Every year, our city’s large population of Siberian elms creates a ‘snowfall’ in late May when mature seeds blow into gardens and every nook and cranny.
These large shade trees are tough and fast-growing, likely the reason so many were planted in earlier days. Part of their toughness is due to their drought-proof, deep taproot. It enables them to grow in dry, natural landscapes as well as irrigated gardens.
Each tree produces ‘millions’ of flat, dime-sized, off-white seeds which germinate readily.
It’s common to see them growing in awkward places (inside hedges, in cracks in sidewalks, against the foundation of a house) as well as flower beds.
Siberian elms can grow more than five feet a year. The taproot grows as fast, or faster than the top, making it difficult to dig out even when young. If any root is left in the ground it will re-sprout.
A good way to get rid of a larger tree is to girdle it between late spring and mid-summer. This means just removing a section of the outer layer of bark around the circumference of the trunk which deprives the tree of nutrients and should cause death in one to two years. Once dead, it can be cut down.
Cutting down a live tree does not kill it. It re-grows from the roots.
Other drought-tolerant tree seedlings to watch out for and remove quickly are Tree of Heaven (easily recognized by the stinky smell of leaves and branches when rubbed) and Russian olive. These and the elm are considered invasive.
In our irrigated landscapes, maple seeds germinate well and can grow quickly in the same difficult places the other tree seedlings populate.
If you have squirrels in the neighbourhood, as I now do, you may find walnut, oak or hazelnut seedlings in your garden beds.
Images on the Internet are helpful to identify any of these tree seedlings. Dig out as soon as spotted to avoid future difficult or costly removal.
The Kelowna Garden Club will sponsor a presentation by author and educator Sara Williams on Thursday, May 29, 7 p.m., in the Okanagan College campus theatre (Student Services Building).Admission is free.
And the Okanagan Xeriscape Association will host a book signing event with Williams on Friday, May 30, 10 to 11 a.m., at the unH2O Xeriscape Garden in front of the H2O Aquatic Centre, 4075 Gordon Dr.