Hi joypdx ! I think the average height for a crabapple is 15-20 ft., so probably a good idea to move it. The species and the cultivars all have similar looking leaves, so the exact ID could be rather difficult to pin down. The best way to identify them is by their fruits, (which isn't an option at the moment). Also keep in mind that many of them sucker, and you will be often removing them. A mower would keep them in check, but there will be suckers that the mower won't reach.

Bear in mind that it could also be a seedling from a domestic apple. There's no way of knowing at this stage.

based on its location.. i would assume the seed flew out of a birds butt.. while it sat on the fence..

you will have to let it mature to flowering and fruit production age ... which could be 3 to 5 years... by which time.. you probably wont me moving it..

it will not be a named variety of apple... and odds are it wont be a pretty apple lik you ee in the store.. and it may or may not be tasty ...

as to a crab.. it may or may not hav3e pretty flowers.. and it might not be resistant to fireblight .. etc ..

frankly.. its about 99% certain that anything bird or wind sown is not valuable... its the genetics.. and the fact that the horrible weeds.. are the ones that plant themselves all over the county...

i would get rid of it.. why waste 5 years to find out.. and if you are interested on an apple or crab.. spend a few bucks to buy a quality named varietal ...

and finally.. trees dont stop growing at some magical height... they achieve a given size estimate and continue growing past it.. as the decades roll on .. your need for less than 12 feet.. would make me ... again.. remove it...

if you want to learn by experimenting.. let us know.. and we can tell you how and when to move it.. if you tell us where you are.. big city name... but in general:

https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub

ken

Thank you for the replies. I agree. Plan to remove it.