Visiting your local shopping mall can be a fun green experience. This past weekend I dropped off my son at a gym for a friend’s birthday party and headed to a nearby mall Starbucks. While my wife enjoyed her first latte macchiato, I was more interested in the parking lot trees.
First, the good news.
The newly planted Sorbus aucuparia ‘Rossica’ (Russian mountain ash) is a beautiful specimen tree suited for cooler climates. It has ash-like leaves but actually belongs to the rose family. It’s a pyramidal tree with lobed leaves that turn orangey-red in the fall. In mid-spring white flower clusters emerge; and in winter we get clusters of red berries. The berries attract birds and they always remind me of mountain ashes.
Sorbus berries
Sorbus aucuparia ‘Rossica’
Sorbus aucuparia has year-round appeal and likes full sun which it will get in the middle of a mall parking lot, plus plenty of reflective heat as the pavement heats up.
Now, for the bad news.
Take a closer look at the tree install. The fresh mulch is great for the tree because it keeps moisture in (soil water retention) but why the classic mulch volcano? Dr. Linda Chalker-Scott writes that piling mulch too high creates a dark, wet, low oxygen environment to which above-ground tissues are not adapted. Fungi love these conditions and are likely to infect the tree; pests can also use the moist conditions to enter the tree bark.
horrific mulch volcano
Do not create mulch volcanoes. Instead taper the mulch to almost nothing as you get close to the trunk. This creates a donut shape which protects the soil environment and above-ground tissues. Remember: donut shape!
Still thinking about mulch volcanoes, I picked up my son at the gym where young cheerleaders ran around in VAS t-shirts. My kind of gym! Vancouver All Stars.
