Category Archives: Trees

Fall Fruitfulness at the Arnold Arboretum

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At 281 acres (113 hectares), Boston’s Arnold Arboretum is not the kind of place you waltz through in a few hours.  (And this is not the kind of blog you waltz through quickly – unless you’re a plant geek like me. Fair warning.)

So when we arrived on Sunday, October 8th after driving from New Hampshire, braving Boston’s famous traffic and entering the garden via the Walter Street gate and Peters Hill, we knew we wouldn’t be seeing much of it that day.  Fortunately, we would return on Monday morning and enter from the main Arborway Gate – and I’ve put both entrances on the garden map below.

Unlike the rest of the arboretum, Peters Hill – which is a “drumlin” in geological terms, a hill comprised of glacial till deposited as the glaciers retreated around 12,000 years ago and the third highest hill in Boston – also features a meadow, which in October was mostly native asters and non-native Queen Anne’s lace. 

But I was aiming at Peters Hill because it has the arboretum’s collection of crabapples, hawthorns and mountain ash trees, among other species – and I knew they would be in fruit now.  It was an opportunity to find one of my favourite crabapples, Sargent’s crabapple, or Malus sargentii, a beautiful, dwarf species covered in May with white blossoms and buzzing bees. It was named by the Arnold’s resident taxonomist and dendrologist, German-born Alfred Rehder (1863-1949), in honour of…..

….the Arnold Arboretum’s first director Charles Sprague Sargent (1841-1927), who collected seed of the small tree in a salt marsh in Japan in 1892. He also collected seed of a cherry on that trip which, though other botanists had previously classified it as different species, would also be named for him, Prunus sargentii, Japanese hill cherry or Sargent’s cherry.  Charles Sargent had graduated from Harvard College in Biology in 1862, served with the Union Army during the Civil War, then returned to his wealthy family’s 130-acre Brookline estate to manage its landscape. When Harvard decided to establish an arboretum in 1872, he was appointed its director, a position he held for 55 years until his death. The photo below was made in 1901 when he was 60. In reading the memorial written by Arnold taxonomist Alfred Rehder in 1927, one gains a sense of the immense size of Charles Sargent’s accomplishments, at the Arnold, in the native sylva of North America, and throughout the world in the plants he himself collected and those collected under his supervision.

Perhaps the Arnold’s most renowned personality is Ernest Henry “Chinese” Wilson (1876-1930). Born in Chipping Camden, Gloucestershire, he was travelling to San Francisco from New York by train in spring 1899 on his first Chinese plant collecting trip for James Veitch & Sons nursery in England when he visited the Arnold Arboretum for five days with a letter of introduction to Charles Sargent, in order to learn their techniques for preserving shipped plants and seeds.  On his second trip for Veitch’s in 1903, he collected the regal lily (L. regale). But he had so impressed Charles Sargent that he was offered a job in 1906 doing plant exploration for the Arnold, with journeys to China made in 1907, 1908 and 1910; one to Japan in 1911-16 for cultivated cherries and azaleas; Korea and Formosa in 1917-18; and New Zealand, India, Central and South America in 1922-24 to establish connections with botanical gardens and explore southern gymnosperms.  He was Assistant Director of the Arnold from 1919-27, and following Charles Sargent’s death in 1927, Wilson assumed the role of Keeper of the Arboretum.  A skilled story-teller, he also wrote hundreds of articles and several books.  He died in 1930 at the age of 54 along with his wife in a tragic car accident in Massachusetts while returning from a visit to their daughter in upstate New York.  

Below are just a dozen of the 2,000 species Wilson is credited with introducing to the western world.  Others include Stewartia sinensis and Malus hupehensis.

1-Acer griseum, 2-Actinidia deliciosa-kiwi, 3-Clematis armandii, 4-Cornus kousa var. chinensis, 5-Ilex pernyi, 6-Jasminum mesnyi, 7-Kolkwitzia amabilis, 8-Lilium regale, 9-Rhododendron davidsonianum, 10-Rhododendron decorum, 11-Rhododendron williamsianum, 12-Rosa moyesii

I wanted to have a look at the fruit of the crabapple species on Peters Hill, although summer’s abundant rain had resulted in considerable apple blight on the leaves.  Below is Malus ‘Golden Hornet’….

….. and Malus ‘David’….

…. and the tiny yellow fruit of Malus x robusta var. xanthocarpa (Malus baccata x M. prunifolia).

Charles Sargent was especially interested in hawthorns, and the hawthorn collection also resides on Peters Hill, including cockspur thorn (Crataegus crus-galli) with its vicious thorns.

Sorbus commixta is sometimes called the Japanese rowan; its orange fruit is as attractive as its spring flowers.

One of my favourite small Sorbus species is Korean mountain ash, S. alnifolia.  It was covered with tiny, salmon-pink fruit.

Tired from our long driving day and walk, we sat on a bench on Peters Hill. I loved that the Arnold turns fallen trees into these handsome benches – this one was a red oak (Quercus rubra) that blew down in a windstorm on October 30, 2017 that left 1.5 million people without power.

As we circled Peters Hill to head out and drive to our hotel in nearby Dedham, we came upon a hive of activity marking the Arnold’s “Second Sunday” event, one of three offered in late summer/early autumn 2023. According to the website, these days “reflect an institutional value to expand our welcome and outreach to all surrounding neighborhoods, especially those that have received less attention in the past. The events offer visitors opportunities to learn more about Peters Hill as well as venture into other areas of our landscape that lie off the beaten path”.  Arnold intern Zach Shein, below, was manning one of the booths and showing off some of the arboretum’s “spooky plants” in time for Halloween. 

Here were a few of his samples, clockwise from upper left:  poison ivy (Rhus radicans);  trifoliate orange (Citrus trifoliata); castor bean (Ricinus communis); and autumn monkshood (Aconitum carmichaelii Arendsii Group).  

Nearby, Arnold evolutionary biologist Anna Feller was explaining her research on the reproductive strategies of Phlox paniculata to interested visitors.  Then it was time to find our hotel for the night in nearby Dedbury.

*****

The next morning, refreshed, we returned to the Arnold’s main gate for a longer visit.  Since it was Indigenous Peoples Day, the Hunnewell Visitor Center (1892) was closed.  But we wanted to be outside anyway here at North America’s first public arboretum.  A National Historic Landmark, the Arnold Arboretum is owned by the City of Boston and managed by Harvard University under a 1,000-year lease signed in 1882. It is a major part of the Emerald Necklace, a 7-mile network of parks and green spaces laid out by landscape architect Frederick Law Olmsted for the Boston Parks Department between 1878 and 1896.  As a city park, it is free to all.  

In an arboretum, one expects to find native plants like tuliptree, but I was interested in the tree below, Liriodendron x sinoamericanum, a hybrid of the American and Chinese species.

I stood under the pagoda or giant dogwood (Cornus controversa) from Asia to admire the beautiful symmetry of its foliage. This species and my favourite native shrub, Cornus alternifolia (I grow five in my garden), are the only dogwoods with alternate leaves.

Black tupelo (Nyssa sylvatica) is one of the last deciduous trees to turn colour, usually bright gold-to-red, before losing its leaves.  

I’ve photographed a lot of lindens, but this was my first Amur linden (Tilia amurensis).

Trifoliate orange (Citrus trifoliata) is a hardy member of the citrus family, Rutaceae.  Although very seedy, the fruits are edible, but bitter (good for marmalade, I hear) – and the wicked thorns are an effective deterrent to herbivory.

