Much of the land in the Commonwealth is privately owned, predominantly unprotected, predominantly forested land and wetlands- open land that supports native wildlife. This land is...the backbone of the nature of Massachusetts. -- Jennifer Steel (1999) Invest in land! They aren't making any more of it. -- Will Rogers

Forests As Providers of Ecosystem Services

Introduction:

Money doesn't grow on trees, as the old saying goes. If it did, forest conservation would not be controversial. However, there is growing recognition that trees and forests are valuable, not just as sources of timber, but also for the many ecosystem services that they provide. These services include clean water, recreation, carbon storage, and protection of biodiversity. Unfortunately, the value of nature's services are generally not included in the prices we pay for things, and forests are no exception. Therefore, ecosystem services are part of a class of goods called economic externalities. These externalities make natural areas less valuable to individual landowners.

In contrast, the value of services provided by developed land, such as housing and commercial areas, is realized by the landowner, since it is included in the price of the land. The result of this situation is a socially inefficient use of land with which New Englanders are only too familiar: too many condos and shopping malls, but too few forests.

This article considers the problem of realizing nature's value, with a focus on privately owned forests in Massachusetts. Private forests make up 78% of the 3.1 million forested acres in Massachusetts (MFSP 2000). I begin by briefly discussing the significant externalities associated with forests and their consequences for patterns of land development. I then review mechanisms for correcting inefficiencies in land development and evaluate their effectiveness.

It is important to note that this paper uses an economic analysis, so ecosystem services are considered purely from a human point of view. From this perspective, biodiversity has no inherent value. It is only valuable because it provides medicine, knowledge, ecosystem stability, and psychological values that are important to people. The economic approach may be ethically problematic. However, it still moves us in the direction of additional conservation, and it provides strong arguments that appeal to the general public.

Services provided by forestland

Forests provide many goods and services, some of which are reflected in the market. The public benefits provided by private forestland in Massachusetts are summarized below in a report by the Massachusetts Forest Stewardship Program (2000); see Table 1. The most obvious example is timber production. Many landowners do not manage their property for timber. The potential to produce timber locally is, nonetheless, important. Currently, Massachusetts produces about 6% of its wood consumption, but has the potential to produce 41% (MFSP 2000). If energy costs become higher, the transportation savings from local production may become significant.

Table 1. Public benefits from private forestland in Massachusetts (Adapted from MFSP 2000)

Many services provided by forestland are externalities. While recreational benefits to the landowner are part of forestland's market value, recreational benefits to the public are not. Seventeen percent of private forest in Massachusetts is open to public use (DEM 1992) and 23% of state trails are on private land (MFSP 2000). An estimated $1.2 billion was spent on fishing, hunting, and wildlife viewing in Massachusetts in 1996 (Steel 1999). While much of this money was probably spent in public parks, it does suggest that public recreational benefits from private land are significant. Even posted land, where the public is denied access, provides aesthetic benefits to all.

Water quality services provided by forests are another important externality. The case of the Catskills, New York region is a telling example. The State of New York spent $1.3 billion on ecosystem restoration of the Catskills and its forests in order to improve water quality. By doing so, it saved the $8 billion cost of a new water purification plant, as well as $300 million in annual operating costs (Chichilnisky and Heal 1998).

Another key forest service is the reduction of greenhouse effects through carbon storage. This benefit has been capitalized in recent years through carbon offset programs. involving payments for forest protection by companies or countries that are building new utility plants. However, the forests protected under these programs have been in the tropics where most biodiversity hotspots are located; owners of temperate forests have not benefited directly.

