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Small Trees
Yearbook 1991 By: Brian Douglas Back to the web versionSmall Trees
by
Brian Douglas
Dominion Arboretum Of Canada
It was a beautiful sunny fall day, the air was crisp and inviting for one of those slow leisurely walks, the type of walk where you observe and categorize your thoughts through all your senses. It was on one of these walks that I noticed many houses in an older project with gigantic trees consuming every bit of available front lawn. Drooping evergreen boughs or massive gatherings of leafless branches filled every yard.
The days of majestic building lots, with ample room to create and reflect an individual's horticultural taste and style, have been replaced with small, uniform parcels, with restrictive borders. People must now find plants which will retain a much more compact form without constantly needing pruning back year after year.
Enter the world of small trees. Over the years, through careful breeding, research stations have created forms of trees and shrubs, designed to be more in scale with these confined spaces. Unfortunately, nurseries have been slow to promote newer plants, and are remaining with tried and true varieties.
By researching available plant sources, I have compiled a short list of material suitable for the smaller property.
Acer ginnala 'Compactum' - Dwarf Amur maple
Here is a tree that has all the splendor of maples while keeping a much lower profile. After about 40 years this tree should be no more than 15 ft. tall. It has nice summer leaf color with a brilliant display of color in the autumn months. It's hardiness. zone is 3a-6b with no real problems and little maintenance required.
Caragana arborescens 'Pendula' and 'Walker' - Peashrub
These particular plants serve a very useful purpose in the garden. Since they are grafted onto a single seedling stem, they retain a miniature form. Because of these grafted forms, varying heights may be bought to suit any location. Both have a very weeping habit but 'Walker' has very finely divided leaves and is almost fernlike. Both forms are very hardy in zones 2a-6b.
Crataegus succulenta - Fleshy Hawthorn
This tree will grow to 15 ft. at maturity and like many fruiting trees is a pleasant addition to a small property. It has an abundance of flowers in springtime which later develop into 1/2" thick glossy red fruits. The only drawbacks are numerous stout 2 in. thorns. This variety of crataegus is also quite hardy with a rating of Zone 4.
Malus 'Uset' - Uset crabapple
This is a particularly good tree which will attain a height of about 15 ft. at maturity. This variety of malus blooms at a much younger age, with rose colored flowers. Its fruits are maroon colored and quite small, about half an inch in diameter. It has purplish red colored leaves which makes for nice summer color. This tree has very good to excellent disease resistance to scab, cedar apple rust, and fireblight with a moderate resistance to mildew. This malus is quite hardy to Zone 4.
Viburnum prunifolium - Black Haw
This plant will reach a height of 12-15 ft. after 25 years. Its flowers are white, small but numerous, in clusters 2-4 in. across, usually fairly showy in late spring. The leaves of this plant have a leathery texture, with finely toothed edges. This viburnum has pale green fruit, ripening to blue black by fall, adding interest to the colorful autumn foliage. Pruning is seldom necessary, except for initial training of tree form. This viburnum is hardy to Zone 3b.
The care and maintenance of these plants is no different from their much larger counterparts but methods of plant care have changed greatly in the last few years. There are many new books available which update many tree care practices. Look for Arboriculture by Richard W. Harris (Prentice-Hall), A New Tree Biology by Alex Shigo (Shigo and Trees Associates) and Tree Maintenance (5th edition) by Pascal Pirone (Oxford University Press)
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