Dear HCN,
Robert Nold’s dismissal
of the threat posed by non-native species is a classic case of
denial (HCN, 8/3/98). By his own admission, he has “grown about
2,000 species of plants … and few have shown any “irreversible”
tendencies to invade native habitats.”
Observation has shown me that “a few” is all it
takes.
Since moving to central Oregon, I’ve seen
cheatgrass, medusahead, mustard, knapweed, star thistle, Russian
thistle, kochia and teasels (to name just a few non-native weeds)
invade an ever-expanding acreage of range land that formerly
consisted mainly of native bunchgrasses and sagebrush. Although
irrigated areas may contain a greater number of these weeds than
naturally dry areas, most thrive anywhere the ground has been
disturbed by man or livestock.
In the nearby
Ochoco National Forest, other noxious weeds doing fine without any
“supplemental irrigation” are hoary cress, tansy ragwort, Dalmatian
toadflax, Scotch broom, puncture vine, Saint-John’s-wort, Russian
and spotted knapweed, bull, Scotch and Canada thistles, Dyer’s woad
and burdock.
Invaders displacing native flora
elsewhere in the United States include the Eurasian tamarisk, leafy
spurge, kudzu vine, Australian melaleuca, and Brazilian pepper. The
U.S. Department of Agriculture estimates that the United States is
now home to over 4,000 non-native plants and 2,300 alien animal
species, costing the country $122 billion a
year.
This reduces biodiversity and causes
extinctions worldwide. Here in Oregon, the latest invader is the
Atlantic green crab, which, if not brought under control, will
decimate the Northwest’s oyster beds and destroy a $40 million
annual industry. I just hope that Nold’s Pollyanna nonsense hasn’t
won him any believers among what I trust are the more well-informed
readers of this paper.
Helen
Jones
Prineville,
Oregon
This article appeared in the print edition of the magazine with the headline Exotics not a threat? Don’t believe it.
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