Quercus Puzzle

[johnw]

We saw these three (plus 1 other) oaks in the Annapolis Valley last Wednesday.  The leaf lobes were rounded and very shallowly indented.  This very narrow habit is quite unusual.

Quercus rubra is native here and Q. robur is naturalized, it's neither of those.  Could be an American species.  Bark resembles Q. bicolor.

Any ideas?

johnw - +11c, foggy and windy here; +22c in the Valley.

[johnw]

Wjile we're on the subject here is another group of oaks just a few kilometers from the previous mystery ones, on the campus of Acadia University.  These I first spotted on the way to a concert in August 1968 and have driven us mad since then.  They are obviously extremely slow-growing as they really have not grown much at all despite fine soil.  Could that split point to a hardiness issue   - petraea?  A UK friend casually pronounced them Q. petraea as we drove by them one day in the late 70's, I believe he later entertained the thought they could be robur x petraes or the reverse.  A friend photographed them today for me.  Ideas or thoughts?

johnw

[Anthony Darby]

Quercus rubur is the English or pedunculate oak, whereas Q. petraea, the sessile oak, is more common in Scotland. The difference is the former has its acorns on stalks; the latter attached directly to the leaf-bearing stem. Q. petraea leaves are not very well lobed, and robur can be similar. This site looks good: http://www.cas.vanderbilt.edu/bioimages/pages/compare-oaks.htm

[johnw]

Anthony  - Q. robur we know as it is naturalized in the Annapolis Valley.  Likely the Acadian settlers brought acorns with them in the early 1600's.

We will have to have a close look at how the acorns are borne on these runty mystery Quercus.

johnw

[Robert G]

Hi John,

Just giving your pictures a quick look the second one looks like our Q. prinus, except for the acorn. The leaves of Q.prinus are somewhat distinctive and seeing the leaves when they come out would quickly tell you that it was not that.

Also we are assuming that the Q. prinus in the Arboretum here is what the records and label say. Not always the case, but in form and bark they look similiar. I will take a walk in the Oak collection to see if anything stands out.

Robert

[johnw]

Robert  - My guess is we have probably seen the leaves sometime in the distant path and would have remembered unusual prinus leaves.   The barksplit tells me it is not an eastern NA species - unless it was hit by lightening, unlikely as there are tall red oaks nearby.  Let me know if you come across anything with this strange habit. Appreciated.

johnw