We came to the Leventritt Shrub & Vine Garden and spent time strolling through this 3-acre collection.

Flowering dogwood (Cornus florida) leaves were changing colour and the fruit had already been sampled by birds.

I liked the deep-wine fall colour of this smooth arrowwood viburnum (Viburnum recognitum), a native northeast shrub previously unknown to me. But the great surprise came when I looked at the plant label, for it had been sourced in 1968 from the Dominion Arboretum in Ottawa, specifically from L.C. Sherk.  Larry became a friend of mine decades later when he was chief horticulturist for an Ontario nursery chain.

The goldenrain tree (Koelreuteria paniculata) gets its common name for its yellow flowers, but in late summer it develops interesting capsule fruit, below, which are rose-colored before turning brown.  This tree is ‘Rose Lantern’.

I had never seen Isodon henryi before, but was interested to read that its unique properties makes it a “frost flower” on certain wintry days.

Walking under the vines arrayed neatly on the rows of steel trellises in the garden, I looked up to see the backlit leaves and prickly stems of Smilax sieboldii from Asia, and thought how apropos is the common name of members of this genus:  greenbriar”. 

Next up was the Arnold’s Bonsai & Penjing exhibit.  It is amazing to think that this Hinoki cypress (Chamaecyparis obtusa ‘Chabo-Hiba’), acquired in 1937 by the Arnold as part of former American Ambassador to Japan Larz Anderson’s Collection of Japanese Dwarfed Trees, actually germinated in 1799. 

Smooth cranberry bush viburnum (V. opulus var. calvescens), a European species, bore clusters of red fruit very similar to native N. American highbush cranberry.

…. while the large Asian shrub sapphire-berry (Symplocos paniculata) was attracting lots of admirers with its brilliant blue fruit.

Not to be outdone, Japanese beautyberry (Callicarpa japonica ‘Leucocarpa’) bore its white autumn fruit like a pearl cluster necklace.

Sometimes, as a plant photographer, I forget to see the forest for the trees, so I took a moment here to gaze across the Bussey Hill landscape with its remarkable collection of towering trees and fruiting shrubs. Throughout the arboretum, visitors were enjoying the warm fall weather and I saw many families engaging their kids in the natural world. What a gift is the Arnold Arboretum to the people of Boston.

Then we headed up to the Explorers Garden….

…. and took  the Chinese path to climb the hill. (This signage reminded me of the wonderful David Lam Asian Garden at the University of British Columbia Botanical Garden, where various path signs are named after explorers like von Siebold, Fortune, Forrest, Henry, Kingdon Ward and yes, the Wilson Glade. This is my blog on that fabulous garden.)

In the Explorers Garden we found the two oldest Franklin trees (Franklinia alatamaha) in the world, still bearing a few beautiful, perfumed, white blossoms, below. Naturalist William Bartram (1729-1823) named this tree, which he grew from seed he collected in 1776 from a small, relict population growing along the banks of the Altamaha River in coastal Georgia. He named it to honor Benjamin Franklin, a good friend of his father, the American botanist and early plant explorer John Bartram (1699-1777), with whom William had first seen the tree 11 years earlier. (Franklin, of course, helped draft the Declaration of Independence and the American Constitution and is featured on the American $100 bill.)  The specific epithet refers to an alternative historic name of the river. There are no longer Franklin trees growing in the wild; it is believed that the trees the Bartrams found were glacial survivors on their way to extinction.

The interpretive sign includes information on the species.  A relative of Stewartia and Camellia, the Franklin tree is a member of the tea family, Theaceae.  In temperate regions, it blooms in September and October, unusually late for a woody plant, and displays its fragrant flowers alongside showy autumn foliage. The two Franklin trees growing in the Arnold Arboretum’s garden are the oldest and largest such trees in the world. They came from 1905 cuttings of a tree grown in Bartram’s Philadelphia garden that had sent to the Arnold in 1884.

They sprawl like giant shrubs, rooting themselves wherever their branches make contact with the ground. Now widely available in commerce, Franklin tree is difficult to establish, preferring sandy, acidic soil that remains consistently moist.  Today, the species itself is kept alive through cultivation in gardens.

Moving on, we came to Chinese fringetree (Chionanthus retusus) with handsome blue fruit.

Seven-son-flower (Heptacodium miconioides), so named for the seven small, white flowers in each cluster, was now showing off its bright red calyces or sepals.  This autumn show and the bee-friendly September flowers are highlights of this large, sprawling shrub. According to Gary Koller, writing for the Arnold, Henry ‘Chinese’ Wilson “collected the plant at Hsing-shan in western Hupeh (Hubei) province, China (Collection Number 2232). He made two collections of it, one in July and the other in October 1907, from cliffs at nine hundred meters (about three thousand feet) above sea level, where it was rare. In examining the herbarium specimens, Rehder (the Arnold’s taxonomist) found ‘that only a single ripe fruit was available for examination,’ which probably explains why no living plants resulted from that expedition. Rehder named the plant Heptacodium miconioides.”  It would not be until the 1980 Sino-American Botanical Expedition, in which the Arnold’s Steven Spongberg participated, when seed obtained from a shrub growing in the Hangzhou Botanical Garden was brought back to the U.S. that seven-son-flower would be grown in North America.

Another species growing in the Explorers Garden from seed collected by the Sino-American Botanical Expedition is a mountain-ash-like tree called Yu’s whitebeam, Alniaria yuana (formerly Sorbus), with plump, shiny fruit.

As we headed back towards our car, we passed the Euonymus collection, all in fruit, including the pink capsules of flat-stalked spindle (E. planipes), with the orange fruit still to be revealed.  It was labelled E. sachalinense, but I believe that name has been changed, according to sources online.

I was also pleased to see the fruiting habit of a plant I know from the collection at my local Mount Pleasant Cemetery, Oriental photinia (P. villosa var. villosa).   I even included it in a blog called June Whites. But you can see that the leaves on this species, as well as most of the Malus, Crataegus and other members of the Rosaceae family, were afflicted with disease, likely fire blight, after a very wet spring/summer in 2023.

I heard the clip-clop of a horse and looking at the road was greeted with the smile of a passing Boston Park Ranger. Mounted rangers patrol the arboretum and other parks in the Green Necklace.

We took a different road towards the exit than the one on which we’d entered three-and-a-half hours earlier; that brought us close to one of the Arnold’s three ponds. Originally maintained as decorative features, recent restoration has resulted in a naturalistic habitat for aquatic wildlife and plants, including the bald cypress at left. It felt like the perfect ecological bookend to the historic Hunnewell Building where we’d begun our visit, on this fine October day.

*****

If you’re planning a garden trip to New England, I highly recommend Jana Milbocker’s excellent ‘The Garden Tourist’s New England‘, featuring 140 private and public gardens and nurseries. It’s available on her website Enchanted Gardens.

Fairy Crown #26-Fall Finery

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For me, autumn is a time of richness as the gardening season nears its end in an explosion of pigments and seedheads.  Those pigments, in particular, have always fascinated me and I made a concerted effort to use brilliant fall foliage colours in my own garden design.  So today’s fairy crown, the 26th, features the fall leaves and fruit of shrubs and trees in my Toronto garden in early November, including Japanese maple (Acer palmatum), Washington thorn (Crataegus phaenopyrum), burning bush (Euonymus alatus ‘Compactus’), barberry (Berberis thunbergii ‘Rose Glow’) and, draped down my front, a compound leaf of my black walnut (Juglans nigra).

