I’M ALWAYS LOOKING for more places to tuck native plantings. My current mission is along my property edges, where I’m adding a more complex layer of shrubs and small trees adjacent to the big old canopy-level ones to increase habitat for beneficial insects and birds, in particular.
I’ve been turning to Marc Wolf of Mountain Top Arboretum for suggestions, and now we want to share some of our ideas with you for garden-sized native woody plants to enhance the diversity of your landscape.
Marc is director of Mountain Top in the Catskill Mountains of New York, 178-acre public garden that’s open every day of the year, and where managing native plant communities is the focus. He has a particular appreciation for small native trees that we too often overlook, and we talked about some of his favorites, and also a palette of native shrubs to delight you and the bees and the birds.
Plus: Enter to win a copy of “Twenty-One Trees,” a book with portraits of the arboretum’s species and the education center built from wood of some of them, too.
Read along as you listen to the Oct. 4, 2021 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on Apple Podcasts (iTunes) or Spotify or Stitcher (and browse my archive of podcasts here).
native shrubs and small trees, with marc wolf
Margaret Roach: Hi Marc, I’m so glad to talk on this fall day [laughter].
Marc Wolf: Hi Margaret. Thanks so much for having me. Yeah, it’s such a great… It’s like the earth is celebrating fall. I mean, it’s cold and clear and beautiful up here, and the leaves are already changing color up here.
Margaret: So you say “up there.” You’re at 2,400-foot elevation, is that correct?
Marc: Yeah, 2,400 feet in Tannersville, New York, which is in the Catskills. Which is near Hunter Mountain if that’s helpful to people.
Margaret: Yeah, for their GPS [laughter].
Margaret: So before we get started talking trees and shrubs, I wanted to ask you for a quick sort of introduction to Mountain Top Arboretum, but also to say that you have this not-so-long-ago-built education center and built from many species of wood from many trees from around the property and nearby. You did a book about it called “Twenty-One Trees,” and about those 21 trees. And we’re going to have a giveaway of a copy of that beautiful book with photos by Rob Cardillo. So tell us what is Mountain Top, briefly? [Above, the education center; photo by Rob Cardillo from the book “Twenty-One Trees.”]
Marc: Mountain Top Arboretum is a 178-acre public garden. And it started in 1977 with 6-1/2 acres, and over time it’s grown. We’ve become more native plant focused over the life of the arboretum. Especially as you’re talking about the new education center is really a celebration of native plants because we went through our forest and some generous neighbors who donated some trees too. We have 21 different species of native trees that are represented in this beautiful timber-frame structure. And the floors are also from trees from our forest.
And then that sort of bleeds out—that was sort of the inspiration for the landscape design that we did with landscape architect, Jamie Purinton. And so the site itself, the 1-acre site we sit on, is designed with rain gardens and plants native to the Catskills—rain gardens, woodland edges, and bedrock outcrops are the three plant communities. [Below, part of the arboretum in fall; photo by Rob Cardillo.]
Margaret: We recently did a “New York Times” garden column together, which was fun. And we focused on some of those plants that you grow and love there. I think you have 37 species of native trees on the property, is that right? Do I remember that number?
Marc: Yeah. Actually 37 species of trees that are native to the Catskills.
Marc: And when we talk about the Catskills, there’s a blue line that New York State created. It’s called The Blue Line [laughter], because on the maps, it’s a blue line—and it’s such an artificial line for us. But that’s what we used to sort of what we wanted to… We’re doing a native tree trail also; we’re working on that. So what we call native to the Catskills is within the blue lines.
Marc: So there are trees that are native on our site that have been planted over the years that are native to the Northeast, but that’s not in the 37, just to be clear [laughter].
Margaret: You’re right. To be clearly unclear. Yeah. Well, and the whole word native is a confusing word. And so just for those who are listening, who are in many other places, a lot of what’s native to whether the Catskills or to new England or to New York State, where you and I both live and garden—many of those things, and many of these we’re going to talk about today are native over a wider range, so Eastern quarter of the country, the Eastern third or even half, and some even farther afield that we’re going to mention today. Some go down into Texas and some go out to Montana. So I’m going to give links with the transcript to range maps, the native range maps of the plants we talk about so that people can look and see, hey, is this appropriate? Just to add to it.
