April 21, 2004
Review of Wildland Vegetation Management
1. How do we manage vegetation?
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There are easy and there are difficult answers to this question. The easy answers deal
with the methods used for removing and introducing vegetation components. For
example, there may be situations where unwanted species should be removed. In the
course of this course we discussed removal by fire, herbicide, uprooting and logging.
Of these, fire may be the most disruptive method, often requiring reseeding the
desired vegetation components after the fire. Uprooting may be the most direct and
effective method, but since it is very labor- intensive this can only be done on a small
scale (e.g. one side of a mountain in Saguaro National Park). Wanted vegetation, if it
is present in insufficient amounts, can be re-introduced by seeding or planting, often
requiring adequate site preparation to be successful. Sometimes, just removing the
competitors (e.g. invaders) may be enough to increase the density of desired plant
species.
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The question of how to protect and maintain desired vegetation is already a more
difficult question. Over-harvesting the vegetation, should certainly be avoided. Many
vegetation types also require a specific disturbance regime (e.g. by fire or flooding) to
remain in a desired state. Because plant performance depends so much on soil quality,
it is always important to protect the soil. This involves minimizing erosion,
maintaining soil fertility, and protecting soil food chains. Oftentimes, vegetation will
be threatened from the outside, however, rather than through problems arising on the
inside of the management unit. Examples are the influx of diseases or invaders, and
poor air and water quality. At this point at last, as vegetation managers we have to
acknowledge that we need to look beyond vegetation itself, and beyond the borders of
a management unit, to effectively manage vegetation.
2. What drives vegetation changes?

It seems that wildland vegetation has changed and is still changing everywhere. It has
become a big effort just to maintain it in its current state. This tendency is not
difficult to understand, if we consider where we are in human history. About 150
years ago, humans embarked on a period of explosive population growth. European
colonization of the world reached its maximum, just around the time that settlers
arrived in the Western US with their mid-eastern cattle breed and old world weeds.
An ever-increasing number of humans require ever more food and shelter. Places that
served as habitat for many species are either being transformed to agriculture or
recklessly over-exploited, causing record-setting extinction rates. Increasing demands
for energy pump CO2, other greenhouse gases, and nitrogen compounds into the
atmosphere, which heat up the biosphere, change the hydrological cycle, and
ultimately cause vegetation changes on a global scale.
April 21, 2004
3. Why is degraded vegetation so difficult to rehabilitate?
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Once vegetation is transformed through the work of multiple stressors, such as
overuse, erosion, invasion, it is difficult to bring back into its original state. Just
removing the stressors usually does not do the trick. The reason is that not just the
vegetation, but the whole ecosystem changed and now resists return to an earlier
state. The Alternative Stable State Model acknowledges that once an ecosystem is
transformed into a degraded state, it may be difficult to bring it back, because too
many ecosystem processes have changed. Feedback mechanisms that once helped the
pristine ecosystem to bounce back after disturbance (i.e. stabilized it), have been
interrupted and replaced by new feedback mechanisms that resist return the prostine
state. For example, where once frequent fire in dense grasslands stayed off the spread
of woody shrubs, now a patchy grassland offers better opportunities for shrub
establishment, while fire does not burn hot enough anymore to kill shrub seedlings.
To make things worse, established shrubs trap plant litter and grow small islands of
soil fertility under their canopies, which takes nutrients away from the grasses.
Grazing and drought probably triggered this transformation, but even in the absence
of grazing and drought, the grasslands cannot return to its earlier state.
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The point is, to manage vegetation effectively, we must manage whole ecosystems.
Trouble is, ecosystems have no boundaries and effects of ecosystem changes can be
felt a long distance away, just as changes caused a long distance away can affect local
ecosystems. Ultimately this means that wildland management must be performed at a
scale that involve entire societies. Even tough problems may be local (declining
fisheries in the Gulf of Mexico), solutions cannot be found at a local level. Sometimes
it requires an entire nation changing its goals and priorities.
4. What are society’s goals for its biological resources?

There could be many, such as building equity, promoting fairness, maintaining
natural beauty, maximizing profit. The one globally most recognized societal goal is
sustainability of natural resources. This goal emphasizes that society must protect
resources not just for the immediate future, but for all future generations. Since we
can’t know for sure what future generations might want with natural resources, and
often we are ignorant about the importance of certain ecosystem components, we
must protect even those resources that do not seem very useful at all, including for
example, each and everyone of a gazillion species of bugs.

In modern societies, there are many ways to make a living. Therefore, people usually
have conflicts of interest. One of the most difficult responsibilities of land managers
is to resolve such conflicts. Top-down management used to be the standard for federal
agencies, based on the conviction that natural resource experts know best what is the
optimal management practice. Local stakeholders tend not to like this, because they
feel excluded from the decision-making process.
April 21, 2004
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In more and more natural resource conflicts, a new management philosophy is put
into practice, one that builds on the experience of many stakeholders and attempts to
make management decisions by consensus. Also, resource managers and stakeholders
are learning that no management decision should be trusted, but that the effectiveness
of management practice must be continually checked and adjusted. There is hope that
this open-ended management philosophy will allow us to respond to new challenges
in time, in a rapidly changing world.
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With livelihoods at stake, management decisions often revolve around money. A
society must try to balance the value of protecting ecosystem function and services,
with the costs to society. However, there’s a problem. How do you measure the value
of natural beauty, recreational options, clean water? Sometimes, ecosystem goods
services either have a market value or are closely linked to items that have a market
value, and so one can estimate its monetary equivalent. But this does not reflect the
full value of an ecosystem, because intangibles such as beauty, or the good feeling
you get, just knowing that an ecosystem exists, should also have a value. Sometimes,
natural resource economists use questionnaires to learn about people’s attitudes
towards natural resources.
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In summary, the practice of wildland vegetation management goes far beyond the
manipulation of plant species in some small place in the world. Even though the
biological problems can be difficult enough, the political problems associated with
land management may be even greater. Of course, land managers do not have the
power, nor the means to work on all issues, but it is important to know what all the
issues are, so that management options can be evaluated within the bigger contexts of
climate change, land use changes, and society’s goals.