WHO INTRODUCED THE HIMALAYAN BLACKBERRY?
By Jennifer Anderson
Lake Oswego Review
Sept 11 2008
OR
Dealing with an invader like the Himalayan blackberry can be daunting
but not stopping it means the aggressive pest will gain a tighter
chokehold on native plants.
If you haven’t noticed the rubus armeniacus invading your backyard,
consider yourself lucky.
As many Oregonians well know, the Himalayan blackberry – one of three
species that make this state the blackberry capital of the world –
is considered the Godzilla of invasive species.
Sure, the juicy berry makes for great pies and jams. But according
to the Oregon Department of Agriculture, the Himalaya is "the most
widespread and economically disruptive of all the noxious weeds in
western Oregon. It aggressively displaces native plant species,
dominates most riparian habitats, and has a significant economic
impact on right-of-way maintenance, agriculture, park maintenance
and forest production."
So just who was responsible for unleashing this aggressor, and what
were they thinking?
Blame botanist Botanist Luther Burbank, regarded as the father of
modern plant breeding, brought a cultivar of the species to the
U.S. in 1885 under the name "Himalaya Giant," because he thought it
would make a good backyard crop.
Burbank had obtained the seeds from an exchange with someone in
India. But as it happens, the plant originated in Armenia and then
was brought to Germany.
In his field notes, "Luther Burbank; His Methods and Discoveries
and their Practical Application (Volume VI)," the botanist sang the
praises of the prolific and vigorous berry and described how he grew
it in his home garden in Santa Rosa, Calif.
After the seed started spreading along the West Coast by birds and
other animals, "its popularity was so great that for several years
the plants could not be multiplied fast enough to meet the demand,"
he wrote. "It is a plant of extraordinary vigor."
He had no idea how right he was. Today, it’s up to Jennifer Goodridge,
invasive plant coordinator for the Portland Bureau of Environmental
Services, to make sure the blackberry doesn’t stomp out all other
forms of life as we know it.
"One of the biggest problems with invasives is their ability to form
a monoculture and preclude the establishment of other species,"
she said. "They change the ecosystem process. Next to a stream,
they change the shape, erosion, wildlife habitat. That’s what makes
something invasive and not just lawn grass."
Policy targets plant pests Since the city held a summit on invasive
plants three years ago, Goodridge has been using the feedback to craft
an invasive plant policy for the city. She’ll bring a draft version,
with a 10-year goal, to a follow-up summit in November.
It’s likely the policy will highlight the work that’s being done with
local nonprofit, neighborhood and conservation groups to stem the
tide of the blackberry and its sinister cohorts, holly and ivy. The
policy also will look to continue the three major control initiatives
under way.
They include a Portland Parks & Recreation effort to pare down the
invasive pest in areas where it’s not yet overgrown; a BES program
to restore native vegetation to areas that are heavily infested; and
a partnership with the fire bureau to clear the canopies in forested
areas, such as the Willamette Bluff, Oaks Bottom and Forest Park.
When a fire breaks out in these areas, blackberries and other invasive
plants act as "ladder fuels" that can easily spread flames into
overhanging canopies and threaten nearby homes, Goodridge said.
Yet no matter what strategy the city employs to squelch the mighty
blackberry’s growth, the species probably is around to stay for a
while – basically because its fruit is just too darn tasty, says Mark
Wilson, a parks ecologist.
"It’s probably our No. 1 invasive species in our natural areas in
the city of Portland," he said. "It’s incredibly difficult to get
rid of. There’s no biological control of it and probably won’t be
for a while because the rubus genus is a cash crop. There are lots
of rubuses – Marions, raspberries – and if we develop a biocontrol
agent such as a bug or disease, it will affect those commercial crops."