Blue Beech

(Question)

Hi, I recently removed a dying tree in my yard and the city of Toronto required me to plant a blue beech tree as replacement. I know little about blue beech, so I did a little research online. However, the information I have found is quite confusing. Some websites say it’s also called American hornbeam, or ironwood, or hop hornbeam, which can grow very big. Some say it belongs to the birch family, and is a small tree that grows only 6-8 metres in Ontario, with a low spreading canopy. Since I have a small yard, I need to decide where to plant this tree based on its mature size, as well as sunlight requirement. I’m looking for some help to find more information about this tree.
Thanks!

(Answer)

Thank you for your question to the Toronto Master Gardeners.

You are right that Blue Beech (Carpinus caroliniana) is in the same family as Birch (Betulaceae) but in a different genus (Carpinus) altogether. Distant cousins, if you will.

The University of Guelph Arboretum is an established Ontario research facility. Its website calls the Blue Beech a small tree, and reports it does well in damp conditions, which are typical of our Carolinian forests.  As an understory tree, it can take the shade of taller, wider trees.

Here are description, conditions, and planting tips from Ontario’s Ministry of Environment and Energy:

” Size: Up to 8 m tall
Moisture: Prefers moist and can tolerate seasonal flooding
Shade: Can tolerate full shade, and full sun with ample moisture
Soil: Prefers rich, well-drained soils
Blue beech is best transplanted as a young, container-grown tree. Before mulching, you can layer 3 cm of mature compost in a wide ring around the tree on poorer soils. Blue beech is useful for naturalized understory planting but is also adaptable to urban sites and can even be used as a pruned hedge once established.”

It would be unwise to pile soil or mulch against the tree’s trunk in what we refer to as “the cone of death.” According to Trees of Ontario, “blue-beech wood rots quickly when left in contact with soil.”