Tree Tuesday: Stalking the Walnut: 3 Sites

Walnuts are trees of the Gods. It’s right there in the name: Juglans means the nut, or acorn (as in the French, gland), of Jupiter, top God of the Romans. And the tree carries itself like royalty, spreading its long, strong branches almost as wide as high. Think of the tallest tree in the Redpath Dell, the hollow immediately to the east of the Redpath Museum on the McGill University campus. What you see here in this photo are the fruit of the black walnut (Juglans nigra, Noyer noir).  The edible nut is within the shell encased in this lime green husk.

But this is not the fruit of the great walnut of the McGill campus, circa 1882, nor of any other establishment of 19th century, institutional Montreal. I took this photo yesterday in a post-industrial vacant lot. Not the sort of place you expect to find the regal Juglans, a tree that in this part of the world generally needs good soil and a certain amount of pampering, being a little north of its usual territory in Canada, which is the Carolinian zone of southwestern Ontario. So, what was Jupiter  doing in the Mile End Meadow (my name for the old Canadian Pacific railyard where Henri-Julien street meets the tracks, across the street from the Carmelite Monastery), growing amongst such hobos as the cottonwood poplar, sumac and Manitoba maple?

It’s easy to identify the source of the original nut planted, from which this walnut — and its numerous sibling trees in the vicinity — sprang. When I first began frequenting this meadow, in preparation for a guided tree walk, I could see that many of the tree species originated in the Carmelite garden where there is an orchard of fruit trees and numerous century old broadleaf trees, including silver maples, honey locusts and … an enormous black walnut.

Clearly, squirrels had crossed the Great Wall and planted the fruit. Still, I was mystified by the location of the five or six young trees I had spotted, all growing on the periphery of the field, along one wire fence or another. One morning last fall, waiting for my group to arrive, I sat quietly and observed a squirrel with an enormous — at least relative to the size of the squirrel — walnut in its mouth. After crossing Henri-Julien street, it dashed to the nearest bit of metal, mesh fencing. Squirrels don’t like to travel on the ground; there are too many potential predators, such as dogs, and their short legs aren’t meant for tall grasses. Fencetops, therefore, comprise an important element in their channels of transportation.

The Mile End Meadow (MEM) is fenced, in intervals, by several long stretches of Frosst fence, and I watched as the squirrel traveled adeptly along the fencetops with the large load in her mouth. Finally, I lost sight of her at the end of western stretch of fencing, a point where there just happens to be a trio of young walnuts. So, I surmised, the squirrel either drops the fruit at the end of the fence or buries it there. And, given that the lawnmowers, which periodically  trim all that grows in the field, including young trees, can’t get too close to the fence, the walnuts — and numerous other plants — thrive within the grace of the margins.

Of course, it’s not only the mowers that can’t get too close to the fence, it’s the walkers and cyclists too. So, all the vegetation that grows close to  fences, and buildings too, have a greater chance of survival than those in open. What’s good for the squirrel is good for the walnut.

I am fascinated  by the self-seeding trees, those that “escape from gardens,” as we say. None, of course, escape on their own except those whose roots pass under fences and walls and send up new shoots, such as sumacs and black locusts. The self-seeders, are, in fact, seeded either by wind, water, birds or mammals. They depend on disturbed, open soil in which their seeds may fall or –in the case of the animal-seeded — be buried. At this time of year, for instance, in my alley near des Pins and St-Denis streets, there are always a few cottonwood seedlings, sent by the wind from the next alley over where a Titanesque lady cottonwood literally casts her fate to the wind in the form of millions of tiny seeds attached to threads of cotton-like fibre. So far, none have survived more than the summer. There is likely too much competition in the narrow line of opportunity where the curb meets the asphalt.

In the case of the Mile End Meadow and the surrounding parks and gardens, it’s easy to see how biodiversity begets biodiversity: the more food there is for the squirrels and birds (ckokecherries, samaras from the maple, elm and ash trees, and, of course, the walnuts) the more squirrels and birds there are, the more the various seeds are distributed, etc. In addition, the great variety of herbaceous (non-woody) plants in the meadow provide nectar and pollen for a variety of insects which, in turn, feed the birds, and the cycle goes round.

The trees also provide shelter, or habitat, for the birds and mammals which, again, facilitates the expansion of biodiversity. I can well imagine Nicolas, as the enormous cottonwood in the centre of the meadow has been named by the Mile End tribespeople, housing a  family of racoons in the not too distant future.

To return to the black walnut, I discovered another marginal specimen growing, this time, from the angle between the ground and the brick wall of a former McGill University residence on the northwest corner of McTavish and Dr. Penfield streets. It’s already bearing its own fruit, meaning that the tree must be close to 10 years. I try to imagine the squirrel making its way from the Redpath Dell across the traffic of Dr. Penfield, the bright green globe in it jaws. On the other hand, the squirrel might well have descended from the heights of the Lady Meredith House grounds, on the west side of Peel Street at Pine Avenue, where there are several old black walnuts.

What is interesting about the walnut is that while the mother-father (walnuts are hermaphrodite trees meaning that the male (pollen) and female (seed) flowers are on the same tree) individuals  were planted deliberately for their grandeur and their fruit by those associated with either the well-to-do or with the church, 100 years later, their offspring are happy to mix with the commoners.

Another site where on might expect to find a black walnut is at the original entrance to Parc La Fontaine, on the southeast corner of de La Fontaine and Rachel streets. This is the former site of Montreal’s municipal greenhouses, where the plants for city squares were cultivated. The massive ginkgo (Ginkgo biloba) and small-leaf linden (Tilia cordata, tilleul à petites feuilles)  at that corner were likely planted when the greenhouses were opened in 1889. Such trees were fashionable at the time, much like the black walnut.

I haven’t found a record of black walnut having been planted but there are plenty of young white walnut, better known as butternut (Juglans cinerea, noyer cendré) growing in the area just to the east of the Félix Leclerc monument. Here, you can see how the butternut fruit is more elongated than that of the black walnut:

This is our native walnut and its leaflets are slightly wider than the black walnut and it has a well-defined terminal leaflet which the black walnut lacks. Curiously, I have never found a self-seeded butternut and I wonder if it doesn’t need richer soil or, perhaps, it simply produces less fruit  than the black walnut. Sadly, this trees, whose nut is delicious and was widely used by First Nations and early European peoples in eastern North America, has been hit by a fatal fungus, and is  an endangered species. Nevertheless, lovely, old butternuts are still found on the McGill grounds and at a few spots along Côte St-Antoine Rd., in Westmount, once an Iroquois walking trail, and, no doubt, in numerous other parts of Montreal where there are still vestiges of old farms or forest.

During my upcoming tree tours, we will be identify both our local walnuts as well as numerous other species. The Mile End Meadow walk will be led by me, Roger Latour, author of Guide de la flore urbaine and the blog Flora urbana, and Susan Bronson, architect and historian of Mile End. Emily Rose Michaud, who by the creation of her Roerich Garden in the middle of the Mile End Meadow, brought the magic of meadow to many, will also be there.

Two walks: 1)Sunday, July 19, 14h – 16h, Mile End Meadow, meet corner Henri-Julien and des Carmelites streets (just south of railway tracks); 2) Wednesday, July 29, 17h30 – 19h30 Parc La Fontaine, meet corner Rachel and de La Fontaine.

$12 per walk or three walks (at any time during 2009) for $30. Half of all proceeds for Mile End Meadow walk go to the protection of the meadow.

Reservations: bronwynchester@gmail.com OR 514-284-7384