In addition to these tangible-use benefits, we are happier just knowing that our forests exist; this is called existence value. As conservation advocates, we can increase the existence value of biodiversity by persuading the public that biodiversity is valuable for its own sake. Existence value is particularly important in New England, where sugar maples and brilliant, autumn foliage are such a strong part of our self-image. Biodiversity derives some of its importance to people from existence value as well. Private forestland is important to biodiversity conservation because it provides some high quality habitat that is unavailable elsewhere. Several of Massachusetts's extremely rare old-growth forest fragments are on private land (R.T. Leverett, pers.comm.). About one-quarter of our state-listed rare species occur in forest habitat (MFSP 2000); many of these are doubtless found in private forests.

To some extent, scenic beauty and clean water are not externalities; they are reflected in the cost of land. In fact, it is the demand for wide open spaces that leads people to move to the suburbs, causing sprawl development. When open space is public land, as is the case in many suburban towns, there is less temptation (and often no legal possibility) to sell it. If open space is privately held, however, the landowner will have great incentive to sell it and let other area landowners suffer the consequences, while he or she pockets the money (Wheaton 1989). This is especially true of absentee landlords.

Not all forests provide the same valuable goods and services. The economic value of a block of forest depends on its size and its context. Larger blocks of forest in less developed areas usually provide better habitat, and require less management for biodiversity (Swallow and Wear 1993). Fragmentation of forest into small lots dissected by roads and surrounded by development degrades habitat quality for many species that require forest interior or mature forest conditions. Some species prefer forest edges or young forests, but because these habitats are plentiful today, they are less valuable on the margin in terms of enhancing biodiversity. Fragmented forests are more likely to be invaded by weedy and exotic species. They recover more slowly and less thoroughly from disturbances than larger forests; in larger tracts, areas untouched by a given disturbance can reseed disturbed areas and buffer them from the impacts of surrounding development.

Larger forests also offer people a better opportunity to get away from it all. On the other hand, forests in urban and suburban areas are scarcer and more convenient to reach. They are, therefore, in greater demand both by people seeking solace and by wildlife looking for a home or stopover. The scarcity of natural areas in cities explains why the Mount Auburn Cemetery in Cambridge, MA is one of the top birdwatching sites in the country during migration season. Rest stops for migrating birds are so few and far between in Greater Boston that the few appropriate natural areas available are used intensively.

Bolund and Hannamar (1999) describe numerous services provided by urban forests. Many of these services, such as noise reduction and the moderation of temperature extremes in the immediate area, are only valuable because of the high population density near these forests. A given area of urban or suburban forest is thus used by more people and wildlife. However, urban and suburban forests tend to provide inferior habitat for threatened species and less significant ecosystem services than larger and less disturbed forests in rural areas.

Why we need to internalize forest values

Every day, Massachusetts converts 44 acres of open space to residential, commercial, or industrial land (Steel 1999). Remote-sensing data indicate that Massachusetts forestland decreased by 2.9% between 1971 and 1985, while developed land increased by 3.2% (Kittredge et al. 1996). A 1998 study by the US Forest Service found that Massachusetts is losing 6,538 acres of forest per year (cited in MFSP 2000). Not all of this development is socially inefficient -- we need more places to live, shop, and work for our increasing population. However, until the values of forests and natural areas can be realized by landowners, we will make many inefficient decisions when faced with a choice between a particular patch of forest or a development.

Inefficient development is a growing problem in Massachusetts. From 1972 to 1998, the Commonwealth's population grew by only 6%, but the amount of developed land increased by 59%, mostly in the form of sprawl development (Steel 1999). Sprawl refers to poorly-planned, heavily automobile-dependent development that spreads rapidly across the landscape. John DeVillars, past administrator of the Environmental Protection Agency's New England office, declared sprawl to be the "number one environmental issue facing New England"and launched a major initiative to combat it (EPA 1999). In addition to ecosystem services, other externalities that make sprawl inefficient include the cost of long commutes and the cost of an extensive infrastructure of roads, schools, and other services.

