Farms may appear idyllic, but are they ideal from [...]]]> According to a 2001 agricultural economic report, “urban expansion claimed more than 1 million acres per year between 1960 and 1990″ in the United States, and that expansion follows one of two two routes: 1. expansion of urban areas or 2. large-lot development (greater than 1 acre per house). (Heimlich 2001)

Farms may appear idyllic, but are they ideal from an environmental perspective?

Land trusts throughout the United States have reacted to this trend of the loss of agricultural land to urban developers by working to protect farms and ranches (and some mixed-use tree farm operations) by creating easements for them as “working landscapes.” For purposes of discussion, forests have been teased out from the farm and ranching portion of ‘working landscapes’ since even, “Tree plantations are more biodiverse [than an annual crop], even though such plantations may be less complex than a ‘wild’ stand.” (Dekker-Robertson 1998)

Let’s not fool ourselves, no perfect solution exists (whether it be market-driven, government mandated or mixed enterprise) to our environmental needs for open space. On the contrary, compromises must be found. No right and perfect answer exists; only “good enough” exists.

At first glance, the creation of working landscapes appear environmentally correct. One would have thought allowing ranching and farming families to stay in business and ostensibly ward off urban encroachment would have been a good thing. After all, they are our neighbors and as such they hold a special place in our hearts (mine included). Now, I’m not as certain, at least from an ecologic or economic vantage point. Working landscapes now appear to be a form of environmental correctness.

What impresses me about the “working landscapes” solution is that it is neither government mandated nor is it funded by tax dollars (except to the degree that land trusts are tax-exempt as 501.C.3s). Farmers and/or ranchers who agree to a land trust’s requirements to maintain a working landscape bolster the land’s economic production.

What concerns me regarding “working landscapes” is that agriculture is arguably the most ecologically disruptive activities we humans engage in. There is no question that we are better off due to the invention of agriculture. Yet, we have become more efficient at growing food and fiber which means fewer acres are needed to grow food per capita. The upshot then is, saving a ranch or farm may not be our wisest course of action and freeing the land up for other uses (even urbanization) may actually be beneficial. As a result, working landscapes may not be better for our environment than urban development.

Proponents give an array of arguments for preserving, protecting, and maintaining working landscapes. (Arizona Land and Water Trust n.d.) (National Park Service 2008) (Morse 2010) These include preventing:

1. Loss of regional identity, distinctiveness, and character and its corollary loss of context for stories linking people to the land and an estrangement from the landscapes sustaining us

2. Unraveling of traditional social/economic relationships to the land and loss of special products of place

3. Loss of models in sustainable landscapes and living cultures

4. Fragmented landscapes

5. Loss of biological diversity

6. Food insecurity

7. Climate change

Below are my responses to each of these arguments and why I think they are overblown.

1. Loss of regional identity, etc.

Not just in the U.S. but also worldwide, the stories and the character of the land and those who work it are being lost. This comes as a byproduct of progress, the homogenization of time and place. Since humans began trading with one another and thus specializing in the products we did best, we have lost the ability and knowledge of how things are made. We have lost the ability to fashion projectile points from rock. The Stone Age did not come to an end from lack of stones; they were replaced by other and better materials and made into new products. Maintaining working landscapes to prevent loss of regional identity, distinctiveness, and character is, at best, a rear-guard effort that will devolve into a situation where tourists will stop to interact with docents who will explain how it used to be done. In other words, I believe that the working landscapes will become anachronisms

2. The unraveling of traditional social/economic relationships to the land and loss of special products of place.

The second reason to prevent loss of social/economic relationships for those “special products of the place” aligns itself closely to the first argument of preventing loss of place. Prevention again is a rear-guard action. As has been happening for the last ten thousand years because of trade and specialization, places are becoming more similar and less distinctive. Farmers, displaced from the ‘Euxine Lake’ when the sea level rose and broke through the Hellespont, brought their seeds with them, so Northern Europe lost its special products of place when the farmers planted the newer emmer and einkorn wheat grains. (Ridley 2010) The items we treasure as distinctive to place may not be as permanent as we would prefer to believe. Just because something is what we happen to have in our memory does not mean that it has always been that way.

