Can you please help identify this plant thank you?
An answer to your question posted a few days ago by another Toronto Master Gardener is below.
“I believe a bird or rabbit has gifted you with a couple of chokecherries (Prunus virginiana).
It’s is an attractive tree that can become quite large, has lovely white flowers in spring and the berries, which you have photographed just before they ripen to a reddish black, are attractive to birds but can be used to make excellent jelly!
Carleton University’s Cowling Arboretum has a great fact sheet about them with pictures.
Common and glossy buckthorn are invasive species that are often confused with chokecherries, but the berry racemes and alternate leaves in your photo are more like chokecherries. Here is another fact sheet that compares the three species and the (confusingly common named) chokeberry.
Hope this information is helpful.”