Report by Nina Shoroplova

On Friday, August 4, twenty-four botany enthusiasts joined Nina Shoroplova and Caroline Penn for a tree walk in the south half of Shaughnessy Park. We started our walk from the Osler Street entrance to the park where there are two maples.

We started by telling the differences between the sugar maple (Acer saccharum) on the north side of the central path and the Norway maple (A. platanoides) on the south side. It’s important to know some of the ways to differentiate between the tree that’s on our country’s flag and provides us with maple syrup that is growing on the north side and the tree that many consider invasive and is growing on the south side.

Walking west, we identified, learned about, and appreciated the trees one by one, admiring leaves, trunk, branching, roots, and more. The following is only a partial list of all the trees in the park.

• A sourwood, Oxydendrum arboreum – come back in the fall to enjoy the brilliance of its colours: scarlet leaves and green leaves, and strings of white seeds where once there were strings of bell-shaped flowers.
• Another sugar maple with a massive trunk, muscly branching, and spreading roots.
• A deodar cedar, Cedrus deodara, one of the three true cedar species growing as ornamentals in Canada.
• Three trees in the Aesculus genus, two being horsechestnuts and the other being a buckeye. We were able to tell them apart by their fruit.

• Two Lawson falsecypresses, both of them dying, more than likely from Port Orford Cedar root disease caused by Phytophthora lateralis. Being connected through their roots, these trees are sharing the fungal disease that is killing them both.
• Yellowwood, Cladrastis kentukea. We knew its wood is yellow because a high branch had recently been removed. The tree had not had time to heal itself.
• A coffin tree, Taiwania cryptomerioides. The common name might suggest the tree is well-armed and that is true, because its armature attacks anyone getting close, but in fact it is so named because its wood is used in its homeland of Taiwan to make coffins for grand funerals.

• Oriental spruce, Picea orientalis, was next. The needles of this species surround the twig and are gentle to touch. Both pollen cones and seed cones (of this year (purple, green, and pitchy) and of last year (brown and dry)) were visible on the tree. 
• A young, female black tupelo tree, Nyssa sylvatica, offered some fruit, which helped in its identification. This is a dioecious species—it takes two to tango.

Twice, we escaped from the heat of the sun inside the broad and cool canopy of one of the beeches. Inside, the leaves were green and I was surprised to see that outside, the side facing the sun, they were not as dark as I have seen them before, such as in this photo I took in June 2020.

• We agreed that the coast redwood, Sequoia sempervirens, was looking unhappy, missing the moist fogginess and rains of its native terrain in Oregon and California.
• Walking back to our starting point along the central path, we saw the circle of large-leaved lindens, Tilia platyphyllos, and the centre dominated by a couple of Pontic rhododendrons and an August-tired Eddie’s White Wonder dogwood.
• Our walk ended at the young Kentucky coffeetree, Gymnocladus dioicus. This tree grows leaves that are bipinnately compound rather than simple or even pinnately compound, and bark that is rough and scaly.