Callery pear? Here is a link that might be useful: Pyrus calleryana

"any opinion as to it root system .... e.g. i like to grow hosta under trees" Not too bad, they generally have a fairly rich ground flora under them in the wild. You'll easily be able to find something better than Hostas (Bo-o-o-o-oring!!!) to grow under them. Resin

Hmmm....it's definitely not an avocado as those have singular leaves instead of a leaf made up of multiple leaflets like your tree has. It really looks like a young specimen of one of the ash trees to me. There are lots of types that are grown around here, Shamel ash being one of the most popular, but there are others too like Arizona ash (Fraxinus velutina). Maybe google for that one and let us know what you think? I'm sure others will chime in too as they catch up from Thanksgiving. Below is a link to the entry for Arizona ash on the Desert Tropicals website. Happy gardening! Grant Here is a link that might be useful: AZ Ash on the Desert Tropicals website.

Sam, Clement, Resin and bboy, thank you very much for your answers. All three P. menziesii should be of almost exactly the same age. Is it a possibility that genetic variances between them caused one's bark to mature faster? It is quite likely that the third one is P. pinaster since that tree used to be planted on small scale for forestry around where I live. Thank you for the compliment, Sam. :) Taxus baccata is a conifer which is wild growing here anywhere; presumably because of its extensive use for hedges. Close to the one I found were numerous "normal" (single coloured, dark green ones) so this one catched my eye immediately. This one has smaller, more sickle shaped leaves which are green on the inside and bright-yellow across their edges. This post was edited by liopleurodon on Fri, May 17, 13 at 5:23