NATURAL HISTORY

By

Ian and Kate MacQuarrie

They ALL Came From Away

A few thousand years ago this Island was nothing notable, just

bare rock and sand. The ancestors of plants and animals that we now consid-er normal scenery, our present crops, pests, diseases and peoples, all had to wend their weary ways, by accident or design, to their new home. Since the time-scale is so short, priority of arrival should be of no great consequence to anybody except the historian — partic-ularly since population change and movement are biological norms. However, sometimes a species may succeed in arriving well in advance of its natural competitors and enemies. With this head start and a good cli-mate it may outstrip its predators, evade diseases and parasites, thrive in a more congenial home. With subse-quent human habitat disturbance (and particularly on islands) there is also the possibility of an empty niche — an

open, unexploited way of making a liv-ing. If conditions are right, such an exotic species may expand its num-bers and range with explosive rapidity. Sooner or later the human population notices. And often becomes alarmed.

Any "come-from-away" may be prized or despised, frequently for no obvious reason. We protect the eagle but still attack its fellow-scavenger, the raven. We disparage the skunk and hunt the raccoon: defend the piping plover but ignore our threatened amphibians. Such irrational actions are extended to the plant world as well: we coddle some orchids while trampling others, coo over lupines while unloos-ing a torrent of abuse at the equally-interesting (and probably less toxic) loosestrife. Humanity's approach to nature thus seems to be one of perpet-ual interference, often for ill-consid-ered reasons.

As examples, consider two colourful exotic plants now well established in

the local flora: Big-leaf Lupine (Lupinus polyphyllus) and Purple Loosestrife (Lythrum salicaria). These are easily found and identified; both occur commonly in ditches, thus not requiring arduous collecting treks over difficult ground. They are garden-adaptable, although your neighbours may disapprove if you show a taste for loosestrife, perhaps muttering about the "purple plague." Finally, these are invasive species, arriving here relative-ly recently, quietly blooming for a few decades, then taking off to sweep over the whole Island. They are thus most appropriate plants for botanical (and societal) lessons.

Dealing first with the more socially-acceptable lupine, our local model is but one of hundreds of North American species. Several are impor-tant in agriculture, but our familiar specimen is probably a garden escape. Horticulturalists have created many hybrids (Russell lupines, Harkness

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Big-leaf lupine (lupinuspolyphyllus).

hybrids, etc.) with flower colours vary-ing from white to dark blue; probably it is the mix of these colours in mas-sive amounts that has led to public acceptance of this invasive weed. Erskine notes that it has been here since 1912 at least, spreading from cemeteries along roadsides. In earlier years farmers regarded this plant with some suspicion, since it can invade

poor pastures and may under some circumstances be toxic. Agriculture Canada points out that it produces nasty alkaloids which can cause devel-opmental defects in cattle, although documented cases are hard to find. Now that tourists rather than cattle graze our roadsides perhaps the dan-ger is not so great, and certainly its presence has been a boon to Kodak;

without question this is the most pho-tographed plant on the Island.

With the Island's extensive road system, ditches are a significant land-scape feature. They are not just water conduits and litter-traps; they provide habitat and transit avenues for many plant and animal species. Curiously, lupine-induced changes in ditch ecolo-gy have received little or no unbiased attention. What more attractive, inter-esting, uncommon, useful plants are being choked by this invader from the West Coast? Is there an impact on the fly-catching Sundew (Drosera rotundi-folia)? What little birds go hungry since they cannot digest big, disagree-able lupine seeds? How is small mam-mal life and movement affected? We haven't looked closely; we do not know. Indeed it is clear that people have actively encouraged lupine spread by collecting seed, then scat-tering it along roads in blithe disre-gard for other ditch inhabitants. The tourist literature extolls "lupine trails" and local society seems to regard the resulting banal colours with benevo-lence. We have not yet come to believe that the Island's well-being depends upon waging war on lupines.

Such is not the case with loosestrife. "Purple plague" is one of the kinder descriptions given to this aggressive species. Many jurisdictions have declared loosestrife to be a noxious weed, and control methods such as cut-ting, herbicide application, water level manipulation have been tried, usually with minimal success, for many years. In early 1997 the United States intro-duced the ultimate bureaucratic weapon: formation of the delightfully-acronymed Invasive Weeds Awareness Coalition or IWAC. This organization is dedicated to raising a particular kind of awareness: invasive weeds are an enor-mous threat to our civilization. They must be attacked with the bureaucratic equivalent of smartbombs — public relations campaigns. "Non-native inva-sive plants are far more than an agricul-tural problem, they're an environmental one," warns one 1997 press release "Because of this ecological and eco-nomic threat we must act now on a national level to combat this cancer on our landscape."

Declarations of war by press release seem to be common reactions to most little-understood natural phe-nomena; we have battlefield reports from wars against drugs, floods, mad

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Family

Genus

Species

Canadian Distribution

Habitat

Appearance

Lupine

Fabaceae (or Leguminosae), or Legume Family, which includes about 75 gen-era.

