When was the last time you really looked at a tree?
One of Marc Wolf’s vivid childhood memories is of doing just that: walking around his New Jersey backyard with a tree identification book when he was maybe 8 years old, exploring the towering individuals around him.
It wasn’t until decades later that he began closely examining trees again, after an education and a 30-year theater career, complete with an Obie Award, followed by a second education, in horticulture. But now the trees are on a 2,400-foot-high Catskills peak in Tannersville, N.Y., where Mr. Wolf is the executive director of the 178-acre Mountain Top Arboretum.
The trees of his current fascination are not the obvious show-offs of suburban backyards or parks. Their beauty is not the insistent, look-at-me sort that a pink-flowered crab apple or a flowering dogwood possesses.
They’re not the biggest trees, either — not the 70-foot-high red oaks or sugar maples, whose presence among the giants of the Mountain Top landscape is hard to overlook.
His current list embraces subtler choices, “native trees for the observant,” he said. “Trees that once you know and love them, make you pause and spend more time with them” — as he does, and wants us to.
“Gardeners are often focused on perennials, annuals and shrubs,” Mr. Wolf said. “And then, on the other end, on the canopy trees. But there is this other layer in the forest, and at its edge.”
Momentarily, many of the best trees of all sizes will be showing off, coloring up for visitors to the arboretum, where the gardens and trails are open every day from dawn to dusk.
Mountain Top’s trees are on display indoors, as well: 21 species were incorporated into the artisanal timber-frame education center completed in 2018, and seen in the arboretum’s 2019 book, “Twenty-One Trees,” photographed by Rob Cardillo. Each was selectively harvested from the grounds or nearby, to realize a design by Jack A. Sobon that did not specify standard processed boards of expected proportions, but rather the hand-hewed and organic.
“It’s a celebration of our native trees and our connection to them,” Mr. Wolf said of the 2,370-square-foot building, which is open Tuesdays through Saturdays, from 9 a.m. to 4 p.m.
In his five years at the arboretum, Mr. Wolf has come to appreciate a number of the 37 native tree species that grow on the property, and he recommended a few that are well suited to gardens.
A Tree of Many Names
Too many of our gardens have abrupt transitions, particularly at the boundaries: tall trees underplanted with lawn or another low ground cover, with no understory element in between. Layer-loving Mother Nature never designs that way.
Acer pensylvanicum, a great small tree for any shady spot, could be called upon to soften such incongruities and create a middle layer, Mr. Wolf suggested.
The first time you come across this maple tree it may not look much like a maple. Its leaves are so large, Mr. Wolf said, and they look especially big on a tree that reaches only 15 to 25 feet in height.
The tree has earned a variety of common names. Some refer to its foliage shape (goosefoot maple) and others to the texture of its bark (snakebark or striped maple, for the vertical white stripes most prominent on young trees). In recognition of the largest herbivore happy to dine on its bark, it is also known as moosewood.
Moosewood grows at the forest’s edge, or in gaps within the forest. As the tree matures, its white-striped green bark ages to reddish-brown with dark lines — also not very maple-like.
In larger maples, the flowers are high up; it’s easier to get a look at the dangling, chain-like ones of moosewood. Later, from July to September, you can enjoy its conspicuous samaras — the winged fruits characteristic of maples, again arranged in pendant chains. The tree’s light green leaves, translucent when backlit, turn luminescent yellow in fall.
Much to Mr. Wolf’s delight, sassafras (Sassafras albidum) is slowly making its way up the mountain. It brings with it many desirable traits, including fall color that rivals that of our native sugar maples. Its foliage, either mitten-shaped or with three lobes, ranges from yellow and orange into red and purple in autumn.
At the season’s other end, around leaf-emergence time, separate male and female trees produce flowers at their branch tips. The females’ are showier and, if pollinated, are followed in September by blue-black, bird-friendly fruits, each nestled in a gleaming red cup held on a red stem.
