Corkscrew Willow Problems

[Firefighter]

I planted a corkscrew willow about 15 months ago. It was a sapling at the time and up until about 3 months ago it was growing and looking just fine. For about 2 months the leaves have been turning yellow/brown and have brown spots on it. Also the skin of the bark on the main trunk separated from it the tree in some spots. Also I have what looks like dirt or coffee grounds coming out of parts of the trunk. The leaves are also dropping off at an alarming rate. The branches look fine and healthy to me. About last April I cut back the grass around the trunk (about 3 feet in diameter), added a bag on compost and some fresh dirt and mulch and it did great until about late June until the above issues started. About six weeks ago I gave it some Bayer Advanced Feed and Protect (said it would protect against insects and revitalize browning trees) but that hasn't helped either. It's just getting worse actually. I think it gets plenty of water and the soil is good I think because I have a very healthy lawn and tons of earthworms. I'm wondering if I should cut the grass back again (it's grown within one foot of the trunk now) and add more dirt and some compost. Any help would be appreciated.

Thanks.

 

[Firefighter]

One picture is back in June (on the 1st birthday on planting the tree) it had been a couple months since I had cut the grass back, added dirt/compost and the mulch and it was growing and looking great. The other pic with all the leaves on the ground is what I have going on now. As you can see the grass has grown up quite a bit and I'm wondering if it choking the roots of the tree off.

 

[Firefighter]

Sorry I'm new here. This should probably be moved to the homeowners help forum.