Cana­di­ans asked to find na­tive ash trees

Col­lec­tion of seeds part of bid to pre­serve species

The Peterborough Examiner - - Canada & World - MICHAEL MAC­DON­ALD

HAL­I­FAX — An in­va­sive insect from Asia is ex­pected to kill al­most ev­ery ash tree in Canada, but Don­nie McPhee has a plan to pre­serve the species.

Co-or­di­na­tor for the Na­tional Tree Seed Cen­tre in Fred­er­ic­ton, McPhee is ask­ing Cana­di­ans to help him find ma­ture stands where seeds can be gath­ered and later stored for fu­ture gen­er­a­tions in the cen­tre’s deep-freeze vaults.

“We’re look­ing to pro­tect the ge­netic di­ver­sity of the species,” McPhee said in an in­ter­view. “We’re look­ing for nat­u­ral stands of trees that are in seed ... We want Cana­di­ans to be our eyes — to let us know they’re out there.”

And the time is right to start the search be­cause the white ash and black ash — two of the most com­mon species — are ex­pected to pro­duce a bumper crop of seeds this fall. The cen­tre’s web­site pro­vides de­tails on what to look for, but seed col­lect­ing should be left to ex­perts.

“We’ve al­ready had peo­ple show­ing up with big bags of ash seed ... but it’s too early in the sea­son,” McPhee said.

Lar­vae of the emer­ald ash borer, a small bee­tle with an iri­des­cent green hue, have al­ready killed mil­lions of trees in Canada and the United States, and the pest’s pop­u­la­tion is still grow­ing.

The lar­vae make tun­nels un­der­neath the tree’s bark, cut­ting off nu­tri­ent flow to the canopy, which even­tu­ally kills the tree.

“The re­ports I’ve seen sug­gest that within 50 years, there might not be any ash trees any­where in the coun­try,” McPhee said.

In Wind­sor, Ont., where the bee­tle was first de­tected in 2002, more than 90 per cent of the ash trees have al­ready died.

The insect, known to hitch rides on ships, trucks and cars, has also been found across south­ern On­tario, south­ern Que­bec and in the New Brunswick com­mu­ni­ties of Ed­mund­ston, Oro­mocto (near Fred­er­ic­ton) and, as of last week, Monc­ton.

It was spot­ted last year in Win­nipeg and in Bed­ford, N.S., where Nat­u­ral Re­sources Canada has de­ployed ex­per­i­men­tal traps filled with a bee­tle-killing fun­gus.

The range for Canada’s most com­mon na­tive ash species — white, black and green ash — stretches from Nova Sco­tia, across New Brunswick and to the south­ern reaches of On­tario and Que­bec.

How­ever, black ash can also be found in western New­found­land, northern On­tario and east­ern Man­i­toba. And green ash — the most wide­spread species — can also be found in south­ern Man­i­toba, south­ern Saskatchew­an and south­east­ern Al­berta.

Though ash trees are not na­tive to much of Al­berta and Bri­tish Columbia, non-na­tive trees have been planted in many cities across Canada, cre­at­ing a lush ur­ban canopy that is now un­der threat.

Jon Sweeney, a re­search sci­en­tist with the Cana­dian For­est Ser­vice, said the loss of ash trees also means the loss of the 44 species of in­sects and other or­gan­isms that de­pend on this par­tic­u­lar type of tree.

“When the ash trees go, you lose more than the trees,” said Sweeney. “You get com­pli­ca­tions.”

As well, the dead ash trees may be re­placed by in­va­sive plants, which has al­ready hap­pened in the United States.

McPhee’s long-term plan is to have the cen­tre re­trieve the col­lected ash seeds from cold stor­age in about 40 or 50 years, when the ash borer pop­u­la­tion has dwin­dled and safe plant­ing can be­gin.

“The pop­u­la­tion of the insect will drop way down be­cause the food sup­ply isn’t there,” he said. “At that time, we want to go in and put the ge­netic di­ver­sity of the pop­u­la­tion back to where it came from.”

STEPHEN MACGILLIVR­AY THE CANA­DIAN PRESS

Don­nie McPhee, co­or­di­na­tor of the Na­tional Tree Seed Cen­tre of Nat­u­ral Re­sources Canada, says that within 50 years, there might not be any ash trees left in Canada.

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