Sassafras is a host plant for the spicebush swallowtail and the tiger swallowtail butterfly, as well as certain moths.
And then there is its aroma. “Its leaves are Christmas-tree-meets-tropical-fruit,” Mr. Wolf said. “The twigs are strong root beer, to root-beer-meets-Christmas-tree.”
Sassafras can grow to 60 feet high, although it is more often around 30 feet high or shrubbier, if allowed to have its way with a space. It wants to form a colony, with root suckers that emerge insistently and must be dug out to urge the tree to grow in a single-trunk form.
Two Small Trees for Informal Hedges
Mountain Top Arboretum is not a place where formal hedges would look at home, but sometimes informal outdoor spaces want some definition — if in a much looser style, without the shearing.
Mr. Wolf has two possibilities to suggest. Both are small native trees or large shrubs, depending on your perspective.
One idea for an area in sun or partial shade came from a 30-foot-long row of pagoda dogwood (Cornus alternifolia) that he saw beside a home nearby. Its species name, alternifolia, for alternate leaves, notes its distinction among dogwoods. Members of the genus typically hold their leaves in pairs opposite one another along the stems, but not this one. Its branches are decidedly horizontal, and tiered — hence the common name.
Clusters of pollinator-friendly, white spring flowers are followed by blue-black fruit held on red stalks or pedicels. Look fast, before the birds devour it.
In fall, the foliage turns a soft purple-maroon, making it a true four-season plant.
“It would be just as great in a shady backyard of a brownstone,” Mr. Wolf said of the pagoda dogwood, which can reach about 20 feet high.
His second suggestion — a more familiar one, perhaps — is the pussy willow (Salix discolor), which will grow to some 15 feet if left unchecked by pruning. In a sunny spot in his home garden, Mr. Wolf has a willow hedge in progress.
For gardeners with a moist spot, this one is a contender, as even wet soil is no problem for it.
The plants are either male or female; the male will produce catkins that are more ornamental — and loaded with pollen. Pussy willow offers nectar and pollen to a wide range of early awakening insects around March, a time when little else is in bloom, and is host to various Lepidoptera, including the mourning cloak butterfly.
Which Hornbeam or Ironwood Is It?
Two trees in the birch family (Betulaceae) have caught Mr. Wolf’s attention as promising, although little used, garden candidates. Both are native to the Eastern forest understory and can reach 25 to maybe 40 feet. To confuse things further, both have the word hornbeam in their common names, and they also share one of various other common names, ironwood.
Carpinus caroliniana is best known as American hornbeam, blue beech or by the evocative name musclewood (for the muscular fluting in the wood of its smooth, gray trunk and larger branches).
“We have planted a lot of these at the arboretum, and their fall color is variable, from a beautiful red to orange to purple, or just a simple golden yellow,” Mr. Wolf said. “If you’re shopping for one, consider doing it in fall, specifically to see its color.”
He is curious about its potential as a pruned hedge. European hornbeam (Carpinus betulus) is famously used as such, and he has read that the native could be treated the same way.
Ostrya virginiana, or American hophornbeam, has distinctive clusters of puffy seedpods from summer into fall, resembling those of hops. Catkins develop in the fall and remain through winter; with the tree’s vertical strips of curling, shaggy bark and handsome structure, that makes it appealing year-round.
These and the other trees are at the center of the Mountain Top mission: combining horticultural excellence, environmental stewardship and education — as well as a celebration of the pure pleasure of the place. We are encouraged to come, wander and watch, taking ideas home from this distinctive spot, where frost arrives three weeks earlier than it does just six miles down the mountain, in Palenville, N.Y.
The first acts of spring start three weeks later here, too.
“People often think of landscape design or gardening as a painting,” Mr. Wolf said. “But I think it’s more of a theater: You move through it, and things are always changing. There are sounds and smells and textures, and a story to it.”
Margaret Roach is the creator of the website and podcast A Way to Garden, and a book of the same name.