So, in that recent “New York Times” column we did together, we first sort of talked about some small native trees that gardeners mostly overlook in favor of maybe flashier, flowering, spring crabapples or whatever. And I know you wish we’d kind of slow down and notice a couple of these subtle beauties, like moosewood, for instance. Can you tell us about that? [Moosewood bark, below, photo by Rob Cardillo; Marc Wolf with moosewood farther up the page, too.]
Marc: Sure. So yeah, these are trees that when you’re driving by, they might not shout at you, but I think we’re all thinking of how we reconnect with nature more. And I think we just need to spend a few more minutes looking at what’s growing on our property, or on our street. So striped maple is a tree that is often overlooked. It is a tree of moist, rich, cool areas. So it may not do so well say down in New York City. But it can get up to 35 feet, maybe even 50 feet in the forest, with beautiful striped green-and-white to yellow-striped bark.
And unlike the other maples, its flowers are quite, well, large for maple. They’re about one inch and they dangle down in chains in the early spring. They’re greenish-yellow, and you’ve got to look for them, but a 1-inch flower isn’t too small and they’re really beautiful.
And then when they fruit with the samaras that are typical of maples, they are also hanging down in these chains that persist for quite a long time. I’m looking out the window, a few striped maples now, and those samara are still hanging on. And then the fall color—this one hasn’t turned yet—is like a light butter yellow. And the leaves are… Oh, we didn’t talk about the leaves yet. They’re so large, and it’s also called goosefoot maple, because its leaves are like big goose feet. They’re really, really big leaves, bigger than the maples we’re used to, like sugar and red maple.
So the way they catch the light is gorgeous. And then in the fall they turn a yellow, which just lights up when they’re backlit by the sun. It’s a beautiful tree.
Margaret: So that’s Acer pensylvanicum, and it’s a very common tree along the woodland edge where I live and into the beginning of the forest around me.
Marc: And people think it’s weedy. No, it’s not. There are people who will argue with me [laughter]. I love it, but it’s not this sort of statuesque tree. It’s great at the edge.
Margaret: Right. So another is the pagoda dogwood. People know Cornus florida, the flowering dogwood, and some of the other non-native Asian dogwoods, and some of the shrub dogwoods, like Cornus sericea and so forth, but the pagoda dogwood. What is it? Is it, I’m going to say the wrong thing, is it alternifolia?
Marc: Yeah, alternifolia, alternate-leaf dogwood.
Margaret: Right. Cornus alternifolia. And so just quickly, that’s another small one that is distinctive. Yes?
Marc: Yes. Well, like the flowering dogwood, Cornus florida, it has this very tiered branching, maybe even more tiered than the flowering dogwood, which is why it’s called pagoda dogwood.
Marc: So even in the winter, it has this really lovely tiered structure. Beautiful, typical dogwood, lovely green leaves. The flower is a cyme, I’m pretty sure, so it’s more of like a umbel-shape, like a flat umbrella-shaped white flower.
And important for pollinators, etc. And the fruit then is this blue-black, and the birds love it. So it may go fast.
Margaret: [Laughter.] Right.
Marc: The fruit is held on these red, like pinkish, bright red stalk. So even if the fruit’s gone, you really get this flush of red on the whole shrub. From my window at home, I have one that’s just growing naturally and it’s peeking out from the woodland edge and I can see it from, I don’t know, 50 yards away. I can see that red shining out. And then it’s got a really beautiful, like maroon-ish, purple-ish, reddish, fall color.
And I think in the article you mentioned that I had seen it near my house—I think it’s natural—growing naturally as a hedge.
Margaret: So like a row of them.
Margaret: Yeah. Not a strictly pruned hedge like a…
Marc: No. Right.
