[CANUFNET] Elms and breakage

[Andrew Boyd via CANUFNET]

Hi Alison,
As someone who has been heavily involved in the work around Parliament Hill in Ottawa I can tell you that the predominant cultivar (clone) used has been 'Liberty' and not 'Accolade' (at least in the case of the elms planted adjacent to the US Embassy not far from the hill).  Like many elms developed in response to Dutch elm disease it seems they do have a tendency to form poor unions (in particular with included bark).  Ultimately of course this can lead to failure as the trees mature.
On another recent project in Ottawa this was also an issue for a number of 'Valley Forge' trees, none of which were over 15cm in diameter.  From what I could tell in this instance they were victims of their own success - growing so rapidly that pruning couldn't keep them in good form.  It sounds as though your clients are experiencing the same issue.

Andrew K. Boyd, R.P.F.
Consulting Urban Forester
IFS Associates Inc.
P.O. Box 13593
Ottawa, ON
K2K 1X6
Tel: 613-839-0101
Fax: 613-839-0114
www.ifsassociates.ca

From: CANUFNET [mailto:canufnet-bounces at list.web.net] On Behalf Of Alison Bond via CANUFNET
Sent: Tuesday, January 9, 2018 4:46 PM
To: canufnet at list.web.net
Subject: [CANUFNET] Elms and breakage

All:

At a conference in Quebec City I learned that much of the areas around the parliament buildings were being planted with Accolade Elm with good success.  After that conference we started incorporating elms into our street tree planting plans.  Accolade wasn't always available so there were often substitutions (Valley Forge, Princeton, Pioneer, Triumph.)

I have recently noticed that some of the elms (when reaching about 15.0 cm dbh) are starting to break apart and large branches are failing.  Many of these elms are vigorous growers and municipalities haven't been able to keep up with pruning to keep the form strong.

Has anyone else noticed this predisposition to breakage?

Thanks.
Alison


Alison Bond BSc MSc BLA   OALA  CSLA
Landscape Architect and Certified Arborist

ENVISION-TATHAM Inc.
115 Sandford Fleming Drive, Suite 200, Collingwood, L9Y 5A6
abond at envision-tatham.com<mailto:abond at envision-tatham.com> I  Tel: 705.445.0422  I  Fax: 705.444.2327  I  Cell: 705.994.2059 I   www.envision-tatham.com<http://www.envision-tatham.com>

This email may contain confidential and/or privileged information for the sole use of the intended recipient.  Any review or distribution by others is strictly prohibited.  If you have received this email in error, please contact the sender and delete all copies.


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.web.net/pipermail/canufnet/attachments/20180111/be4182b8/attachment.html>