Ottawa

Historic Parliament Hill elm lives on in rescued saplings

More than a month after it got the axe, Parliament Hill's historic elm tree will live on thanks to ten saplings saved by the Elm Recovery Project in Guelph, Ont.

Around 100 twigs were sent to University of Guelph to breed new trees

This elm tree on Parliament Hill was chopped down in April. Before it was removed, however, a number of twigs were sent to the University of Guelph in the hopes they could one day be grafted and replanted. (Hallie Cotnam/CBC)

More than a month after it got the axe, Parliament Hill's historic elm tree will live on in some young saplings.

The century-old American elm was cut down in April, despite pleas to keep the majestic tree that grew beside a statue of Sir John A. Macdonald alive during major Centre Block renovations.

Around 100 twigs cut from the tree in March ended up being sent to the University of Guelph's arboretum as part of its Elm Recovery Project.

The twigs were between five and 10 centimetres long, and were sent overnight in coolers to the arboretum.

Of those, 50 made the cut for the grafting process.

Out of around 100 twigs that were sent to the University of Guelph, ten survived the grafting process to become baby saplings. (Sean Fox/University of Guelph)

"We're looking for healthy plump twigs with good buds and trying to match up the sizing of them as best we can to the size of the rootstock that we have," said Sean Fox, manager of horticulture and curator at the University of Guelph Arboretum.

The best twigs have three or four buds, Fox said, making it more likely for the buds to break open and turn into new shoots and leaves.

We were actually quite thrilled to have 10 of them survive and make it.- Sean Fox

"We cut the twigs into a specific shape and form that allows us to insert them into the seedling rootstock and we bind them up," he said.

They're then kept in a kind of "intensive care" unit for trees for a few weeks, with regulated humidity and temperatures, so their "wounds" can heal.

The twigs came to the centre late in the season, since grafting is normally done in February, Fox said. Because of the elm tree's age, most were dried out and not in great shape.

Parliament Hill's grand old elm tree is gone. But its genes live on. What happened once horticulturalists from the Elm Recovery Project got their hands on cuttings from the lost elm. 6:05

"We were actually quite thrilled to have 10 of them survive and make it," Fox said. "And they've put on several inches of growth already and are looking very healthy and very vigorous."

The saplings will be cared for in a greenhouse before they're big and strong enough to be released into the world, most likely somewhere in Ottawa.

The grafting process involves cutting the twigs into a specific shape and form to insert them into the seedling rootstock. (Sean Fox/University of Guelph)

Elm killer

Elms were abundant across Ontario at the beginning of the last century, but then Dutch Elm Disease made its entrance into the country, killing millions of trees.

The Asian fungus (named after a Dutch pathologist) was first discovered in Quebec in the 1940s before spreading across Ontario in the late 1950s to 1970s, decimating the elm population — only one to two per cent survived. 

It's primarily spread by the elm bark beetle, but a tree can be infected if a saw is used on a sick tree and then on a healthy one.

Whether trees that survive are immune or simply lucky is part of what the Elm Recovery Project tries to determine. Since many elms don't survive past 30 or 40 years old when the fungus hits, the Parliament Hill elm tree was particularly rare, Fox said.

Fox said the University of Guelph is trying to preserve elms that seem to have persevered through the disease. Whether the Parliament Hill tree survived, however, because of its genetics — or because it had help from fungicides provided by caring gardeners over the years — is still unclear.

What is clear is that now that the 10 saplings have survived, the genetic profile of the historic elm will survive and be used to create more elms.

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