Every year is a little different in terms of the parade of colour. Here you see my Japanese maple showing off its regular autumn leaf change as the burning bush hedge turns colour. In the pollinator garden, the ‘Autumn Joy’ sedum seedheads are ruby-red, but the fothergilla haven’t begun to change yet. The columnar red maple (upper left) that the city chose for my boulevard (I asked for one that turns red) has taken on its disappointing dishwater-yellow. Red maples, of course, don’t always turn red in fall.

In this photo taken a different year, the fothergilla in the pollinator garden is a rosy-apricot.  That’s catmint in the front giving a nice glaucous contrast with Russian sage and echinacea seedheads adding structure.

From across the street, my neighbours see my garden through the fan-shaped yellow leaves of my second boulevard tree, a ginkgo (G. biloba).  

If you’ve followed my blog for a while, you likely know that I’ve had fun turning those yellow leaves….

….. into ballet tutus of tiny dancers.

The Japanese maple (Acer palmatum) I planted in front of my living room window decades ago is a great joy to me. It’s the straight species with green leaves – in Japan it would be a common forest tree.  But in my garden, since there are no drapes on my front window, it forms a lacy curtain from spring (when bees buzz around the tiny May flowers) to fall. In very late October or the first week of November, the foliage turns a range of rich hues from yellow to apricot, scarlet and crimson.

The leaves are delicate, their branching exquisite. It’s no wonder they were the subject of the renowned Japanese woodblock artists like Hiroshige and Kuniyoshi.

As I’ve written before, my Japanese maple’s brilliant autumn colour lights up my living room in early November….

….. enhancing the glass witches’ balls I’ve suspended from the window frame.

And, of course, the leaves also provided me with an appropriate costume and landscape for my little geisha.  

If there’s a saying that “good fences, good neighbours make”, it can also apply to hedges – which was how I ended up making this hedge in my front garden more than 30 years ago. (My current neighbours are lovely!) Today, environmentalists tend to shun burning bush, given its invasive tendency in milder regions, but my hedge produces very few seedlings, unlike the Norway maples in my neighbourhood which are a scourge. And this neon display in autumn is truly amazing.

My belly dancer’s costume was made from the leaves of my burning bush hedge.

Though there’s no fothergilla in my crown, it is definitely a big part of the fall colour in my front garden.  In this photo made just before Halloween, you can see one of my shrubs has turned a rich burgundy-red beneath the Japanese maple.

The richer, more moisture-retentive soil in my pollinator island tends to produce orange and gold colours in the three fothergilla shrubs there.

Look at those colours! Who needs the spring flowers….

…. though they are lovely, if short-lived, in late May.

And, yes, I did harvest my flamenco dancer’s multi-colored skirt from my fothergillas.

Turning colour a little later in the front garden is my paperbark maple (Acer griseum) with its red trifoliate leaves.

Moving into the back garden, you see Boston ivy (Parthenocissus tricuspidata) cloaking the driveway gate.  I didn’t plant this vine, nor did I plant all the Virginia creeper vines that pop up throughout the garden. That’s Mother Nature’s role and she’s very enthusiastic about it (!)

I confess that I wanted the Washington thorn tree (Crataegus phaenopyrum) in my garden long ago purely for its multi-hued fall leaves.

But it turned out to be a wonderful tree for bird life – IF the birds can out-compete the squirrels for the fruit. The robin, below, managed to do that, but so have cedar waxwings and cardinals.

Here you can see the range of autumn colour in the foliage of Washington thorn.

When we bought our house in 1983, the native black walnut tree (Juglans nigra) on the property line between us and our next-door neighbour was already mature. In the 39 years since then, it has hosted raccoon families in the crook of its trunk, carpenter ants in its bark and countless cardinals practising their song in its branches.

Our bedroom sits right under the tree, but we seemed to have missed the obvious ramifications of putting a skylight in our ceiling – particularly when windy nights in September roll around and the roof is pummelled with billiard-ball-sized nuts. Though the skylight has proven strong, we’ve replaced two car windshields since the tree’s branches — and nuts — extend far over the driveway.

The walnuts are enjoyed by the neighbourhood squirrels….

….. but the natural dye in the husks creates an unbelievable mess.

The arborist has told us the tree has rot in the trunk, but my neighbour and I have had it cabled and pruned away some of the branches over our houses to reduce the nut fusillade. It is our tree, after all, it gives us shade and we feel a duty to keep it – thus its inclusion in my 26th crown. 

I don’t really notice the ‘Rose Glow’ barberry (Berberis thunbergii) in my back garden until it turns rich crimson-red in autumn – then it’s a show-stopper. It’s another one of those shrubs that environmentalists shun – especially in milder U.S. regions where it seeds around freely. I haven’t seen one seedling in my Toronto garden.

I have a fairly new addition to my back garden:  a little sassafras tree (S. albidum). which I wanted especially for its fall colour.  This autumn – admittedly one of the best for colour in many years – it has begun to display the reds, corals and yellows for which it is known.

Those colours, by the way, are on leaves that exhibit three distinct shapes:  elliptical; mitten-like and three-lobed.  This is what they look like on my light table.

Designing with and celebrating fall-colored plants and shrubs is my way of expressing my appreciation for nature’s yearly preparation for winter, as it cycles through the yellow/orange “accessory” carotene pigments in the leaves of certain species to harvest and synthesize as much sunshine as possible, once the ‘green’ pigment chlorophyll breaks down in cooler temperatures. Red colour is from anthocynanis. According to the USDA, “Anthocyanins absorb blue, blue-green, and green light. Therefore, the light reflected by leaves containing anthocyanins appears red. Unlike chlorophyll and carotene, anthocyanins are not attached to cell membranes, but are dissolved in the cell sap. The color produced by these pigments is sensitive to the pH of the cell sap. If the sap is quite acidic, the pigments impart a bright red color; if the sap is less acidic, its color is more purple. Anthocyanin pigments are responsible for the red skin of ripe apples and the purple of ripe grapes. A reaction between sugars and certain proteins in cell sap forms anthocyanins. This reaction does not occur until the sugar concentration in the sap is quite high.”   Because the reaction requires light, you often see leaves (or apples) fully exposed to sun that are red while those parts that are shaded stay green or yellow, like these Boston ivy leaves on my fence.

I love making the leaf montages that celebrate these pigment changes, like the one below from leaves in my garden.

A few years ago I even held a photography show called “Autumn Harvest” featuring a number of my leaf montages.

Finally, this week as I walked out onto my front porch and gazed into my garden, this is what I saw– a multi-hued tapestry that shows that nature is the best designer of all. It’s my reward for a gardening season that began seven months ago with the first snowdrops and will soon come to an end with the first hard frost.

******

My year of fairy crowns is soon drawing to its wintry finale. If you missed a few, here they are:

#1 – Spring Awakening
#2 – Little Blossoms for Easter
#3 – The Perfume of Hyacinths 
#4 – Spring Bulb Extravaganza
#5 – A Crabapple Requiem
#6 – Shady Lady
#7 – Columbines & Wild Strawberries on Lake Muskoka
#8 – Lilac, Dogwood & Alliums
#9 – Borrowed Scenery & an Azalea for Mom
#10 – June Blues on Lake Muskoka
#11 – Sage & Catmint for the Bees
#12 – Penstemons & Coreopsis in Muskoka
#13 – Ditch Lilies & Serviceberries
#14 – Golden Yarrow & Orange Milkweed
#15 – Echinacea & Clematis
#16 – A Czech-German-All American Blackeyed Susan
#17- Beebalm & Yellow Daisies at the Lake
#18- Russian Sage & Blazing Stars
#19-My Fruitful Life
#20-Cup Plant, Joe Pye & Ironweed
#21-Helianthus & Hummingbirds
#22-Grasses, Asters & Goldenrod
#23-Sedums, Pass-Along Plants & Fruit for the Birds
#24-Fall Asters & Showy Goldenrod for Thanksgiving
#25-Autumn Monkshood & Snakeroot

Marvelous Magnolias

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As part of my series on spring trees and shrubs, I thought it might be fun to take a deep dive into some of the many magnolias I’ve encountered during my garden travels over the past three-plus decades. As I said to someone, “I spend a lot of time writing about useful sparrows. Every now and then, I like to focus on the peacocks.”  And magnolias, like peacocks, were precious cargo for the earliest botanical explorers collecting seeds and cuttings from far-flung shores.

