Russian olive is not a common shade tree in my area. It prefers poor soils and does well in waste places and less-than-ideal growing sites. It has nice silvery-gray-green foliage, which makes an interesting accent in a mixed ornamental planting, or as a specimen in areas where other things won’t grow. There is a planting a long Deerfoot Trail north in Calgary, on an inhospitable windy slope, that seems to be doing well.
The Russian olive tree tends to develop self-destructive branch structure if left to its own devices, so proper structural pruning is necessary for the first few years after planting.
I generally avoid planting this tree for four reasons:
1) In 2015, a reasearcher in Lacombe suggested that Russian olive be considered and invasive species that is likely to choke out streambank habitats. I don’t want to contribute to that problem;
2) the trees are thorny and a nuisance to maintain;
3) they are prone to a fungal die-back disease that can result in disfigured, unattractive trees;
4) I prefer using silver-leaf willow, as the foliage is very similar, and the plant is less susceptible to disease.
The nicest Russian olive I ever saw was on a corner lot, on a busy road in Red Deer. The owners removed the tree because a neighbour said it was too close to the foundation, which was nonsense. The following year they planted a new Russian olive in the same spot! Sometimes its best to call an arborist for advice.
Anytime of year for up to 10% pruning of canopy, or deadwood removal. For heavy pruning, dormancy is best (late October until early April).
If you have a chance to train this tree from planting, train as a central-leader standard, with well-spaced scaffold limbs. I normally get called in to look after very mature and neglected specimens, where my options to improve branch structure are limited. In that case, I remove dead, diseased, and damaged braches, reduce width and provide branch clearance over walkways and away from buildings, as required.
Generally, not suitable for crown reduction, and if planted in a suitable location, unnecessary. I had one specimen in Leduc that we sheared by hand each year, at the request of the client. It was a big, silvery ball, but not overly attractive. She since removed the tree. A well-structured, natural form is best for Russian olive.
(c) 2017 Shane LePage, Wild Rose Garden & Tree Service Inc., Red Deer.