Inefficient development of open space is particularly serious because its effects take so long to reverse. Some of them are probably irreversible. Most of Massachusetts was once converted to pasture land and has returned to forest over the course of the last 150 years (Foster 1995). The impact of conversion to pasture is still felt in the composition of forest flora and fauna. But the impact of today's development, because it involves pavement and buildings, will be more severe and take much longer to reverse. In addition to outright development of Massachusetts forestland, ownership is becoming increasingly fragmented; the size of the average non-industrial private forest parcel fell from 23.4 ac to 10.6 ac between 1976 to 1989 (Kittredge et al. 1996) and the trend has probably continued. Small forest parcels make it more difficult to manage the forest, whether for timber, biodiversity, or other values. If there were a better market for ecosystem services, there would be greater incentive to maintain large blocks of forest under single ownership where fragmentation would be less likely to become an issue.

Strategies to correct the externality problem fall into two categories: 1) command-and-control approaches, primarily zoning, and 2) market-based strategies, such as purchase of land or development rights and tax incentives. Both approaches have their strengths and weaknesses, but both suffer from the lack of methodology and resources to calculate the conservation value of particular parcels.

Correcting the forest externalities problem: command-and-control approaches

Zoning is the default strategy to control local land use (Thorsnes and Simons 1999), although conservation zoning is a relatively new idea. Towns stipulate in their zoning laws what type of development can occur in which areas. Commercial development is typically limited to certain neighborhoods, while other areas may be off-limits to development in order to protect the town's aquifer. In a typical suburb, most of the town is zoned residential, with minimum requirements for houselot size (one acre, for example). Zoning laws of this sort are exclusionary, since they effectively exclude low-income housing, and they actually encourage sprawl. While they may be intended to maintain neighborhood character and to limit residential development, they make it difficult to cluster development densely in one area in order to leave more room for open space (Steel 1999). Cluster development is allowed under many zoning plans, but requires a special permit (EOCD 1982). Most central and western Massachusetts towns are sparsely populated and, like rural areas across the country, have no zoning laws (Popper 1981). If the growing number of small forest landowners in these areas leads to excessive development for vacation homes, towns may find themselves in need of zoning or other remedies for inefficient growth.

One of the biggest weaknesses of zoning is that it is local, while many development externalities are regional. Recognition of this problem has led to a movement for state land use regulation (Popper 1981). Some states have encouraged the use of zoning plans that limit most growth to special urban growth zones, while designating forest and agricultural zones for special protection. Oregon was the first state to attempt this approach. Oregon's 1973 Land Conservation and Development Act has been imitated by eleven other states (Cooper 1999). Kline and Alig (1999) compare development patterns in Oregon with patterns in neighboring Washington, which had no such law in place until 1990. Their findings suggest that Oregon's program did concentrate open space conversion within urban growth boundaries to a greater extent than occurred in Washington. However, forest use and farm use zones were just as likely to be developed as other areas outside of urban growth boundaries.

Massachusetts has several state land use regulations, notably the Wetlands Protection Act and Rivers Protection Act. These regulations apply to forestland because much of Massachusetts wetlands are forested, as are many of our riverbanks (Payne 1998). The Wetlands Protection Act and Rivers Protection Act require special permits for development on wetlands and riparian corridors. Strong protection is also accorded to land designated as Areas of Critical Environmental Concern (ACEC) under the Massachusetts Environmental Policy Act, which include some forests as well (DEM 1999). These lands are held to be so valuable and so scarce, and their loss so difficult to reverse, that any losses must undergo special scrutiny.

As with other command-and-control approaches, behind-the-scenes negotiation weakens these state regulations. Massachusetts is unusual in that its wetlands regulations are enforced by town conservation commissions. Critics charge that these local bodies are particularly open to influence by developers and that they lack the expertise to enforce environmental regulations (Payne 1998). Nonetheless, the Wetlands Protection Act has slowed conversion of wetlands in Massachusetts; in the mid-80s, more wetlands were replicated in the state than were filled (Payne 1998). Loopholes for powerful interests are common in other state's land-use regulations as well (Popper 1981).