By the time Carl Linnaeus published Species Plantarum in 1753, thereby assigning binomials (two-word Latin names) to the known plants of the world, Pierre Magnol, the highly respected director of the botanical garden at Montpellier in southern France had been dead for thirty eight years. But Magnol had been honoured in 1703 by botanist Charles Plumier in the naming of a West Indies magnolia, M. dodecapetala. 

It was a time of discovery in the New World, as plant explorers visited the American colonies, sending back seeds and plants in Wardian cases. One of those explorers, Mark Catesby, travelled through Virginia and Carolina from 1722 to 1726, tramping through swampy woods and finding a magnificent tree with large, waxy, lemon-scented, white flowers which he called the Laurel Leaved Tulip Tree or Carolina Laurel. He made a preparatory drawing of the tree which came back with him to England in a trunk, along with drawings of many other plants and a few seeds and herbarium specimens. His drawings were the first Europeans had seen of plants and birds of North America. Some were repainted by other artists, then engraved as plates and published in ten parts from 1729-1748 in a collection called Natural History of Carolina, Florida and the Bahama Islands.  Thus was Catesby’s Laurel Tree of Carolina, Magnolia altissima, flore ingenti candido, later named simply Magnolia grandiflora by Linnaeus – memorialized in 1744 in the hand-coloured etching, below, by Georg Dionysius Ehret.

Today we know this beautiful species as southern magnolia. I found it in bloom in the Beatrix Farrand-designed landscape at Dumbarton Oaks in Washington, D.C., now owned by Harvard University. I wrote a blog about my June 2017 visit to this spectacular garden.

Southern magnolia has made its way around the world, including an old specimen in the garden at Akaunui Farm Homestead in New Zealand, which I blogged about in 2018.  The tree grows 60-80 ft tall (18-24 m) and 30-40 ft (9-12 m) wide, though some in Mississippi have reached 120 ft (36 m) in height.

And it was on fragrant southern magnolia flowers near the beach in New Zealand where I found honey bees feverishly gathering pollen from the stamens.

Magnolias feature a cone-like aggregate fruit called a “follicetum”, like the one below from M. grandiflora.  

Magnolia ancestors are among the most primitive plants, having evolved in the Cretaceous (145-66 million years ago) with the dinosaurs, and they ranged in places far from where we find them today.  Wrote John Fisher in The Origins of Garden Plants, “the climate in the northern hemisphere remained mild, and magnolias, bread fruit and camphor trees flourished on the west coast of Greenland – 300 miles north of the Arctic Circle.” This is a photo by Geology Professor James St. John shared under Creative Commons Attribution of a fossil leaf of extinct Magnolia boulayana, from the Cretaceous flora of Alabama, USA from the Field Museum of Natural History, Chicago, IL.

Fossil leaf of Magnolia boulayana from the Cretaceous of Alabama – Field Museum, Chicago. Shared from Professor James St. John under Creative Commons

Though we cannot grow southern magnolia in Toronto, we can enjoy its leathery, bronze-backed leaves in winter arrangements like the ones below, on my back deck.

But Magnolia grandiflora was not the first American magnolia species to cross the Atlantic. The Bishop of London and head of the Anglican church in the American colonies, Henry Compton, had a garden at Fulham Palace and was an avid collector of rarities. He sent the missionary John Banister to Virginia in 1678; in the coming years, he would prepare a catalogue that represented the first survey of native American plants. One of his discoveries was the sweetbay,  Magnolia virginiana, with creamy scented flowers. It was used medicinally by the native Indian tribes of the southeast, who prepared decoctions to treat rheumatism, fever and consumption.  It would become the first of the genus to be successfully grown in Britain. I found M. virginiana ‘Green Shadow’ below, growing on New York’s High Line.   

I also found another native American magnolia on the High Line: M. macrophylla var. ashei, Ashe’s magnolia, below. Closely related to the taller bigleaf magnolia (M. macrophylla), it was named for William Willard Ashe (1872-1932) of the U.S. Forest Service. Though we often think of Dutch designer Piet Oudolf as a creator of four-season meadows, he is also skilled at using regionally native shrubs and trees for specific applications in his designs.

Beetles are considered to be the evolutionary pollinators of magnolias, since the plants evolved in the Cretaceous before bees appeared. But bees certainly take advantage of the flowers, as we see below with a native megachile leafcutter bee foraging on Ashe’s magnolia.

The only magnolia native to Canada – or at least the Carolinian Forest in extreme southern Ontario where it is listed as ‘endangered’ – is cucumber tree (Magnolia acuminata var. acuminata).  Though it does not grow in the wild near me in Toronto, it is nonetheless hardy here and there is a lovely specimen in the 200-acre Mount Pleasant Cemetery, below. It is much smaller than its southern counterparts which can reach 80 ft (25 m).  Cucumber magnolia is morphologically variable, and the southern form, M. acuminata var. sub cordata, has been used in breeding with Asian magnolias to produce many of the highly prized yellow cultivars below.

The flowers of cucumber magnolia are unusual looking with green outer tepals cupped around yellow inner tepals. They close at night.

The tree gets its common name from the cucumber-like appearance of the unripe fruit, which turns red in late summer. 

Enter the Asian Magnolias

The first popular magnolia resulting from a 1956 cross of cucumber magnolia with the white-flowered Chinese Yulan magnolia (M. denudata) was called ‘Elizabeth’. Created by Dr. Evamaria Sberber at the Brooklyn Botanical Garden…..

…. its soft-yellow, precocious flowers (i.e.appearing before the leaves) marked a new chapter for magnolias.

But breeders wanted even brighter, longer-lasting yellows. This is the beautiful ‘Butterflies’, a 1990  cross of  M, acuminata ‘Fertile Myrtle’ x M. denudata ‘Sawada’s Cream’ by famed Michigan magnolia breeder Phil Savage.

My photos of  ‘Butterflies’, below, illustrate the reproductive strategy of magnolias. The flowers are protogynous, meaning the flowers open initially in the female phase during which the curved stigmas are receptive (top). They then close, only to reopen with the male reproductive organs, the pink-tipped stamens, ready to shed pollen (bottom). Magnolias evolved this system to improve the chance of cross-pollination, rather than self-pollination, thus strengthening the genetic diversity.

I have blogged previously about the wonderful yellow magnolias in the collection of the Montreal Botanical Garden – see “Mellow Yellow Magnolias” – so I won’t repeat myself here, other than to offer this montage of a selection of those beauties.