Margaret: ...not like boxwood. But lined up as a small tree, large shrubby-kind-of-stature hedge.
Marc: Yeah. And it’s not long-lived, and there is something called gold fungus that some of them get up here, but they seed it around a lot. So they’re going to proliferate around not in a really aggressive way, but if you have one, you may have more—and once you know that really distinctive dogwood leaf you can put a little deer fence around the one that you see coming up and encourage another one.
Margaret: Right. I know that you’re a lover of gray birch. It’s a little bit bigger, but give us just a quick lowdown on why you love gray birch so much.
Marc: Yeah. So I learned about gray birch from Darrel Morrison, when I was working with him on some projects. It’s such a great small tree for a grove. There’s a really important book that really everybody should read. It’s a short book called “American Plants for American Gardens” [affiliate link] written in the 1920s by Edith Roberts and Elsa Raymond, who were at Vassar. And they talk about different plant communities in the book. So it’s really wonderful for designing and getting ideas. But they have a whole chapter on the gray birch community.
And it’s a small tree, it’s Betula populifolia—and populifolia means it’s got leaves that sort of shimmer in the wind like trembling aspen.
A nice white bark, but it has blacker patches on it under the branches, blacker than say the paper birds. So in the winter, it’s almost like I’m stealing this line from “American Plants for American Gardens,” but it’s almost like an etching against the snow. And it’s a pioneer tree, so it’s really great on tough sites.
And I was talking to you earlier another time where… My Mom just sold her house in Northern New Jersey. And she had huge oaks that the new owners cut down. I think people are scared of the weather now and unpredictable nature. So a lot of these small trees that we’re talking about, feel like, the gray birch feels like a bigger tree, but it’s not, and it won’t get so big that it’s going to be intimidating near your house.
Margaret: Right. And like you said, a grove and that’s something that in certain spots that could be very inviting a sort of miniature grouping of these trees could be very inviting.
Margaret: And sometimes it’s hard to say whether woody plants are… Is it a large shrub? Is it a small tree [laughter]? So like shad (Amelanchier) or pussy willows (Salix) come to mind. And a lot of native shrubs are really having a moment now, or very soon. They’re fruiting up to feed migrating or resident birds. They’ve got fall foliage color.
And as I said at the beginning, a lot of the ones we were are going to mention I hope, they may be native where we are, but they may also be native over a wider range. So again, I’ll give some links to some range map so people can look them up, if they’re in the Mid-Atlantic or even the South, in some cases and farther into the Midwest and beyond. I’m a winterberry (Ilex verticillata) [below] and highbush blueberry freak. How about you?
Marc: Yes, totally [laughter].
Margaret: See. I just think you can’t get enough of those and the birds seem to agree with me.
Marc: Yeah. They’re both great, of course. But the Ilex verticillata, the winterberry, you have to plant a male, a few males around, also to get that fruit. Yeah, gosh, which one do you love more?
Margaret: Well, the winterberries, I think that’s a good point that you need like a male for every, I don’t know half a dozen or whatever females. I tuck the males away, not in a prominent spot. I mean, not too far away from the females, since I don’t want them to be front and center. But the blueberries seem to do their own thing and they have such incredible fall color. There’s really nothing like the red of blueberries in fall, do you think?
Marc: Yeah. And they’re just so much fun to eat [laughter].
Margaret: No, the birds get all mine.
Marc: Yeah. Oh, they grow naturally on my property. I have three different… I have lowbush and then sort of a medium lowbush and then the highbush. And I’m always finding them, they grow under power lines near me. They’re a really tough plant. Supposedly they’re finicky. Maybe they’re hard to establish, but acidic soil, sun, they seem to take a lot of moisture, too.
Marc: And really wonderful for a hedge with the fall color and beautiful green foliage—the highbush. Yeah.
Margaret: Yeah. I have them in some big groupings in some cases mixed in—the winterberries and the highbush blueberries, and also Aronia, the chokeberries. Do you have Aronia up there on the mountain?
