Saturday, April 24, 2010

Wan that Aprille with his rhubarb soote: Spring in the Home Bug Garden

Living in a transitional zone between two extremes, boreal forest and prairie, at the northern fringe of Zone 3 is always interesting, mostly in that perhaps apocryphal Chinese curse kind of way (‘may you live in interesting times’). The last few weeks, however, have been cursed only by a too strong, too persistent, and too dry wind. Temperatures have been moderate, sunshine common, the snow and ice in retreat for the moment, flocks overhead, and flies basking in the sun.

Other than flies, the first sure sign of spring in Edmonton is the appearance of the Ring-billed Gulls, cawling over the HBG sometime between 26-29 March in my records (27 March this year). The herbaceous sign of spring, as Calgary Gardening Adventures notes, is when the rhubarb shoots break ground, usually between 2-16 April in the HBG (15 April this year). So my most reliable indicators say an average spring is in the offing – a pleasant change after the last two cold and miserable ones and one the spring bulbs are relishing.
I also try to keep track of a variety of other indicator species, e.g. the Mourning Cloak (Gardening Zone 3b and Gardening with Latitude both have captured this spring treat) and Milbert Tortoiseshell butterflies. Both usually show up in mid-April, as they did this year, but you need both sun and warmth to bring them out: cloudy days are not optimum butterfly watching times. Today is a bit of a dud for butterflies. Less obvious Lepidoptera are around, though, as one can see from the margins of the variegated firespray tulip leaves.

The first bumblebee queens are on the wing and enjoying the crocus and coltsfoot, again more or less in the mid-range of my observational record. The coltsfoot, mid-range for emerging and near the early side for flowering, is doing extraordinarily well with over 20 flowering shoots up and beginning to open (vs a maximum of 8 in previous years). That means there will be a good supply of pollen and nectar in the backyard for the native bees over the next couple of weeks, and perhaps a snack or two for me as well.

Coltsfoot, more properly known as Petasites frigidus (‘Like a hat in the cold’), occurs in a variety of forms and is widely distributed across northern and western North America. You could explore some of this variety by visiting the Natural Selections exhibit at the Royal Alberta Museum, where it is on display in the botanical section. The HBG form is P. f. palmatus, or palm-leafed coltsfoot, and wandered into the HBG in a plug of forest soil salvaged from a field experiment. At the time, I had only seen coltsfoots with rather coarse, hairy leaves vaguely shaped like the print of a colt’s foot or arrowhead, so the deeply divided, rather elegant geranium-like leaves were a bit of a mystery. That mystery only deepened the next spring when thick, asparagus-like stalks bolted from the plug and covered themselves with white, composite flowerheads. The leaves appeared only much later on the wandering rhizomes far from the flower stalks, so it took me a while to figure out what was worming its way through the moist and deeply shaded bed (NB – coltsfoot will spread aggressively if it is happy).

Another name for coltsfoot is sweet butterbur and according to Linda Kershaw’s Edible and Medicinal Plants of the Rockies (Lone Pine, 2000), the flowering stalks can be eaten roasted, boiled, or stir-fried and the leaves used like fuzzy spinach. Plants for a Future also claim coltsfoot is edible (although only rate it 2 out of 5) and suggest boiling the young flower stalks before the flower buds (edible but bitter – possibly from unpleasant alkaloids) appear or munching on the peeled leafstalks. A related species, Petasites japonicus – fuki or giant butterbur – has long been used as a vegetable in Japan (and the leaves as umbrellas by children – so this is a much, much larger plant than coltsfoot). Eric Toensmeier in his informative and stimulating book Perennial Vegetables (Chelsea Green Publ., 2007), reports boiled giant butterbur stalks as being like “slightly gelatinous celery with a bit of a medicine taste”. Celery jelly? Yum, I’m sure. The alkaloids present in all Petasites are potentially dangerous too, so perhaps I’ll just enjoy the flowers and their bees and flies, and leave the culinary experience for some other time.