1- ‘Golden Sun’, 2 -‘Maxine Merrill’, 3-‘Banana Split’, 4-‘Yellow Bird’, 5-‘Golden Goblet’, 6-‘Sunburst’, 7-‘Limelight’, 8-‘Golden Endeavour’, 9 -‘Tranquility’

There are a number of hardy Asian magnolias for our climate (USDA Zone 5–Can. Zone 6), though their early flowering sometimes coincides with a spring frost. Native to Japan and Korea, the Kobushi magnolia, Magnolia kobus var. kobus, is a small tree or large shrub that grows 25-50 ft tall (8-15 m) with a wide spread. I have photographed specimens in Toronto’s Mount Pleasant Cemetery and at the Royal Botanical Garden in Burlington, ON, below.

The white flowers of M. kobus are considered by some to be the most fragrant of the early magnolias. According to Helen Van Pelt Wilson and Léonie Bell in their book The Fragrant Year, the blooms distill “the ripe mango aroma of orange and pineapple softened by a note of lily, a perfume noticeable many yards away. Later the glossy leaves and gray twigs, crushed, have the spiciness of bayberry.”

The lovely star magnolia from Japan, Magnolia stellata, is related to M. kobus (some botanists consider it a variety) and a good choice as a tree or shrub for a small garden, given it usually doesn’t grow taller than 10 feet (3 m) with a spread of 15 feet (4.6 m). It bears at least 12 ribbon-like tepals, usually white but with natural variants such as var. rosea and var. rubra of pale rose to pink. When I was a young girl in the suburbs outside Vancouver, BC, my mother grew a star magnolia outside my bedroom window. It had a light perfume, one that Wilson and Bell describe as “watermelon or honeydew blended with Easter lily.”  

I photographed one of the more bizarre design uses for star magnolia one spring at Ontario’s Royal Botanical Garden in their “hedge plants” area. 

Ask most gardeners in the northeast what their favourite magnolia is and they’ll likely describe the ‘tulip tree’ or the ‘saucer magnolia’, both names for the widely available, hardy hybrid Magnolia x soulangeana.  Now almost two centuries old, it is reported to have appeared in 1826  in the garden of M. Soulange-Boudin at Fromont near Paris, an accidental cross between two Chinese species, the pure white Yulan,  M. denudata and the mulberry coloured Mulan, M. liliiflora.  On a well-grown shrub, those upturned rose-pink goblets are utterly enchanting in early spring, just when winter-weary gardeners are starved for beauty.

There are beautiful, mature specimens in Toronto’s Mount Pleasant Cemetery, usually flowering in mid-late April, the same time as the early Japanese cherries and native plums, depending on the season. The oldest specimens reach 15-20ft (4.6-6 m) with a large spread.  

I believe this is the cultivar M. x soulangeana ‘Lennei Alba’, introduced in 1931 by Terra Nova Nurseries in Holland.

Saucer magnolias can be found throughout the temperate world. I photographed ‘Verbanica’, below, an 1873 introduction from France at Van Dusen Botanical Garden on May 2, 2017. Note that its later flowering has also meant that the flowers are not ‘precocious’, i.e. the leaves have also emerged.

In warm climates, M. x soulangeana often flowers in winter. I photographed ‘Lilliputian’, below, bred  for its miniature form and flower size, at the Los Angeles County Arboretum on January 6, 2018.

Now for my personal favourites, the Loebner hybrids, so-named because they were first created in the early 1900s from crosses between the Japanese species Magnolia kobus and M. stellata by renowned German horticulturist Max Löbner (1869-1947).  The one I admire each spring at the Toronto Botanical Garden, below, is the white-flowered cultivar ‘Merrill’. It was grown from open-pollinated seed in 1939 by a student of research scientist and professor of genetics Karl Sax at Harvard’s Arnold Arboretum. Sax named the cultivar in 1952 for the retiring Arboretum director Elmer Merrill, whom Sax would replace as director.

Unlike its slow-growing star magnolia parent, ‘Merrill’ grows quickly to a mature height of 20-30 ft (6-9 m), i.e. less than M. kobus.  The large, slightly fragrant flowers that appear on the bare branches are white flushed with pink, the tepals slightly broader than those of star magnolia. It is truly lovely.   

My other favourite Loebner hybrid is pink-flowered ‘Leonard Messel’.  An award-winning 1955 cross between M. kobus and M. stellata var. rosea from Nymans Garden in Sussex, England, home of the Messel family, this cultivar has more of star magnolia’s dainty appearance, its pink, ribbon-like tepals fluttering in the breeze.  At the Toronto Botanical Garden, there are two shrubs, including this one in a sheltered corner on an inner terrace.

I have been known to spend long minutes focusing on the enchanting blooms……

….. that emerge like floral Cinderellas from the fuzzy brown winter buds.  

There are also a few ‘Leonard Messel’ magnolias at Mount Pleasant Cemetery, growing in relatively unprotected sites.

Now for the bad news:  f-r-e-e-z-i-n-g.  Unlike plants adapted to growing in sub-zero climates, Japanese magnolias hail from mountain regions where their flowering is timed with the onset of mild spring temperatures.  In Ontario, you can have an early spring in March that teases open magnolias, then snows on them, as it did with M. x soulangeana at Mount Pleasant Cemetery in April 2002…

….. or turns those March 2012 ‘Merrill’ flowers in my photo above to brown mush four days later. So a little caveat emptor is in order with magnolias.

The Oyama magnolia, Magnolia sieboldii, with its bright red stamens made its way quite dramatically from Japan to Europe with the German botanist and doctor, Philipp Franz von Siebold, physician to the Governor of the Dutch East India Company.  An eye surgeon who could remove cataracts, he had arrived in 1823 and therefore initially found popularity with government officials. He lived with his Japanese mistress with him he had a child and gardened with his newly found plants on the man-made port island of Dejima in Nagasaki prefecture. But when it was discovered that he had procured maps of the mainland, he was charged with espionage and imprisoned for a year. He was expelled in 1830 and was permitted to take his plants with him (including Hosta plantaginea, Corylopsis spicata, Clematis florida var. sieboldii, Fatsia japonica, Hamamelis japonica), but left his mistress and child behind. If this sounds like a fairytale, in fact Puccini’s 1904 opera ‘Madama Butterfly’ is based on von Siebold’s travails. As for Magnolia sieboldii, it is a beautiful small (10 ft – 3 m) woodland shrub for light shade and marginally hardy in Toronto where I have photographed it in June, but it thrives in milder parts of Canada.

The ‘Girl’ Series of hybrid magnolias were developed in 1955-56 at the U.S. National Arboretum by William F. Kosar and Dr. Francis de Vos.  They involved crosses of one of two of the Magnolia lilliflora  (the Mulan or woody orchid magnolia) cultivars ‘Nigra’ (below) and ‘Reflorescens’ and one of two Magnolia stellata cultivars ‘Rosea’ (var rosea) and ‘Waterlily’.

The resulting sterile hybrids, released in 1968, were named for the daughters of Kosar (‘Betty’) and de Vos (‘Ann’, ‘Judy’, ‘Randy’, ‘Ricki’); the daughter of Arboretum director Henry Skinner (‘Susan’); and the wife of U.S. Secretary of Agriculture Orville Freeman (‘Jane’).  Flowering 2-4 weeks later than M. stellata and M. x soulangeana, they are less at risk from late spring frost that will damage the flowers. Of the ones I’ve included below in this blog, ‘Ricki’ and ‘Ann’ are the shortest (10-12 ft or 3-3.6 m) with a 16-ft (4.8 m) width; ‘Jane’ is the tallest at 20-25 ft (6-7.6 m) with a 20-ft (6 m) width.  ‘Ann’, below, which I photographed at the U.S. National Arboretum is the earliest-flowering; ‘Jane’ is latest; the rest are midseason. 

