Greetings,
Well, both spring and fall tree planting are common. However, I am a huge fan of spring planting - especially when it comes to bareroot nursery stock. Fall planting bareroot stock in my neck of woods often results in uplifted trees due to frost heaving.
Balled burlap and potted stock can be planted spring or fall; but, again I prefer spring planting to reduce winter dessication - especially with conifers.
Since technical expertise varies across geographic regions, I would strongly suggest you consult with a local NY urban forester or Cornell Extension forester.
Best of luck!
