If Yukon grass got wiped out, what would take its place? asked UBC-based student botanist Jennie McLaren.
The answer – nothing.
In her experiment, McLaren killed off different plants and was left with nothing but soil.
“It was just dirt,” said McLaren.
Which is odd. Typically, soil patches are like New York City parking spots: they never stay vacant for long.
If McLaren had removed a tree or a shrub – and she did – some other plant would have immediately taken its place.
“But when you remove the grasses, no one else seems to be able to take up the space that they were taking up before,” said McLaren.
Grasses – nature’s meekest fauna –
seems to be more indispensable than we thought.
Everybody knows that global warming is changing ecosystems, wiping out some species and making some species more successful.
But all plants are not created equal.
A shrub is a shrub, but lose the grasses, and you lose an ecological lynchpin.
The loss of grass “would be more devastating than the loss of other kinds of plants,” read an official release by the Arctic Institute of North America.
“Some plants are more essential to their ecosystems – they control how the ecosystem works.”
McLaren originally expected that other plants would thrive when their grass neighbours were removed, sort of like how vegetables thrive when weeds are removed from a garden.
But this whole time, it seems, those other plants had been relying on grass for nutrients.
Finding out that grass plays a prominent role in grasslands shouldn’t come as much of a surprise.
But maybe that’s because the word “grassland” is a bit of a misnomer, said McLaren.
“You could call it a meadow,” she said.
The truth is, grasses don’t really take up a lot of space in the Yukon grasslands.
But pound for pound, grasses play a much bigger role than anything else, said McLaren.
McLaren’s laboratory is a one-hectare plot located just beside Kluane Lake.
She divided the plot into one-metre squares. In each square, she picked one plant to be killed.
“I went in with a tiny paintbrush and Roundup, and painted all the individual leaves of the plants,” said McLaren.
“I had to paint them a few times because they wouldn’t die,” she said.
The hardiest plants needed to be dispatched with tweezers.
It was a “knock-out” experiment, said McLaren.
You remove a component, see what happens, and use the observations to gauge its original influence, she explained.
A knock-out experiment on humans, for instance, might start by removing the heart.
When the subject immediately died, the heart’s importance would be duly noted.
Contact Tristin Hopper at