 ‘Betty’ shows the upswept tepals of parent M. liliiflora.  It is a rounded, multi-stemmed shrub.

‘Susan’ sports twisted tepals; it is slightly fragrant.

The abundant tepals of ‘Ricki’ with their white interior hint at its M. stellata parentage.

Finally, here’s ‘Jane’ towards the end of her flowering period; unlike the others, her open blossoms recall the form of her parent M. stellata ‘Waterlily’.  

On an April 2008 trip to Ireland to find my grandfather’s ancestral home in the countryside near Banbridge (see my musical blog titled ‘Galway Bay’), we visted the National Botanic Garden, Glasnevin near Dublin where I found the magnificent Magnolia ‘Galaxy’ at on April 26, 2008. A late-flowering, tree-form magnolia with upward branching and a mature height of 30-40 ft (9-12 m), it is a 1963 cross between Magnolia liliiflora ‘Nigra’ and M. sprengeri ‘Diva’.  Like the ‘Girl’ Series, it was developed at the U.S. National Arboretum in Washington DC in 1963 and released in 1980.  

I love to visit Vancouver’s Van Dusen Botanical Gardens in spring; it’s where my mother and I would go to get our floral fix when I travelled ‘home’ from Toronto to visit her. There is so much to see there, I wrote a 2-part blog called ‘Spring at Van Dusen Botanical Garden’. One of the highlights is their magnolia collection, including Magnolia ‘Star Wars’, below, which I photographed on May 2, 2017. It was bred in New Zealand by Oswald Blumhardt, one of New Zealand’s renowned magnolia breeders. It’s a cross between Magnolia campbellii and M. liliiflora, bearing large, sweetly-scented flowers.

I photographed another New Zealand-bred magnolia at Van Dusen on May 2nd. This is ‘Apollo’, a Felix Jury cross between M. campbellii subsp. mollicomata ‘Lanarth’ and M. liliiflora ‘Nigra’. It is said to have a fruity fragrance but the flowers were too high for me to sniff.    

And finally, on Van Dusen’s Rhododendron Walk on that same May day, I found a stunning specimen of evergreen Magnolia cavalerei var. platypetala from China (formerly Michelia).  The fragrance was wonderful.

In 2019, I visited lovely Darts Hill Park Garden Park in South Surrey, outside Vancouver, B.C.  It is the home of the late plantswoman Francisca Darts (1916-2012) whom I was lucky to meet with my mom, Mary Healy, at the right below, one rainy spring day long ago.  I’m including this photo because my mother loved magnolias, she died the same year as Francisca, and she would be tickled pink to know that they are featured together under all these magnificent specimens.

During my 2019 visit to Darts Hill, I was interested to find Magnolia officinalis in flower, below.  Discovered originally in Sechuan, China in 1869 by French Abbé Henry David (of Davidia fame), it was found again as a cultivated plant in flower in 1900 by British plant explorer Ernest Henry Wilson who collected seeds that autumn to send to his then-employers at Veitch Nursery.  As he wrote later:  “The Chinese designate this species the Hou-p’o tree, and its bark and flower-buds constitute a valued drug which is exported in quantity from central and western China to all parts of the Empire. It is for its bark and flowerbuds that the tree is cultivated. The removal of’ the bark causes the death of the tree and this would account for its disappearance from the forests. The bark when boiled yields an extract which is taken internally as a cure for coughs, colds and as a tonic and stimulant during the convalescence. A similar extract obtained from the flower-buds, which are called Yu-p’o is esteemed as a medicine for women.”  Bark from the tree is used in Chinese medicine to this day.

I will finish this long wander through the hardy Magnolias with two recent arrivals, having been transferred there taxonomically from the former genus Michelia after genetic sequencing determined that Magnolioideae should contain only one genus. Included in that are 210 species of magnolias from around the world.  I found Magnolia laevifolia, formerly Michelia yunnanensis, at the San Francisco Botanical Garden (then Strybing Arboretum) one March long ago.

And though it was a little too bright at the Los Angeles County Arboretum on January 28, 2018 for good photos, I was delighted to find fragrant Magnolia doltsopa ‘Silver Cloud’ (formerly Michelia) in flower. 

As I gaze out the window in Toronto on this March day, winter is still holding on with a freshly-fallen blanket of heavy, wet snow. But spring is surely just around the corner – and with it, those spectacular floral peacocks, the magnolias.

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Anxious for spring, too? See my recent blogs on tuliptree (Liriodendron tulipifera),  redbuds (Cercis canadensis and its cousins), and the many native northeast maples.  

A Stroll Through the Maples

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In this third edition of my blog series on some of my favourite trees and shrubs, I’m taking a meander through the genus Acer, the maples, specifically those native to eastern North America.  And what better way to start than with the spring flowers of the iconic red maple (Acer rubrum)?   Always one of the first species to show colour, this tree in Toronto’s Mount Pleasant Cemetery was sporting its fuzzy male or staminate flowers on its bare branches on March 31, 2010…

…. with a closer look here.  Red maple flowers are an important early source of pollen and nectar for native bees, hoverflies (like the one below) and honey bees.

Red maple trees, sometimes called “swamp maple” for their propensity to grow in damp sites, are generally dioecious with male and female flowers on separate trees, but occasionally a tree will contain flowers of both sexes, but on separate branches. Some trees have even been seen to fluctuate yearly between male and female flowers – something botanists call gender inconstancy.  This article titled ‘The Sex Life of the Red Maple’ by population biologist Richard Primack in Harvard’s Arnoldia magazine recalls that this gender variation has been called a “polygamodioecious” breeding system. Female or pistillate red maple flowers look like dangling, ruby-red earrings with their curved stigmas.  I photographed these April 9, 2010.  

I found our spring-flying polyester or cellophane bee (Colletes inaequalis) foraging for nectar in red maple flowers on April 22, 2016.  However, the length of the stamens and stigmas has suggested to botanists that some red maples may also be wind-pollinated, i.e. not entirely dependent on insects for reproduction.

When I hike through the 4700-acre Torrance Barrens (my local ‘sacred place’ on Lake Muskoka) in early spring, it’s always a joy to see the red maples, their red flowers contrasting with the rugged, grey gneiss outcrops.

And at our own cottage property in Muskoka, I only have to look out the window to see one of our own wild red maples coming into bloom alongside its faithful companion, the white pine (Pinus strobus).

Red maple leaves are green in summer as they absorb sunlight to synthesize the sugars the trees need to survive.  The species is well-known for being intolerant of alkaline soils, and leaves often appear “chlorotic” or yellowish in those conditions. The particular array of the leaves in the canopy is often reflected in its autumn colour, with more exposed parts of individual leaves turning red, while shaded portions turn yellow. 

The winged fruit or seed key of all maples is called a ‘samara’.

The red maple below in Section J in Mount Pleasant Cemetery is one of my favourite trees in autumn.  You can see some of that mixed fall colouration here….

…. and also below in my arrangement of leaves I picked up below another tree. Notice how different these leaves are from the green ones above and others later in this blog. Red maple is known for having a wide diversity of leaf shapes.

The tree has been a sentimental favourite of writers and naturalists. In his journal, Henry Thoreau wrote this on September 25, 1857:  “The red maple has fairly begun to blush in some places by the river. I see one, by the canal behind Barrett’s mill, all aglow against the sun. These first trees that change are most interesting, since they are seen against others still freshly green — such brilliant red on green. I go half a mile out of my way to examine such a red banner.”