Zoning's greatest strength for most towns is its simplicity; each area of town has a set of requirements which is applied throughout that area. Zoning should also provide greater certainty about the amount of open space conserved than market-based approaches. Correctly worded zoning laws allow residents to set the minimum amount of forest or other open space in town and decide where it will be located. The ability to designate particular areas for conservation is especially important in light of the context dependence of many of the services which forests provide.

Designing conservation zoning to produce the efficient amount and configuration of forest requires large amounts of data about population growth, recreational use and aesthetic value of particular areas, and biodiversity (Thorsnes and Simons 1999). Biodiversity data is now available in most states through the Natural Heritage program, and some states have undertaken the intensive analyses required to produce plans prioritizing particular areas for conservation. One example is the national GAP analysis program with eight state conservation plans already completed and 31 more due to be completed this year (USGS 2000). Information about recreational use, aesthetic, or sentimental value of specific areas is harder to come by. During an intensive open space planning process, Concord, Massachusetts, surveyed its residents to determine which places they considered special (R.T.Forman, pers.comm.), but few towns may wish to spend the time and money required to collect this information.

Zoning is a promising tool. However, most of Massachusetts forestland is located in rural towns with virtually no zoning aside from state regulations. The Sustainable Development bill, currently pending in the state legislature, could help change that by providing funding for town and regional planning (ELM 2000b). The degree to which town zoning laws will serve conservation purposes is limited by what is politically feasible. Restrictive zoning is perceived as unjust. Society gains, but individual landowners lose, since they are not compensated for decreases in land value (Wright 1994).

Market-based approaches to the forest externality problem

There are two main market-based approaches to increasing the amount of forest and other open space conserved: 1) purchase of land or development rights for conservation, 2) tax-based methods to encourage forestry and conservation. Other market-based methods to realize value from open space, such as ecotourism, are not used widely by private landowners in Massachusetts.

Land purchases

Purchasing land for conservation seems to be a straightforward and effective way of achieving the efficient amount of forestland or other open space. An established market exists for land. Conservation players, whether private or public, simply enter this market and buy land to protect it from development. Perhaps for this reason, land purchase has been a very effective approach. The amount of land protected by private groups has been increasing rapidly nationwide. For example, the amount of land protected by US land trusts increased 135% from 1988 to 1998, totaling 4.7 million ac by 1998 (Anon. 1998). In Massachusetts between 1988-1997, 1.48 acres of wildlife habitat were protected for every acre that was developed (Steel 1999). Much of this land was not purchased outright.

Programs to allow purchase of development rights (PDRs) exist in many states, and reduce the cost of protecting land somewhat. PDRs are flexible, since limited development rights or rights on particular sections of a property can be purchased. For example, the Conservation Fund purchased development rights to 110,000 acres of forestland in New York, Vermont, and New Hampshire in 1998. The deal allows public access to the land and ensures that it will not be developed for residential, commercial, or industrial use, while allowing continued logging (ENS 1998). PDRs allow purchases to be tailored to an individual property, an improvement over zoning (Wright 1994). Massachusetts is one of the top three states in the use of PDRs; by 1993, the state had protected 28,000 ac through this method (Wright 1993). PDRs are a way of directly compensating landowners for the benefits they forgo by not developing their land; landowners are paid directly by the government or non-profit purchaser.

Paying for development rights is more practical than paying for uncaptured conservation value, since conservation value is much harder to measure (Polansky et al. 1997). Conservation easements are similar to PDRs and much more widely used, but since easements generally involve the donation of development rights for tax benefits, they will be discussed with other tax-based methods.

One of the main weaknesses of purchasing land or development rights is the free rider problem. Open space is a public good; thus many of its benefits can be enjoyed whether or not one helped pay for them. Therefore, individuals will donate less to conservation organizations than their true willingness to pay. The result is too little forestland and other open space being conserved.

