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Government Policy Ignores
Genetic Realities
© 1997, 1998 Streamline
Publications
Preserve Native Genetic
Biodiversity could be a slogan printed on Forest Service employees'
T-shirts and fire truck bumper stickers. Not very catchy, as slogans go, but one
that most folks would agree with. In a U.S. Forest Service policy dated
June 30, 1994 this goal was defined. The policy addresses revegetation of
disturbed land using native seeds and plants for fire rehabilitation, riparian
restoration, forage enhancement and other vegetation projects. 
"I'm sorry I bonked you, Algernon, but next time you want to explore my genetic diversity, ask first."
The essence of the policy is that when
such soil disturbances are to be replanted the seeds should "...originate
from genetically local sources of native plants." A knowledgeable plant
resource specialist is to develop a prescriptive plan using suitable plant
material from the local environment. The plan entails collection or purchase
of seeds, cuttings and whole plants that are healthy and free of pests. While
some such qualifying seeds may be available on the local market, it is unlikely
that many exist that fit the narrow prescription of "genetically local
native species." Except for some flexibility allowed for emergency
situations, this policy strongly encourages collection of ecotype species from
the local environment—a costly and time-consuming approach to revegetation.
Less Diversity Beyond the cost and time involved
nature's variables are likely to limit the effectiveness of such a plan. The
makeup of the plant life in each microclimate is molded by many factors that
contribute to that environment: moisture, evapotranspiration rates, temperature
and frost cycles, light, weather exposure, soil type and pH. Even the pests that
challenge the plants have an effect on genetics. Certain plants will mature and seed
over a short period, others will take longer. The period of seed setting will
affect harvest time for the seed collectors. Collecting seed during only a
portion of this time has the effect of further limiting the genetic diversity.
Genetics of the plants can change over
a relatively short period to take advantage of properties that allow survival in
that area. Ecotypes are created, species whose dominant genetic
characteristics are narrowed to those necessary for the plant to thrive in a
particular small locale. The species' genetic properties are "trimmed"
through this process of natural selection resulting in a plant that may not be
well adapted to other sites within the same climate zone. The soil properties found just a few
hundred yards away could very well be unable to support such a narrowly adapted
plant simply because of its lack of genetic diversity. On the other hand,
commercially-available grasses and forbs possess, of necessity, high genetic
diversity—properties that allow establishment and propagation in a wide
range of environments. In addition, these commercial seeds have been tested, and
have properties that are well-known and predictable. What's more, they are
available immediately, an important factor when a disturbed area faces erosion
from coming winter weather. This is the time for action using proven methods and
materials, not for a plant resource specialist to begin planning seed
collections from "local genetic sources."
A Reasonable Policy
This is not to say that use of local
plant sources is wrong, only that under such guidelines as these, erosion may
become an even greater problem. The cost of this program is high and the outcome
uncertain at best, with unintended consequences a distinct possibility.
Unlike the Forest Service's experience
with trees, that take decades or centuries to show evidence of genetic mistakes,
faster maturing grasses and forbs can select out traits in as little as a single
season. The goal of the Forest Service is commendable, but the genetic realities
of revegetation call for a policy more reasonable, reasoned and cost effective.
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