Marc: Yeah, that’s a great plant. We have a lot of the Aronia melanocarpa and that grows naturally up here, too. We see it, if we’re not mowing an area say there’s a whole lowbush blueberry area of the arboretum and Aronia is coming up through there, the melanocarpa. It’s denser. It’s a great plant. I don’t really use a lot of cultivars, but there’s a great cultivar of melanocarpa called ‘Viking,’ which is smaller and it’s just like masses of these beautiful blackberries in the late summer. And then the Aronia have great fall color, but I was looking at the red chokeberry yesterday.
Marc: Because we have that too. And I was thinking if you want a hedge—like privet hedges. I think of the great privet hedges like on Eastern Long Island, you can sort of see through them. They’re almost like a screen that you can’t see through, but maybe you can see through. And I think Aronia arbutifolia, the red chokeberry, would be a great replacement for that, because it’s not as dense as the black chokeberry and a lot of the hedge shrubs. So if you want an airier quality of your hedge, I’m thinking, I mean, we don’t have it that way, but I’m thinking that might be nice. It’s sort of more upright, I think, than the black, and has got a beautiful, glossy green foliage, the red berries are really striking. And there another cultivar, this one is ‘Brilliantissima,’ and that’s just a great sharp red fall color. Not too red. Just beautiful.
Margaret: The thing about picking native shrubs to use in your landscape whether for a hedge or as a sort of a layer below the canopy, an intermediate layer below your canopy trees or along the edge of the road or whatever, or just tucked into other beds, is that you can pick a range of fruit also that provides different nutrients at different times of year to different birds.
So like we were talking about the winterberry hollies and those are more oil-rich, the fruits. They’re not as sugary and so forth. And some of the fruits like Aronia, they don’t ripen until very late. They have a lot of tannins, speaking of Tannersville, a lot of tannins in the fruit. And so it’s very astringent and it’s not ready-
Marc: It’s really astringent. Yeah.
Margaret: Yeah. And it’s not ready till later. And so you can have a whole sequence of fruits with different nutrient values, some to fatten up those birds for the migration, or keep them warm in the winter. Some just to give them more of a burst of fuel early, you know what I mean? It’s great to sort of think about the different qualities of fruits as well. I love viburnums as well.
Marc: Oh my gosh.
Margaret: And we have a lot of native viburnums.
Marc: We have so many native viburnums. I mean, you could do 10 shows seriously on, the native viburnums [laughter].
Marc: There’s one that I only learned about it I think in 2014, I was on a field trip. I was an intern at Chanticleer, and I was on a field trip and we came across Viburnum lantanoides at a property we were visiting that was planted. And the reason that I didn’t know about it, and I think a lot of listeners may not know about it is again, it’s sort of like the striped maple, but even more—it’s a cold, moist plant. I mean, it grows in the ravines up here. So there’s cold water running down the ravines and there’s mist coming up cold in the mornings.
In the spring, it flowers really early. The first time I saw it up here, there’s a lot of it up here. It almost looks like a Hydrangea flower. It’s quite large. And it’s got the sterile flowers, like a hydrangea does that are bigger. And then it’s got these, the inner fertile flowers. [Above V. lantanoides flowers; photo by Marc Wolf.]
Marc: And they stretch along the stem. Again, this is another plant people will argue with me about, too. It’s also called hobblebush because it layers itself, and if you’re bush-whacking in the forest up here, you come across hobblebush, you have to get around it because it really does trip you up.
But then the leaves are really large, almost like little saucers and really thick and almost like a blue green they’re so textural. And now, the fall colors are just crazy. Like it’s got every color, like a Spirographic 70s T-shirt kind of thing. It’s just all over the place.
Margaret: Well, generally speaking, the viburnums have not only the spring flowers, and then fruit in late summer or fall, but also good fall color. I mean, acerifolium, the maple-leaf Viburnum, that’s really shade-tolerant. And that’s a great understory plant.
Marc: Both of those, I would say aren’t really hedge plants because they’re a little scrappier.
