It is at this time of year that I encourage readers interested in landscaping with native plants to visit the University of Maine Cooperative Extension office landscape in Ellsworth (Boggy Brook Road). Planted with woody plants and herbaceous perennials that are native to the midcoast region, this landscape has matured substantially since it was first planted. Many of the perennials were dug and divided earlier this year, each providing several offshoots for the annual plant sale.
It is a changing landscape through the year, beginning in early spring with the flowering of marsh marigolds in the rain garden. Done with flowering by the end of June, the ragged leaves of this summer-dormant plant will soon wither away. Native iris, penstemons and campanulas take center stage during July.
The pagoda dogwood has finished flowering and its fruits are forming. Ripening in early autumn, these purple-black berries will be a feast for songbirds, as will the deep red hips of the Virginia rose, Rosa virginiana, now in full flower. In this same section of the landscape, highbush blueberries are also ripening fruit, an early treat for robins and other thrushes.
Summer visitors can experience the fragrant foliage of two native shrubs, sweet fern and bayberry, and the summer-long flowers of two other native shrubs, meadowsweet and steeplebush, then return in autumn to enjoy the blooming of exuberant perennials like native goldenrods, joe-pye weed, and helenium.
This landscape is also home to one of the lesser-known native pines, jack pine (Pinus banksiana). In my mind, this is a rugged and handsome garden tree, better suited to the small garden than the larger native pines. It grows from 15 to 50 feet in height, depending on soil type, with a narrow, open, irregular-conical form, each tree unique in character with windswept recurving branches and dead lower limbs that persist for years, features that reflect the harshness of Maine’s coastal landscape where jack pine grows wild. The lower limbs die from being shaded by upper limbs and, indeed, jack pine must have full sun to thrive.
The short needles are sharp-pointed, stiff when mature, somewhat twisted and yellow-green; the cones asymmetrical and curved, often smooth or with tiny prickles, and pointing forward, toward the tip of the branch. A large proportion of the mature cones remain on the tree, tightly closed, for up to 20 years. From time to time, some of these old cones open and shed their seed, resulting in a mixture of open and closed cones on the same tree, but the majority of cones remain closed until fire consumes the forest. Then they open in response to heat and release their seeds, some of which survive to ensure regrowth of the forest.
Highly tolerant of drought, jack pine grows best in course sands and gravels and is intolerant of clay soils. It is also intolerant of alkaline soils, growing best in highly acidic to slightly acidic conditions (pH 4.6-6.5). It is salt resistant but intolerant of soil compaction.
When might you consider using this pine in a landscape design? Of course, for sites composed of acid, sandy soils, jack pine would be a good choice. Another good reason is jack pine’s wildlife value. Stands of jack pine provide nesting sites for several species of song birds as well as ground nesters, including common nighthawks and vesper sparrows. As urban sprawl and other human disturbances continue to destroy natural stands of jack pine, using them in managed landscapes may become essential for the survival of these and other bird species.
I am pleased to say that I planted this jack pine in this landscape, siting it on a berm above the rim of the rain garden, certainly not in its natural element, and because the soil there was clayey, I set it high, its uppermost roots barely covered.
There were skeptics, one in particular, that predicted the sure demise of the tree. It had the characteristic contorted habit of coastal pines, as though it had, in its young life, already seen its share of windstorms. I believe this is what raised the hackles of the skeptic, this touch of roughness in an otherwise orderly, smooth landscape.
It did not fit the design, this rugged, little tree, a hobo at the dinner party. Stick around, I said to the skeptic, it gets even better with age.
Last year the tree fell victim to a needle rust fungus that made it look very shabby for much of the summer. No doubt this provided a touch of vindication for the skeptic, giving hope, perhaps, that the tree was in permanent decline. But this year each branch has put on six inches of new growth, soft bright green needles surrounding a new crop of cones. No sign of the fungus. As anyone who lives with this tree in its native coastal habitat will tell you, it is a tough, resilient species.
Like many of the people who live with the harshness of Maine’s coastal environment, jack pine, with its windswept growth habit and persistent dead branches, has a rugged sharp-edged character. And like such people, that character can only get better with time. Take a drive out Boggy Brook Road in Ellsworth and see for yourself.