Despite free rider problems, funding for open space has increased in recent years. In 1998, voters approved more than 168 state or local ballot initiatives providing more than $7.5 billion for US preservation efforts (Cooper 1999). In the case of these ballot initiatives, where people vote directly, we have a clearer expression of willingness to pay than most legislation provides.

Another weakness of land purchase, as with zoning, is the requirement for extensive data collection and analysis to determine which land is most efficient to protect. Conservation groups such as The Nature Conservancy conduct lengthy analyses to determine priority areas for protection. Market signals can help clarify the public's priorities. Private conservation groups benefit from market signals since fundraising campaigns are often targeted to particular acquisitions. or at least to acquisition in particular regions. Local ballot initiatives may also be targeted to acquire particular parcels. The recently enacted Massachusetts Community Preservation Act distributes 20% of its funding by giving priority to communities with higher per capita property value and population (ELM 2000a). The result will be a focus on conserving land in areas where development is occuring rapidly.

One attempt to ensure the right amount of land protection despite free rider problems is the linkage of conservation funding to development. Governor Celluci recently committed to protecting 3 ac in Massachusetts for every acre that is developed (Steel 1999). The Community Preservation Act funds open space protection through a small surcharge on real estate transactions (ELM 2000a). These and other linkage formulae are not the result of cost-benefit analysis, but they do represent an attempt to make an independent determination of how much conservation is socially desirable. They also recognize that open space is more valuable the less there is of it.

The conservation-development linkage can be made through taxes on development, or through the use of a Transfer of Development Rights (TDR) program. TDR programs raise money for conservation by selling zoning variances to allow denser development in particular areas. Some TDR programs directly link forgone development in one administratively-defined source zone with denser development in a sink zone. The Massachusetts Rivers Protection Act has proposed such a program using riverfronts as a source zone (DEP 1996). TDRS for an area are often set based on the amount of development that would have been allowed there under normal zoning. The use of these development rights elsewhere is allowed up to some housing density limit set by safety and health concerns.

By 1995, 100 TDR programs had been implemented in the US (Thorsnes and Simons 1999), but most had limited success, probably due to high administrative costs and the programs' complexity, as well as limited demand for dense development (Wright 1994). Two-thirds of the 35,000 ac protected through TDRs by 1994 was in Montgomery County, Maryland, where high demand makes denser developments viable (Wright 1994).

Private conservation tends to be more politically acceptable than government land purchases. However, private fundraising difficulties have led some groups to partnerships with the government that have eroded their political advantage. Private groups find it especially difficult to raise funds for continuing management of land, as compared to its acquisition. For this reason, groups such as The Nature Conservancy routinely purchase land and resell it to the government, often at a significantly higher price than they paid for it (Edwards 1995). Government agencies gain from the flexibility and effectiveness of private groups in acquiring land, and private groups are freed from the need to raise money for management. However, many people mistrust government ownership of private land and view such arrangements as deceptive (Holt and Budd 1996). Furthermore, even The Nature Conservancy admits that the government does not always do an adequate job of managing its properties (Edwards 1995). It appears that free riding is even more of a problem when it comes to paying for management of conservation land than for acquisition. From a practical point of view, it is unlikely that enough money will be allocated to directly purchase as much forestland as should be protected.

Tax incentives for conservation

To help individuals realize the conservation values of their land, tax-based methods are widely used. Generally, land is taxed based on the value of its most lucrative use. The value of a forest lot for tax purposes might be based on the price a developer of luxury housing would pay for it. This taxation system imposes an additional cost to landowners of conserving their forests; it was found to be a significant barrier to conservation by the Northern Forests Land Council (MFSP 2000). In most states, this property tax burden can be substantially reduced through conservation easements. Nationally, the most important tax tool for conservation is the easement, although easements are not used as widely in New England. In the Southern US, 41% of protected land is in easements, while in the Rocky Mountain zone, the figure is 84% (Wright 1994).