But some red maple cultivars have been selected specifically for their biochemistry in producing a reliable show of red fall colour, like the tree below (possibly Red Sunset) which has carpeted the ground in the cemetery after an overnight freeze.

Contrast that uniform colour with the leaves of the straight species, below.

In fact, there are so many mature red maples in the cemetery that I have photographed specimens featuring all-gold, all-yellow and all-red fall leaves, below. Note the serrated margins of the leaves – an easy way to tell red maple from sugar maple, which has smooth margins.

Here is a side-by-side comparison of two large red maples in autumn.

At our own cottage on Lake Muskoka, I photographed young red maples at the shore exhibiting this same colour difference.  Things like this are interesting to me because there is a general theory that (red) anthocyanin secondary pigments act as autumn sunscreens for certain tree species, allowing them to continue to photosynthesize well into the fall after green chlorophyll breaks down.  Despite my efforts, I have not been able to ascertain why there is such startlingly different pigment biochemistry in this species, particularly when grown on the same plot of land where pH is not therefore a factor. My own theory, backed up by a few speculative references, is that it has to do with sex of the tree: red leaves on males, yellow leaves on females. (Oh, by the way, voracious local beavers cut down these scrubby little red maples.  Beavers don’t care about biochemistry, only housing.)

Speaking of the cottage, this is our best red maple in autumn, as seen from indoors. (And that’s my homemade botanical lampshade.)

It doesn’t surprise me that Acer rubrum is considered to be the ‘most abundant and widespread deciduous tree species’ in eastern North America.  If you hike in our local Muskoka, Ontario woods in May, the little seedlings appear everywhere, including with spring ephemeral wildflowers such as trout lily or dogs-tooth violet (Erythronium americanum), below.  This photo is also a good illustration of the “opposite branching” habit of all maples.

Here it is amidst wild strawberries (Fragaria virginiana) and other native plants.

In the same forest, on the same day, we find a sugar maple (Acer saccharum) seedling.  Note the smooth margins and the opposite branching.

Sugar maple’s flowers are unlike those of red maple; they are ‘perfect’, meaning male and female flowers are on the same tree. Here you see mostly male flowers with their dangling anthers, but also a few female flowers with the curved stigmas.  Sugar maple also flowers later than red maple.

In autumn, sugar maple trees colour early, often with salmon-scarlet leaves covering an entire tree but sometimes with many hues at once, as you see below in my photo from Mount Pleasant Cemetery. 

Between them, red maple and sugar maple produce the most vibrant autumn colours in northeastern forests. One year, a relative with a small plane took me up above the forests of Muskoka. Looking down, this is what I saw:  a spectacular combination of red maple and sugar maple, with birches and aspens offering yellow contrasts. Oaks would change colour later.

In the ravine in the park at the end of our street in Toronto, the population of native sugar maples, in fall colour below, struggles to survive against the incursion of exotic, invasive Norway maple (Acer platanoides), at right. That European maple takes on yellow fall colour later, along with its normal coal tar spot disease which is visible on some of the leaves.

On the boulevard in front of the pollinator garden at our house in Toronto, we have a columnar tree that I ordered as “red maple” with its presumably spectacular fall colour, to go along with the ginkgo at right. Imagine my disappointment when those red leaves turned out to be dishwater yellow.  Across the street is a Freeman maple – more on that one below.

The ginkgo and red maple on my boulevard were replacements for the 100-year-old silver maple (Acer saccharinum) tree that had dominated our view and given us shade for all the years we’d lived in our home… until 2007. That’s when the city’s water department came through the neighbourhood upgrading the plumbing. I looked down from my 2nd story windows at the workers having their lunch one day.

After they went home, I looked at the excavation on the boulevard. How could any tree survive the kind of root cutting that this would involve?

Sadly, it did not survive (though silver maples are considered short-lived compared to other native trees.) In 2011, it received the dreaded orange dot that designated it for removal.  But note the weeping area in the bark; this is called ‘bacterial wetwood’ and is caused by bacterial infection of a wound.  It happens to many trees and does not bode well for them.

Silver maple trees usually bear male and female flowers separately, but can also have ‘perfect’ flowers containing both male and female organs, like the one below where you can clearly see the male anthers and female stigmas.

Healthy silver maples (they can be notoriously weak-wooded) reach a considerable size at maturity, up to 90 feet (27 m) or more. Native to a wide swath of the Northeast and Central Plains from New Brunswick and Maine to Minnesota and eastern Oklahoma and Texas, they are generally bottomland trees, preferring moist soil.  They derive their common name from the silvery underside of the leaves. In autumn, the foliage turns pale yellow. 

Compared to red maple, silver maple leaves are narrow and very deeply notched.

There is an attractive, naturally-occurring hybrid of red and silver maples called Freeman maple (Acer x freemanii). Named in 1969 for Oliver Myles Freeman (1891-1979) of the U.S. National Arboretum……

…… who made the first controlled cross of the species in 1933, using red maple as the female parent, it blends the best traits of both species: the form and rich fall colour of red maple with the fast growth and cultural adaptability of silver maple.

Growing 40-60 feet (12-18 m) tall with a 20-40 feet (6-12 m) spread, it has become a popular street tree in Toronto.  There are also many specimens at Mount Pleasant Cemetery, below.

When I created my “leaf dancers” blog in November 2020 (see Pigments of my Imagination), I gathered small Freeman maple leaves from the boulevard tree across the street to fashion the skirts of my Maple Maypole dancers.  I like to think Oliver Freeman would be amused to see them.

Finally, a little maple that grows in the shady understory of northeastern forests, including the mixed woods near our cottage on Lake Muskoka:  striped maple (Acer pensylvanicum).  It’s also called “moose maple” because it is sometimes the winter food of moose and white-tailed deer; squirrels and chipmunks forage on its twigs; and many birds consume the seeds. Though occasionally seen as a small, single-trunked tree, it is usually found in nature as a multi-stemmed shrub, seldom exceeding 20 feet (6 m).  Taxonomically, it is the only non-Asian species in the Acer section Macrantha, or “snakebark maples”; all the other 18-21 species, e.g. A. davidii, A. rufinerve, A. tomentosum, occur in China, eastern Russia, Korea, Japan or Myanmar.  The photo below shows its dainty samaras.

Its leaves have three shallow lobes and the greenish flowers are held in arching racemes.  If you look very closely, you can see an early instar of gypsy moth or LDD moth (Lymantria dispar dispar) on the lower right of the leaf. In May, I still thought we’d survive the onslaught of this destructive pest; by mid-summer, it was clear we had not, as you can read in my 2021 blog.

Though there are other maple trees in North America, including mountain maple (A. spicatum), Manitoba maple (A. negundo) and black maple (A. nigrum) in the east and central Canada and bigleaf maple (A. macrophyllum), Douglas maple (A. glabrum subsp. douglasii) and vine maple (A. circinatum) in the west, I’ve included in this stroll the beautiful trees I see each year here in Ontario.  Oh, there’s one more maple we see fairly often – and it’s native right across the country.  My little granddaughter once confused it with the phrase “make believe”, but it is our true (if slightly stylized) “maple leaf forever”.

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Want to read about more North American trees?  See my recent blogs on tuliptree (Liriodendron tulipifera) and redbuds (Cercis canadensis and its cousins). And here is one on fall colour in Mount Pleasant Cemetery.

