tree and I assumed had a nice root system established. Maybe that's all it needs?

here is another photo of how large this tree is and how much of the new growth from last year is dead. you can also see that there is a lot of new growth in the middle of the tree which I would normally remove but in this case I am not going to right now

Here is a link that might be useful:

Maybe the neighbors can be some help with info like "ol George who used to live there sure used to water that thing all the time, God rest his soul"

Missybeth, what climate zone are you in or city are you near? Change anything around the tree?

And I'm willing to leave any "older" looking tree in place long as it isn't going to fall and kill someone. I'd kill for a big gnarly bristle cone pine in my yard just because everyone else already owns the same Bradford Pear. If it bothers you think about replacing it. If you can work with the sparse look keep it.

The tree is obviously well-established and with quite a few years under it's belt. If it were subject to bboy's catch-all disease theory, one would think that might have made an appearance before now.

The tree looks stressed to me - soil conditions look poor, lots of weedy growth in the area and I'd suspect insufficient watering. I'd also like to know where you are located as well. You may be able to encourage better growth by a few cultural details -- I'd get rid of any weeds, make sure the soil is not too high (tree planted too deep or has become deeper in the soil over time), apply a nutrient-rich, moisture retentive mulch and make sure you are getting adequate water down to the root zone.

Like toronado, I'd work with it for awhile to see if it can be rejuvenated before considering removal. It has (had?) a handsome growth habit developing that you would not replace easily with removal and replacement.

I am in zone 7b. The only changes I have made it to remove a huge pine tree that was about 20 feet away and I did remove a larger branch from the tree this winter. I am not sure if removing that branch was an issue since when I moved in the house the tree had a lot of dead growth just like this year.

I don't want to remove the tree I just want to make sure that I am learning as much as I can on how to keep it alive and thriving. I do hate the sparse look but I know that I cant go in there and just start chopping. It will be a slow process to reshape the tree and thats ok too. I just want to make sure that I am doing the right thing here thats why I am getting advise from you nice people :)

I will ask the neighbors and also try a giving it some water more often. Maybe it was just fighting with that pine for resources.

Probably Pseudomonas, even has black twigs visible when pictures enlarged.

Most Japanese maple cultivars such as 'Sango Kaku' and 'Oshi Beni' are highly susceptible

Here is a link that might be useful: Information on Maple -- Bacterial Leaf Spot and Dieback, An Online Guide to Plant Disease Control, Oregon State University

For a picture of the results of infestation with that...

Japanese maples are also very susceptible

Here is a link that might be useful: Information on Maple -- Verticillium Wilt , An Online Guide to Plant Disease Control, Oregon State University

Personally, I don't see any obvious signs of diseases......and I work with Japanese maples on pretty much a daily basis. I think the tree is suffering from some inattention and neglect -- the pine tree may very well have presented excessive root competition and depleted soil conditions.

At this point, I'd follow the approach you seem inclined to take. Work with the tree and see what progress you make this season. Clean out weeds, attend to the soil and watering and judiciously remove dead wood. Do sterilize your pruners, though - secondary infections are often common in dead plant tissue. I've seen some pretty sad looking JM's come back to life with appropriate TLC - these trees are not nearly as delicate (or as disease ridden) as some would have you believe. Even if the tree continues to decline - and I see no obvious reason it should if given some care - all you will have wasted is a little time and effort.

I think I will just try to give it some extra TLC because I don't really see any sign of disease either. The leaves are not dying, the tree jut isn't filling out. If that doesn't work I will go from there I guess. Thanks so much for all the advise!!