New garden apple tree died possibly fungal?

Just lost a honeycrisp dwarf apple in about 3 days.  Went from dark green foliage with some light green new growth to everything dead and brown looking. I also lost 2/3 of an elderberry about a week ago. Almost the exact same browned leaves and tips of ranches progressing within about 48hrs for the elderberry. The one branch of the elderberry that did not die is lying on th ground but has new growth and new growth is coming up from the center.

Background
I live southwest of St louis mo.
First year back to eden garden
Dealing with a major aphid problem I didn't know I had till I started looking around after losing the tree.
The tree is located in an area where most of the runoff flows through and we just had a somewhat heavy rain event about a day before it started to brown.


I think it is most likely fungal due to the proximity to the rain event, the aphid infestation and the fact that another perennial nearby fell just as fast. However after some googling I could not find any common disease or fungal issues. My first inclination was herbicide because I could draw a straight line from the branches of the elderberry that died and the apple tree. However that is out of character of my neighbors and I don't use anything like that. We are right by a lake but I was care full when planting to give a rough hole to prevent a fish bowl developing.

I'll take it out if need be but I would rather cut it back hard with possible regrowth next year than rip it out but I also don't want it to spread to our other two apples which are up hill of this one.

Do you know if there has been any spraying at the lake? That looks very much like the results of Herbicide drift or leaching than fungal, I looked as closely as I could in the photo for signs of fire blight or other problems but the leaves don't show blight signs.

How often have you watered this tree? sometimes freshly planted trees are either over or under watered and that results in browning leaves.

To check to see if the trunk is alive you need to make a cut at the tip of one of the branches, green means it is still living, brown means it is dead there and you will need to make another cut closer to the trunk.

Redhawk

Thank you so much! I will be checking tomorrow at light! I didn't think there were any blight marks, no cankers, no "grey goo". Over watering is very likely. We've been having back and forth between downpour and then blazing heat for the last 3 weeks. It is mounded a good 4 inches up but I know during heavy rain ground water can rise as high as 3 to 4 inches below the soil surface. If it's alive do you think I should prune it back to live wood?

The neighbors did hire a lawn company just a week or so earlier it's possible they had a first time deal or something, they rent and there is no way they would pay to fertilize or herbicide their yard. We are very grateful that our neighbors do not hold to the extreme herbicide and fertilize regimen you get in most subdivisions.

Bryant RedHawk wrote:
To check to see if the trunk is alive you need to make a cut at the tip of one of the branches, green means it is still living, brown means it is dead there and you will need to make another cut closer to the trunk.

Redhawk

IT LIVES! Thank you so much for your help! The longest and worst looking branch was green all the way out the tip. Any suggestions for helping prevent this in the future or will the tree just get strong enough to shrug off its feet getting wet? We have heavy clay so our drainage is so so at best.