Lupinus, from the Latin for wolf. This name reflects a belief that because lupines are found on poor soil, they steal (or "wolf") minerals from the land.

polyphyllus= many-leaved. However the common name for Lupinus polyphyllus is 'Big-leaf lupine'.

In Canada, British Columbia, Ontario, Quebec, and the Maritimes.

Poor, dry soils: roadsides, ditches, sometimes old fields.

A perennial over 1.0 metre high with palmately compound leaves. Flower colour varies from creamy white to deep purple; flowers are carried on a spike at the top of the plant. In autumn pea-like seed pods form.

Loosestrife

Lythraceae, the Loosestrife Family, includes about 20 mostly tropical genera.

Lythrum, from the Greek for black blood. Very likely a reference to the plant's deep purple flowers. The loosestrife' is perhaps a reference to this plant's medicinal uses, or to King Lysimachia of Thrace.

salicaria = willow-like. Reference to leaf shape.

Found in all Canadian provinces. On Prince Edward Island, wetlands in all three counties. (See map).

Wetter soils: ditches, fresh marsh-es, wet meadows, along rivers & ponds.

A perennial up to 1.5 metres high with narrow, pointed leaves oppo-site each other along the stem. Each plant consists of many dozens of stems. Flowers are a vivid purple in a tall spike .

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

North Lake Bothwell Selkirk Howe Bay Mount Hope St. Peters Seven Mile House Brudenell Valleyfield French Village Blooming Point

12. Mount Stewart

13. Fort Augustus 14. Bethel 15. Southport 16. Charlottetown 17. Nine Mile Creek 18. Canoe Cove 19. New Dominion 20. Milton

21. Clyde River 22. New Haven 23. Cornwall 24. Argyle Shore 25. Pleasant Grove 26. Hunter River 27. Churchill

28. York 29. Covehead 30. Brackley 31. Mayfield 32. Albany 33. Summerside 34. St. Nicholas 35. Tyne Valley

36. Portage 37. Coleman 38. West Point 39. Woodstock 40. Bloomfield 41. Miminegash 42. PEI National Park

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Jlflpri -4- i. - '-/-

Lupine seed pod.

cows and punk rock filling the media daily, to cite only a few from a lengthy list. Must we add loosestrife to this Index? How dangerous to our Island Way of Life is this "beautiful killer?" While the literature is replete with data on control efforts, good botanical and ecological information is less easy to find.

Loosestrife has been present locally for many years. Blythe Hurst's New Flora of Prince Edward Island lists it without comment. Erskine notes that the former marsh at the Experimental Farm in Charlottetown hosted the par-ent colony; it was abundant there until 1955. It may now be found from Mim-inegash to North Lake (see map). In other areas, loosestrife has been record-ed as troublesome since the 1930s. In Quebec, for instance, it is blamed for overrunning pasture plants in flood-plains along the St. Lawrence River.

The alarm bells really began ringing in the 1980s. "A foreign invader is rav-ishing our marshlands," cried Cora

Nelson in the Conservator, "Every shal-low wetland in eastern North America is in danger," said Ducks Unlimited biolo-gist Bob Clay in the same article. This sort of comment has been reiterated so many times (particularly by Ducks Unlimited) in the last decade, that it has now become part of the accepted envi-ronmental wisdom. Schoolchildren are encouraged to attack. Gardeners and beekeepers (loosestrife is a good bee plant) are advised to mend their ways and fight this foreign menace. It is diffi-cult indeed to find a dispassionate com-ment.

There is no question that loosestrife is an invasive, spreading species, and that many reports state that it can out-compete familiar wetland plants such as cattail (Typha). It certainly does not improve the habitat for waterfowl; it is just not duck-friendly. Yet how danger-ous is it to our always-threatened wet-lands and their feathered inhabitants? Ducks Unlimited sees it as nothing less than disastrous, yet others think the threat has been overblown. In a 1995 review, Mark Anderson notes: "in con-trast to popular claims, no evidence of species declines due to purple looses-trife were (sic) found. Evidence that loosestrife out-competes cattails . . . was found to be lacking or contradictory." The scientific debate thus is not com-pletely one-sided, nor should it be.

Out on our farm, in contact with both species, we are emotional and interested observers of the lupine/loosestrife scene. We reflexive-ly call for more research and scholarly analysis on the topic of invasive plants, loosestrife in particular. We lack understanding of ditch and wetland plant dynamics, and the effects of pop-ulation change. We distrust all Task Forces and suggest that information propagated by obvious interest groups should be given rigorous propaganda tests before being widely accepted. Until such well-intentioned advice is followed, Floreat Lythruml

Note on Sources

In addition to personal observations and scientific curiosity, sources for this article include: Flora of Prince Edward Island and A New Flora of Prince Edward Island. Ducks Unlimited's stand on purple loosetrife is found in The Conservator and their internet web page, i s ! Purple loosestrife (Lythrum salicaria).

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