Native trees — easy and beautiful
Closing the season with a blast of vibrant colour
As October gardening winds down, we can truly appreciate the importance of choosing beautiful, trees for our properties — they prove their worth by closing the season with a blast of vibrant red, yellow, orange leaves. Let’s take a look at a pair of easy to grow, native trees that deserve to be planted more often.
White oak
The white oak is synonymous with strength and durability — it is rare to find one that has been windblown or damaged by ice, writes Gerry Waldron in his book, Trees of the Carolinian Forest. Because of its strength, white oak was the wood of choice for hand-hewn beams in historic southwestern Ontario barns.
Slow growing, but very longlived, the best white oak lumber is harvested from trees ranging from 100 to 300 years old. Waldron explains that even 300-yearold trees may have only lived half of their span.
White oak trees prefer rich, moist, acidic, well-drained loams in full sun, but they adapt to a variety of soil conditions including thin, dry soils. White oaks show good drought tolerance.
Quercus alba, commonly called white oak, is a large deciduous native tree. Growing an average 15 to 24 metres tall, (and up to 30 m in the wild), this tree begins with a pyramidal form when young, maturing into a substantial tree.
Insignificant yellowish-green flowers in separate male and female catkins appear in spring shortly after the leaves emerge. Leaves (10 to 25 centimetres long) have deep rounded lobes. Leaves emerge pinkish in spring, but mature to dark green. Variable fall colour ranges from dull browns to rich shades of dark red and purple.
White oak grows over much of eastern North America and is an important hardwood timber tree. The light brown wood is prized for furniture, flooring, interior trim, veneer and wine barrels.
In his epic book Bringing Nature Home, Doug Tallamy encourages people to plant white oak trees from seed. The trees are difficult to transplant once they reach a few feet tall, however, they are easy to germinate from seed. Tallamy and his wife have planted dozens of native trees on their property, all started from seed.
“Because these trees started from seed and not from a whip or a pruned transplant, their shapes are terrific. Best of all, they were all absolutely free. In this age of instant gratification, most people do not have the mindset for starting trees from seed, but after four short years, you would never know we had not spent several thousand dollars on our trees.”
Tallamy describes an interesting relationship between blue jays and oak trees: “Everyone knows that squirrels gather nuts in the fall and bury them. Blue Jays do the same thing. The advantage with Blue Jays is that they will bring seeds to your bare patch from a good distance away, you do not have to have a seedbearing tree on your property to benefit.”
A mature white oak is not only majestic, it provides a valuable food source for both mammals, birds and moths, butterflies and insects.
While this might discourage some homeowners from planting a white oak, remember that insects are bird food. Cavities in large oaks provide a home for many species of birds. Acorns are an excellent source of food for many birds, including woodpeckers and mammals like white tailed deer. Birds will also use oak twigs and leaves for nesting.
Interesting to note: White oak acorns produce a root in the fall; the rooted acorn does not send up a seedling until the following spring. This summer, I discovered several oak seedlings in a quiet corner of the garden. I suspect our local blue jays saw the need for an oak tree and took matters into their own hands. I’m going to keep an eye on the seedlings over the coming year and then move them to a more favourable spot.
Black gum
I was first introduced to this charming tree on a tour at Niagara Parks Botanical Garden, and I’ve been under her spell since that day. Native to our Carolinian zone, the black gum (Nyssa sylvatica) offers some of the best fall colour in the garden. Black gum trees are not always available, but seek them out — they have a deep taproot which makes large specimens difficult (or impossible) to transplant — buy a small tree and let it grow.
Easily grown in average, medium to wet soils in full sun to part shade, black gum prefers moist, acidic soils, it will tolerate poorly-drained soils and can even grow in standing water. On the other end of the spectrum, it tolerates some drought. No serious insect or disease problems.
Black gum, also goes under the names sour gum or black tupelo, is a slow-growing, deciduous native tree which occurs in a wide range of soils. It features a straight trunk and rounded crown (more pyramidal when young) and typically grows 15 metres tall, but occasionally to 24 metres tall.
Although flowers are not showy, they are an excellent nectar source for bees. Flowers give way to oval, half-inch long fruits which are technically edible but quite sour (hence the common name). Fruits mature to a dark blue and are attractive to birds and wildlife including fox, deer, raccoons and opossums, and birds such as robin, mockingbird, thrush and woodpecker.
The black gum excels as an ornamental shade tree for lawns or street tree. It also grows well in moist woodland gardens or naturalized areas or in low spots subject to periodic flooding. Although slow-growing, give it plenty of room for future growth.
It is resistant to air pollution, salt, heat and drought. It has exceptional fall leaves — one of the best trees for brilliant red and orange fall colouring.
Gerry Walden says that black gum is a tree with so many good qualities, that its absence from the cultivated landscape defies reason. The Royal Horticultural Society has recognized the black gum’s merits with three awards.
Now in its fifth season in our garden, our young black gum has settled in and started to spread her graceful branches above our little patio. She’s just winding down for the season, the leaves turned to liquid amber overnight — the vibrant reds will be here to welcome the first days of November.
Be sure to get outside and enjoy the fall colours this weekend. If your garden could use a blast of fall colour, you might consider the white oak or black gum tree — these native trees are excellent choices for habitat gardens.