It's really hard to know what happened without more specifics (when the tree was planted, how much amendment was used, how the tree has been watered, etc, etc), but a couple of things really do stick out as a possible problem...

First, the backfill soil should almost never be amended when planting trees and shrubs. Hopefully the manure was at least well aged and composted. Soil amendment introduces drainage and root system growth issues. Many people add amendment to clay soil hoping to improve drainage, but, unless you could amend the soil down to a level where a better draining soil exist, such amendment actually make the situation worse.

The other thing that is of concern is the drip irrigation and the damp soil. There's nothing wrong with drip irrigation or occasionally damp soil, but it makes me wonder about how the tree has been watered. When trees are newly planted, they need to be watered more than when they become established because their root system is not sufficient to supply enough water. However, overwatering can be just as hard on most woody plants as severe drought. Too much water causes root rot. The best way to determine how much water is needed is to stick your finger down into the soil both around AND in the rootball. When a different soil is present in the rootball as compared to surrounding soil, the rootball may dry out long before the surrounding soil or retain water longer than surrounding soil (depending on the soil types involved). That's one reason some people prefer to plant only bare root stock (I'm still not convinced that is necessarily best). Soil below a couple of inches should not be allowed to dry out, but the top of the ground should dry out in between watering.

Here is a link to what I believe is a fairly complete set of planting instructions for woody plants. I haven't had time to add illustrations, but hopefully everything is understandable and concise.

Here is a link that might be useful: Planting a Tree or Shrub

I do think they don't like to be in full sun. I have two, and both are in what I guess could be called very bright shade, at the edge of larger canopy trees. They both seem happy. One was planted last fall, the other this past spring.

Thanks everyone. I just planted this J. Maple in June. It is on the east side of the house getting full morning sun. I'll get my fingers dirty tomorrow and check the soil wetness. Hope it makes it in this location, its the finale of the bed...

My poor Coral Bark is dead. I believe it was too deep and the soil too wet. It seems most things I've planted have sunk lower than I thought they would. I'm also realizing the necessity to add sand, lots of sand, to combat the thick clay I'm planting in. Compost is just not enough. Luckily, I have a warranty on the coral bark and can get another from the nursery.

SAND! Heavens no! Clay + sand = brick. You don't want to plant your trees in brick!

Did you happen to read the link I posted above? If you dig your planting holes properly, your plants won't sink. If you stop using amendment (or at least use it VERY sparingly), your woody plants will fare much better. To borrow a couple of sentences from one of Linda Chalker-Scott's documents...No scientific studies to date show any measurable benefit of soil amendment except in containerized plant production. Plants grown in native soil consistently show better root establishment and more vigorous growth.

Ok, it's been a while since I read the above, and I admit forgetting the advise. But when I look at the thick chunks of clay I'm dealing with, its just hard to believe anything can survive in it. I am not replacing the maple yet, so have time to determine how to proceed. Will look again at your links and others. I may be able to make it to the ETPS. I hope I can get more good advise on how to garden in the dense clay soil. Thanks again...

Sorry about your JM - they are my favorite. When I lived on the farm - we had 5 of them. But after we moved - I just haven't had much luck with them. I got a baby at the spring swap...but the heat this summer was just too hard on it and it didn't make it through the July heatwave.

Good luck with your next one - hopefully you will get some good advice at the swap and have a successful planting this time.

Tiffany

Getting ready to plant a coral bark in a somewhat shady area. A little apprentice since a blood good that was there for 15 years died this past winter! I guess I need to relax as this past winter in Philadelphia was harsh. Besides adding some compost, does anyone offer advice on writer protection? I will also read the above mentioned link

Adrianne, don't add compost unless you are using that as a mulch. Mulch (especially an organic mulch, like shredded hardwood mulch) can be useful. Now is not the best time to plant a tree, so be sure to monitor soil moisture carefully, especially throughout the summer.

If it were me, it would depend on how root-bound it was and on how easily I could care for it in the pot. As long as you can baby it though summer, planting it now might be the easiest thing to do. Just be aware that extra care may be needed to get it though this hot, stressful time of year.

Finally getting back to the GardenWeb and finding out what Houzz has done. I am happy to report 5 years later (Gosh, where has the time gone!) I have 2 beautiful Coral Bark Maples. So glad I tried again.

Should I cover my coral bark maple I planted two weeks ago when winter comes.? I am in Philadelphia and last year we had a very hard winter. Also, how often should I plant my four foot tree.

Adrianne Moore,

My thinking on covering your tree is that, unless you plan on doing it from now on, I wouldn't. The tree should have plenty of time to become reasonably established before this winter. That doesn't mean it couldn't help. But, it might also help next year...and the year after that...and the year after that. When will you stop?

I don't understand the second part of your question, unless you have it in a pot instead of in the ground.

Just a general comment. I have found that Japanese Maples have been some of the easiest plants to get to grow. I've planted a bunch and I can't remember any of them dying - yet.. I honestly wouldn't worry about the soil much. I have clay and they don't seem to mind. Plant them in fall or spring when the weather is good. Give them an extra heavy drink of water every week or two if it doesn't rain. They like some shade. Full sun and they will probably have burnt leaf edges by late summer but if you can live with that it doesn't seem to hurt them.