^ dan, I'm not going to pretend to give a hoot about attracting wildlife. In reality, I want most wildlife to stay pretty far away. Rats, snakes, deer, woodpeckers, coyotes, foxes, skunks, insects, rabbits and stray cats are not things I want in the yard. Sure some purty butterflies and certain birds would be nice but you have to take the bad with the good. Right now we have these certain territorial birds. In the morning when the dogs are let out the birds fly over and peck at them, sending the dogs running for cover. Mean birds that we could do without. We could also live without having our deck destroyed by woodpeckers. I also think it's highly hypocritical to live in a tract home 35 miles outside the urban core and act like I give a crap about wildlife, but that's me.

Oh, and those tree fertilizer spikes are ineffective. Don't bother with them. Just a way for retailers to make quick cash on uninformed gardeners. Somebody get me the smelling salts. I think I'm feeling faint! Sorry Jimi-don't take it personal! I just get a little stirred up every time those things come up! I've been a professional hater of those products for a number of decades now! Do take this to heart though; Stressed trees are rarely helped by fertilizer application. Quite often, the reverse is true. Adding nitrogen to an already moribund system can tip the plant over the edge. I think some above, knowing of the probable species you have, are offering good advice. I'm thinking too that if you were to adequately water such a large tree, you would essentially need to be watering the whole lawn on that side of the yard or whatever. Roots spread far and wide. I don't personally see the use of the rootfeeder in such an application. And too, your water having a high salt content is very troublesome. Between the fertilizer, which is mostly salts, and that water, things may be getting out of hand on the salinity index. More likely still, the tree has come to the end of its useful lifespan. Finally, you are anxious about losing this prominent tree. I get that, but contrary to what many folks say, young trees do grow quickly. Not only that, but it offers you a chance to try something new. And watching young trees develop is fun. +oM

I lost a newly planted Mountain Ash one particularly wet year and the nurseryman said yes, too wet -they prefer a light, very well drained soil (rocky, or on a slope). Once they are well established, I'm not sure if that's so much an issue unless perhaps it is planted in a consistently wet/compacted spot.

Not mountain ash/Sorbus which has pinnately compound leaves. This has simple leaves. It looks like firethorn/Pyrocanthus to me, but that's not a plant I've grown for many years, so I'll let others give you the specific kind. Edited to add: Looks like we all responded at the same time!