A tree peony will have a brown woody stem that remains even in a Montana winter. Just possibly, it might not be alive by spring but there would be a brown woody stump. A herbaceous peony will completely disappear, and that sounds like what you've got.

I suppose too you might have fed the cherry tree...or the lawn that it sits on...and did likewise for the peony.

Cherry trees need not to be fertilized.....and neither does your tree peony....much better bloom when not fed.

Possibly where its at...in the middle of your lawn, it ..the lawn, gets plenty of high nitrogen lawn fertilizer....maybe with a ratio of 21/7/7....24/6/12...something along those lines.

So much nitrogen, feeding your lawn is good.....unfortunately, it is having an effect on your peony...and will too on your cherry.

Give your peony a wide berth where your lawn fertilizer is not so affecting it.

And....I suppose it was your doing to put the tree peony so close...or vice versa...to that darn cherry which is maturing out and wants to hug your peony.
Don't let it. Get it out of there and give it as good a sun as it deserves.

Feed your lawn........starve your peony.

Without any woody stubs, I think your Peony is herbacous. You might have lost the tree part, grafted herbacous root has taken over. Most tree peony plants sold are grafted.
If you still wish to keep it, I also would move the plant to a more sunny location. Try for morning sun, afternoon shade. My Peonies like that, full day sun is just not available to all of them. I have two tree peonies that get afternoon sun, have not had any blooms on them for 3 years. Plenty of time to settle in and flower. I have decided to move them this fall, see if another place will get them blooming. Good foliage, not fertilized heavily, just manure, no buds or blooms.

Thanks everyone who helped me. Regarding diane's advice. I need to clarify that I do not have a lawn, at all. We live in the mountains, and the peony grows on a terrace and so I am not fertilizing any lawn, for fertilizer I used composted rabbit manure mostly supplimented with bone meal and potash.
Interesting that goodhors thinks it should have morning sun, as that is the opposite of what was in my garden book before I planted it. Howrever, if that's what works, I think I'll move it this fall. I have another terrace where the rest of my peonies are and I'll move it there. In case it turns out to be a real tree peony does any one know how tall it will grow at maturity?
Thank you all for your help and and messages.
Borde

I have 10 tree peonies, some are more than 7 years in my garden and have never bloomed. Some, like the one pictured below are 5 years old and bloom every year. They are tricky in zone 4 and colder because the buds for next year's bloom are formed from now into the fall and they can freeze in the winter and you will lose next season's bloom. Some are hardier than others. The one pictured is 3.5 feet tall and I usually protect it with a wire cage and straw covered with plastic. I have a pink one that died back to the roots and the rootstock was "Phoenix White" and it emerged like a herbaceous and the stems hardened and became woody and in subsequent years it bloomed white.
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