Marc: They’re great woodland edge… Like edge of the woodland, but not hedge necessarily.
Margaret: Like what I was talking about in the beginning, what I’m trying to do is create more edge around, under the canopy trees and so forth. And there’s so many different ones.
Marc: Viburnum cassinoides.
Margaret: Yeah, cassinoides. Right.
Marc: Which is sort of a Northern relative of nudum. Really, really similar. Hardier. I think it deals better with a heavy snowload in terms of branches breaking, I think, but amazing fall color. The berries of nudum and cassinoides, the way they go from like light pink to dark pink to blue with purple. [Above, the fall foliage of V. cassinoides with a colorful caterpillar; photo by Marc Wolf.]
Marc: They’re crazy, too.
Margaret: Yeah. And some prunifolium, the fruit starts out sort of yellowish and turns black, the blackhaw viburnum. And you do get the viburnum leaf beetle up there?
Marc: Oh, yeah, we do get it. And we do grow dentatum, which is really hammered by the leaf beetle. We also grow opulus var. americanum, the highbush cranberry, which is not a cranberry it’s a viburnum. And what we do is we scout for the egg cases in the early spring. Although I think you probably could start scouting in late fall and we cut those off.
Margaret: Yeah. Around November, you could. Yes.
Marc: O.K. So we usually do it like February, March, and it’s really, you have to train your eye, but once you train your eye, you can do this and you cut back… You’re going to cut back flower, too, but I think you can beat back the population. Then we all also spray with like a horticultural oil just before they leaf out. So they take a lot of work, that’s dentatum and the highbush cranberry.
I don’t know what your experience is with acerifolium—doesn’t really seem to bother it too much. And then the others that we are planting knock on wood, they seem O.K.
Margaret: Yeah. And what I do is I have the cranberrybush one, and I use it as almost like a trap crop. And I know I’m going to get all my egg cases over there and all my damage over there. I have it out of the way, a couple of plants. Like a farmer would put a trap crop-
Marc: Yeah. That’s a great idea.
Margaret: … away from his field. And that’s where I go and cut off the egg cases in November, December, January, February, March.
So if people have a moist spot. Is buttonbush something that we could be growing?
Marc: Yeah, totally. I mean, and in standing water. Moist or standing water.
Margaret: So tell me the name of it and…
Marc: Cephalanthus occidentalis. [In flower, above, by Marc Wolf.]
Margaret: Yeah, Cephalanthus. Right.
Marc: The thing about buttonbush, is it leafs out late. So we luckily realized that, and at the arboretum we planted at the far end of the rain garden. So you don’t really know that it looks dead [laughter]. And then when it does leaf out after everything else, it’s got this chartreuse, light green, gorgeous leaf. So it really stands out from far away, but then you have to get close to it because those like little sputnik flowers, like 1-inch like pincushion but round, circular flowers that persists through the winter. They’re great. It’s a great shrub, beautiful form, beautiful shape and really takes wet sun.
Margaret: So many possibilities, Marc Wolf from Mountain Top Arboretum. Of course, the time all goes too fast and we’re going to have 10 more conversations [laughter]. I’m glad to talk to you again today. And now of course, I have more plants on my list that I have to go find for my project. So thanks a lot, Marc.
Marc: [Laughter.] Me too. Thank you, Margaret.
enter to win the book ‘twenty-one trees’
I’LL BUY A COPY OF “Twenty-One Trees” from Mountain To Arboretum, photographed by Rob Cardillo, for one lucky reader. All you have to do to enter is answer this question in the comments box farther down the page:
Is there a favorite garden-sized native woody plant in your yard that you are particularly fond of?
No answer, or feeling shy? Just say “count me in” or something to that effect, and I will, but a reply is even better. I’ll pick a winner after entries close at midnight Tuesday October 12, 2021. Good luck to all.
prefer the podcast version of the show?
MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its 11th year in March 2020. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the Oct. 4, 2021 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify or Stitcher (and browse my archive of podcasts here).