floraluk- 'Flowers may have a scent or not. Leaves may have a scent or not. Flowers and leaves on the same plant do not necessarily smell alike.' So, I guess I can conclude it is not the Cherry Laurel because the leaves should have a scent regardless of whether it flowers?

If you need the room for the orchard filberts then you will want to take the existing native ones out. Otherwise it is a matter of personal preference - if you might like the native species enough to keep it there. Try reading up on it and seeing if there is anything about it that might interest you. Like non-resistant kinds of orchard filberts local plantings of corkscrew filbert are currently being spoiled by eastern filbert blight. So you may soon see your specimen develop large sections of dead branches. Even to the point where the tree is mostly gone. It says here the two orchard cultivars you mentioned above are highly resistant, so maybe you are attuned to this problem. If not you will definitely want to continue choosing kinds that are. Hazelnut (Corylus avellana)-Eastern Filbert Blight https://pnwhandbooks.org/plantdisease/host-disease/hazelnut-corylus-avellana-eastern-filbert-blight

For starters maples produce opposite leaves - at every point a leaf joins the main stem there is another leaf directly opposite.

"But no one has told me what the difference is between Prunus laurocerasus and Prunus caroliniana. No such clarification was posted. My original question was about identification of a tree. Is there some reason to believe that I have one, rather than the other? " It was properly identified by botanical name by Embothrium. Prior to that, just one of many common names was used for ID however that common name is often applied to both species. Prunus caroliniana is a native species that includes Texas as part of its natural range. It would be very unusual for Prunus laurocerasus to pop up spontaneously in your area but entirely natural for P. caroliniana to do so. It is also more tree-like in habit than Prunus laurocerasus, which is most often grown as a large shrub with no discernible trunk and the leaves present somewhat differently (smooth margins for one and slight serration for the other). As to the negative attributes you list, other than the propensity for P. laurocerasus being invasive in specific areas, they are just not serious enough to worry about.