243Sources of Inefficient Use and Conversion
Consider, for example, a large farm that provides both beautiful vistas of open
space for neighbors (or even for travelers on an adjoining road) and habitat for
wildlife in its forests, streams, and rangelands. The owner would be unlikely to
reap all the benefits from providing the vistas because travelers could not always
be excluded from enjoying them, despite the fact that they contribute nothing to
their preservation.
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In the absence of exclusion, the owners receive only a small
proportion of the total benefits. If the owner of the large farm is approached by
someone wanting to buy it for, say, residential development, any self-interested
farmer would not consider the loss of the external benefits of the open space to
wildlife and to travelers when setting a price. As a result, these benefits are likely
to be ignored or undervalued by the landowner, thereby creating a bias in
decisions affecting land use. Specifically, in this case, uses that involve more of
the undervalued activities will lose out to activities that convey more benefits to
the landowner even when, from society’s perspective, that choice is clearly
inefficient.
Consider the implication of these insights in terms of Figure 10.1. In the
presence of externalities, a farmer’s decision whether to preserve agricultural land
that provides a number of external benefits or sell it to a developer is biased toward
development. The owner’s private net benefit curve for agriculture would be lower
than the social net benefit curve. The implication of this bias is that the allocation
of land to agriculture would inefficiently contract and the allocation to residential
development would expand.
One remedy for environmental amenities that are subject to inefficient conver-
sion due to the presence of positive externalities involves direct protection of those
assets by regulation or statute. Take wetlands, for example. Wetlands help protect
water quality in lakes, rivers, streams, and wells by filtering pollutants, nutrients,
and sediments, and they reduce flood damage by storing runoff from heavy rains
and snow melts. They also provide essential habitat for wildlife. Regulations help
to preserve those functions by restricting activities that are likely to damage these
ecological services. For example, draining, dredging, filling, and flooding are
frequently prohibited in shoreland wetlands. As Debate 10.1 points out, however,
the fact that these regulations designed to protect social values may diminish the
value of the landowner’s property has created some controversy about their use.
The Influence of Taxes on Land-Use Conversion
Many governments use taxes on land (and facilities on that land) as a significant
source of revenue. For example, state and federal governments tax estates (includ-
ing the value of land) at the time of death and local governments depend heavily on
property taxes to fund such municipal services as education. In addition to raising
revenue, however, taxes also can affect incentives to convert land from one use to
another, even when such conversions would not be efficient.
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Note that the aesthetic value from open space is a public good. In many, if not most, cases, exclusion
is either impossible or impractical (perhaps simply too expensive) and the benefits from the view are
indivisible.