Radiant Redbuds

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In my second blog looking at trees native to eastern North America, I’m focusing on a crowd favourite: eastern redbud, Cercis canadensis (as well as a few of its overseas cousins). One of my great botanical thrills was driving through North Carolina in early spring 2003 and seeing the spectacular combination of flowering dogwood (Cornus florida) with redbud in the woods along the highway. This photo from my slide film days shows these two native partners at their flowering peak.

I wish I could say that eastern redbud is native to Ontario, but that is not the case unless you count a reported single sighting in 1892 by botanist John Macoun of a tree on the south shore of Pelee Island (which is itself the most southerly piece of land in Canada). Nevertheless, redbuds grow very well in gardens in southern Ontario, particularly if they’re sourced in Michigan where their hardiness is more assured than those from more southern climes. They reach about 30 ft (9 m) in height and spread. That considerable width, especially, means they’re not always the best choice for a very small garden, though they can be pruned to maintain the desired shape. I love the redbuds that grow at Toronto Botanical Garden, below.  

Redbud is from the legume family, Fabaceae, so its magenta-pink flowers resemble its familiar cousins like sweet pea, lupine and runner bean. In a good year, the clusters literally cloak the branches.  Like many other legumes, the flowers are ‘papilionaceous’, from the Latin papilion for butterfly and describing the shape of the corolla. They are also ‘cauliferous’, meaning they emerge directly from the branches before the leaves are produced.  But unlike many other legumes which bear compound leaves, redbud leaves are simple and heart-shaped.

Redbud flowers are edible, rich in Vitamin C and especially good in salads. According to Mother Earth News, they “have a delicious flavor that is like a green bean with a lemony aftertaste”. They are also excellent sources of nectar and pollen for early bees, and used by native bees like this cellophane bee (Colletes inaequalis) in Toronto…..

…. and also honey bees (Apis mellifera), provided temperatures are warm enough for them to fly. This one was near the hives at the Toronto Botanical Garden.

There is a white-flowered form (C. canadensis f. alba) which looks especially beautiful when planted amidst pink-flowered redbuds.

It is also popular with bees, like this bumble bee queen.

At the Toronto Botanical Garden, there is a lovely raised copse of assorted redbuds underplanted with spring bulbs.

Cascading over the stone wall in the photo above is C. canadensis ‘Covey’ or Lavender Twist™, a small, weeping eastern redbud found in Cornelia Covey’s garden in Westfield, NY in the 1960s and propagated and patented by Tim Brotzman. It is perfectly placed in this garden, below.

There are several good cultivars of eastern redbud, if your taste runs to coloured foliage. ‘Forest Pansy’ is one of the oldest. Found originally in 1947 at Forest Nursery in McMinnville, Tennessee, it was patented in 1965.  In spring and early summer it is a rich, wine-red, but I love standing under it later in the season when it has lost some of its red anthocyanins pigments and takes on this mottled look.

‘Ruby Falls’, below, is a cross between ‘Covey’ and ‘Forest Pansy’. It’s a small tree, 6 ft (2 m) tall and 4 ft (1.3 m) wide.

I photographed luminous C. canadensis ‘Hearts of Gold’ at wonderful Chanticleer Garden near Philadelphia, my very favourite garden in the U.S. (If you haven’t been to Chanticleer, have a read of my 2-part blog starting here.)  ‘Hearts of Gold’ with its large, chartreuse-yellow leaves was discovered in spring 2002 in Greensboro, N. Carolina by Jon Roethling (now director of Reynolda Gardens in Winston-Salem).   

When I was visiting the United States Botanic Garden in Washington DC in June 2017, I was entranced by the beautiful foliage of Cercis canadensis ‘JN2’ or Rising Sun™, below. Long past flowering, I was treated to the sight of apricot-orange emerging leaves, changing to yellow, then chartreuse, then dark green.  With a 12-ft (3.6m) height and 8-ft (2.4m)  spread, this redbud was found in 2006 and introduced by Ray and Cindy Jackson of Jackson Nursery in Belvedere, TN.

The abundant fruit pods of redbuds are called ‘siliques’, from the Latin word siliqua, meaning a pod or husk. It is defined as a long dry, fruit (seed capsule) with its length measuring more than twice the width, consisting of two fused carpels that separate when ripe.  I found the eastern redbud, below, loaded with seedpods in Toronto’s Mount Pleasant Cemetery one August.

This is that same tree in the cemetery in autumn, showing off its bright yellow fall colour.

There are two other varieties of North American redbud:  Texas redbud, C. canadensis var. texensis and Mexican redbud, C. canadensis var. mexicana.  I found the latter with its frilly, circular leaves and deep-pink ‘siliques’ at the University of California Berkeley Botanical Garden.

The native European redbud is Cercis siliquastrum from the Mediterranean, its Latin specific epithet chosen by Linnaeus to denote those siliqua.  When I was on my wonderful botanical tour of Greece in autumn 2019, I found redbuds putting out a second flowering in Thermopylae, scene of the historic 480 BC battle between the Persians and Spartans.    

And I found it flowering in the pouring rain in the countryside in Attica.

On a long-ago trip to Paris, there it was in the garden of the Tuileries, below.

Back to North America, I was visiting the Santa Barbara Botanical Garden in March 2014 and was delighted to capture an Anna’s hummingbird (Calypte anna) nectaring in the flowers of the western redbud (Cercis occidentalis).  This is usually a multi-stemmed shrub and about half the size of eastern redbud and the leaves are more round.

Honey bees were enjoying the western redbud flowers as well.

I found Chinese redbud (Cercis chinensis), below, at RHS Wisley in England way back in 1992. Although it is listed as much taller (49 ft or 15m) than eastern redbud, it evidently usually grows in the wild as a multi-stemmed shrub.

While visiting Van Dusen Botanical Garden in Vancouver in May 2014, I found C. chinensis ‘Avondale’ in flower in their Asian collection.  A fairly small tree introduced by Duncan and Davies Nursery in Avondale, New Zealand, it grows about 10 ft (3m) tall x 6 ft (2m) wide.

On May 4, 2019, I photographed a dense, multi-stemmed shrub labelled Cercis gigantea at the late plantswoman Francisca Darts’s garden, Darts Hill Garden Park in Surrey, B.C. (below).  In ‘Trees and Shrubs Online’, authors Ross Bayton and John Grimshaw write: “This species is enigmatic. There is no record of the publication of the name in either the International Plant Names Index (www.ipni.org) or the International Legume Database & Information Service (www.ildis.org), and it is not described in the (currently draft) Flora of China treatment, and yet it appears in the catalogues of several nurseries and botanic gardens…. The limited information available via the internet suggests that C. gigantea is similar to C. chinensis but has much larger leaves and a more vigorous growth rate. Plants originating from seed collected as C. chinensis during the 1980 Sino-American Botanical Expedition ( western Hubei) were later identified as C. gigantea by Dr Ted Dudley at the US National Arboretum…. supporting this supposition of similarity between the two taxa.”

I will leave you with my photo of eastern redbud in the Japanese Garden at Denver Botanic Gardens from April 28, 2018, and the words of naturalist Donald Culross Peattie — always the romantic — from his ‘A Natural History of Trees of Eastern and Central North America’.  “When the redbud flowers, the still leafless deciduous woods display its charms down every vista; it shines in the somber little groves of Scrub Pine; it troops up the foothills of the Appalachians; it steps delicately down towards swampy ground in the coastal plain, flaunts its charms beside the red clay wood roads and along the old rail fences of the piedmont. Inconspicuous in summer and winter, Redbud shows us in spring how common it is.”