Manitobans write the book on ideal Prairie trees

Columnar poplars have been a favourite for many years for narrow-space locations along fence rows and in small gardens. The older varieties are not suitable for our urban yards because of their limited lifespan and propensity for disease.

I recently met with Wilbert and Philip Ronald, owners of Jeffries Nurseries, located just east of Portage la Prairie on the Trans-Canada Highway. Jeffries Nurseries and other nurseries affiliated with its operations have introduced more new selections of trees into Manitoba than any other commercial nursery over the years. Wilbert recently gave me a detailed tour of the various tree nursery growing stock and has been hard at work over many years developing a very large number of new hardy tree species. I was privileged to examine their vast inventory of existing trees and new trees that are in the early stages of development.

The Ronalds have recently produced a full-colour illustrated book — Trees for Northern Landscapes. This wonderful book includes hundreds of tree selections for those gardeners and property owners who want to replace or augment trees in their properties and gardens with trees that survive in our hardiness zone. It is published in Canada by Friesens. Details of its availability can be obtained by email from Jeffries Nurseries at jeffnurs@mys.net. You can also get it directly by visiting the nursery.

With an increase in new residential properties in Winnipeg, the availability of land to establish trees has become an issue for many people. During my tour with Wilbert, I was struck by the large number of newer varieties of columnar trees now available for properties where space to plant trees is limited —especially new varieties of columnar poplar trees.

There have been ongoing problems with older, established varieties of columnar poplar trees this year, but I am pleased to report one of the newer, faster-growing columnar poplars — Populous x ‘Jeffguard’, also known as Guardian Hybrid Aspen — has been shown to have a high level of disease resistance to bronze leaf disease. This tree is expected to grow up to a height of 12 metres with a mature width of three metres.

There are also new columnar, fire blight-resistant crabapple trees that have been developed by Jeffries Nurseries, which would also be useful for properties where growing space is at a premium. Purple Spire and Emerald Spire are recommended columnar crabapple trees. As crabapples, they have small-diameter fruits but are unlikely to have sensational spring flowering. Their real value lies as screening trees, which is an essential feature sought by many property owners. All of these columnar trees as described in this article are illustrated in colour in the Trees for Northern Landscapes book.

I was very impressed with the listing of cultivated oak trees that are hardy for our Prairie climate. Of particular interest is the unique Admiration Hybrid Oak (Quercus x jackiana ‘Jefmir’), which was found growing as a mature tree of about 25 years in age in Saskatoon. The parent tree is believed to be a hybrid between white oak (Quercus alba) and swamp white oak (Quercus bicolor). Neither of these two parent oak trees are indigenous to the Canadian Prairies, but they do occur naturally in North Dakota. The golden-tan colour of the foliage of Jefmir persists on the tree into early winter. This is very unusual for any oak tree growing in our area. People often tell me that they think oaks are boring, but being exposed to these hybrid oaks will change your mind. Incidentally, there is nothing boring about our indigenous bur oaks as many of the have the longest lifespan of any other tree species growing in Manitoba.

There are so many more interesting cultivated trees recorded and often colourfully described in this book. If you are an avid gardener, or if you are into developing highly interesting landscapes with trees, this is the book reference you must have. I guarantee you will not be disappointed.

Michael Allen M.Sc.F., RPF (ret’d) is a consulting urban forester, tree diagnostician and certified arborist. He owns Viburnum Tree Experts. He can be reached at 204-831-6503 or 204-223-7709. His website is treeexperts.mb.ca

viburnumtrees@shaw.ca