Conservation easements involve the donation of development rights to a government or private conservation group. The value of the donation can be deducted from income and estate taxes, as well as reducing the capital gains tax on the sale of land. Massachusetts Chapter 61 program for forestry, agricultural, and recreation land stipulates that such land is no longer taxed at its highest potential use, but only at the value of its present use (CCH 1987). Chapter 61 land does not have to carry an easement. Enrollment requirements vary for the three categories of land, but all of them carry penalties for early withdrawal from the program and give the municipality the option to purchase the land if it is sold or converted to another use (CCH 1987). In 1992, about 224,000 acres were enrolled in Chapter 61, representing less than 8% of the private non-industrial forest in Massachusetts (DEM 1992).

Tax breaks for conservation land help to correct forest externalities, but little effort has been made to link the size of the tax break to the conservation value of the land. To some extent, more valuable conservation land receives larger tax breaks because it tends to be either nearer to population centers or larger. Proximity to population centers and size of properties are both linked to conservation value. They are also linked to property value on the market, so tax breaks for such properties will be larger. However, tax breaks won't necessarily be equivalent to conservation value. One effort to link tax breaks to conservation value is the federal requirement that conservation easements must provide significant public benefit in order to qualify for a tax break. Recreational, ecological, open space (scenic or conservation), or historic value all help a property to qualify (Wright 1994). There are proposals to drop this requirement (Cooper 1999), which suggests that a significant number of properties do not qualify currently.

In Massachusetts, Chapter 61 regulations require a parcel to be of a minimum size and in appropriate condition to qualify for a tax break (CCH 1987). These requirements eliminate certain properties from eligibility, but they do nothing to make the size of the tax break equivalent to conservation value. Conservation value appears to be too difficult to measure at present for inclusion in the tax laws (Salzman 1997). However, a ranking system has been proposed for Massachusetts that would provide increased conservation incentives for land in state or federally designated priority areas, such as Natural Heritage critical habitat polygons, ACECs, and ground water supply areas (MFSP 2000).

One of the weaknesses of tax-based approaches is the uncertainty about how much land will be conserved under these programs. Unless the conservation value of individual parcels were known and tied to the size of tax breaks, we would not expect an efficient outcome. Furthermore, participation in the programs is voluntary and may be limited, as in the case of the Chapter 61 forestry program (MFSP 2000). While costs are usually more predictable under tax-based approaches than under regulatory approaches, the voluntary nature of these programs make them less predictable. Tax breaks may not provide much incentive to low-income landowners with low tax burdens. However, reductions in property taxes and estate taxes may still be attractive to individuals who are land-rich and cash-poor. Tax breaks can be adjusted in size if they are resulting in an inefficient amount of conservation. At any rate, these programs do push us in the direction of efficiency.

Conclusion

Land conservation is on the rise in Massachusetts, as it is throughout the US (Cooper 1999). However, development is also proceeding at an alarming rate. While zoning can play a role in discouraging sprawl, market-based strategies -- especially land purchases and tax breaks for conservation easements -- appear to be most effective at preserving land from development. Conservation easements seem especially promising for two reasons. First, easements do not suffer from the free rider problem. Second, management of land with easements is generally done by the landowner, with monitoring by the conservation group to ensure compliance with restrictions on at least an annual basis (Wright 1993). Annual monitoring is adequate because the impacts of improper management (e.g., on an indicator species) are usually apparent. This reduces the need to raise funds for management.

The efficiency effects of easements would be greatly enhanced if tax benefits were tied to conservation value in some way. Biodiversity data and regional conservation plans are becoming more readily available. The MFSP's proposed model is a practical way to establish a simple ranking system for a parcel's conservation value. Increased tax benefits could be given for parcels with higher ranking. Such a system would create an incentive for the increasing number of small landowners in Massachusetts and elsewhere to band together in order to enhance the conservation value of each of their parcels. At the very least, such a measure would increase public awareness of ecosystem services, leading to the realization that, in some sense, money does grow on trees.

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