Would you please let us know if you can identify a young sapling. We live in Etobicoke (West Toronto), Ontario, Canada. The leaves are heart-shaped and is growing quite rapidly like a soft-wood species. We did take the tree to Sheridan Nurseries and they could only indicate it was an ornamental tree of some kind.
Thank you for your help.
Thank you for contacting Toronto Master Gardeners.
It can be very difficult to identify trees when they are this small. With larger trees you can look not only at the leaf shape but also the bark, flowers, fruit and structure of the tree. At this point only the leaves are are available for use to make this identification.
The leaf shape it points towards a tree in the Betulaceae family. This family includes Alders, Hazels, Hornbeams and Birch. Looking through different resources, the leaf most closely resembles some Alders and some Birch species. As the tree grows and the bark matures and it flowers it should become more obvious which species you are dealing with. Alders show their catkins in the fall while Birch have theirs in the spring. Alders do start producing catkins at a very early age.
One clue may come from where this tree originated. Did it show up in your yard or somewhere else? looking at what other trees are in the area will help to narrow down the possibilities. The seed most likely originated some where near where the sapling was found. Alder are known to reseed easily so chances are that is what you have.
Alder and Birch do prefer moist soil so you will need to monitor the tree closely when you plant it to ensure it has enough water.
There is an invasive Alder in Ontario called the European Black Alder, Alnus glutinosa, which does not have the pointed leaf like your tree, so I am fairly sure that is not what you are dealing with.
The links below are for a site that you can use to look up the different alder and birch in Ontario. It is hard to find an exact match but you may also be dealing with a hybrid instead of the native species. Good Luck and the answer should become clear when the catkins arrive.