As for those special products of place, we no longer manufacture Acheulian hand axes. After all Acheulian hand axes used to be quite special; the most important item for people, no matter the place, for one million years. (Ridley 2010) Yet, we no longer fret that no one uses them anymore. Once an item or process has been replaced, we have to move on–I do not see how farming and ranching is any different.

3. Loss of models in sustainable landscapes and living cultures.

The term “sustainable” is the term du jour and means many things to many people. Yet the loss of this “sustainable landscape” stems from its inability to provide an income sufficient to ward off other encroaching income streams: farming/ranching became unsustainable from an economic point of view. That is the land succumbs to its “highest, best use.” Rather than being something to mourn, the trade from one use to another may be a natural outcome toward greater sustainability. By trading land for money, the rancher or farmer may prove to be better off than before. “Interdependence of the world through trade is the very thing that makes modern life as sustainable as it is,” says Matt Ridley, “suppose your local wheat farmer tells you that last year’s rains means he will have to cut his flour delivery in half. You will have to go hungry.” Today, you benefit from a global marketplace; “in which somebody somewhere has something to sell you so there are rarely shortages, only modest price fluctuations.” (Ridley 2010)

“Economists have long recognized the welfare gains from specialization and trade,” wrote Steve Sexton on the Freakonomics website. “The case for specialization is perhaps nowhere stronger than in agriculture, where the costs of production depend on natural resource endowments, such as temperature, rainfall, and sunlight, as well as soil quality, pest infestations, and land costs. Different crops demand different conditions and vary in their resilience to shocks. So California, with mild winters, warm summers, and fertile soils produces all U.S.-grown almonds and 80 percent of U.S. strawberries and grapes. Idaho, on the other hand, produces 30 percent of the country’s russet potatoes because warm days and cool nights during the season, combined with rich volcanic soils, make for ideal growing conditions.” (Sexton 2011)

4. Fragmented landscapes.

This argument makes little sense. Farming and ranching patch quilts our landscape. Farming is a disruption of a natural landscape (often through deforestation) to grow food or fiber. Today, much of our fiber, though not our food, can be made from petroleum products with a much smaller footprint than agriculture. Urban areas need much less space compared to agriculture. The urban areas in the United States occupy about 3 percent of the U.S. whereas agricultural land occupies nearly 50 percent. (Frey 1995) It would seem more advantageous to have land revert to its natural state through use of greenbelts around urban areas.

5. Loss of biological diversity.

This argument aligns with the previous: the loss of biological diversity already happened when the area changed to agriculture. Agriculture fragments and disrupts natural habitats. In addition, predators to the crop, flock or herd (which are often displaced by the agriculture pursuit) are subdued through mechanical and chemical means. Maintaining working landscapes means ensuring the loss of biological diversity, not preventing it.

6. Food insecurity.

The desire of the land trusts is to protect small family farms and ranches because they are close by and therefore can provide food and fiber. Steve Sexton, writing on the Freakonomics website says, “[I]mplicit in the argument that local farming is better for the environment than industrial agriculture is an assumption that a ‘relocalized’ food system can be just as efficient as today’s modern farming. That assumption is simply wrong. Today’s high crop yields and low costs reflect gains from specialization and trade, as well as scale and scope economies that would be forsaken under the food system that locavores endorse.” (Sexton 2011)

And, as noted by Jesse Ausubel, this argument does not stand up: “For centuries, farmers expanded cropland faster than population grew, and thus cropland per person rose. When we needed more food, we ploughed more land, and fears about running out of arable land grew. But fifty years ago, farmers stopped plowing up more nature per capita. Meanwhile, growth in calories in the world’s food supply has continued to outpace population, especially in poor countries. Per hectare, farmers lifted world grain yields about 2 percent annually since 1960. Two percent sounds small but compounds to large effects: it doubles in 35 years and quadruples in 70.

“Vast frontiers for even more agricultural improvement remain open. On the same area, the average world farmer grows only about 20% of the corn or beans of the top Iowa farmer, and the average Iowa farmer lags more than 30 years behind the yields of his most productive neighbor. Top producers now grow more than 20 tons of corn per hectare compared with a world average for all crops of about 2. From one hectare, an American farmer in 1900 could provide calories or protein for a year for 3 people. In 1999 the top farmers can feed 80 people for a year from the same area. So farmland again abounds, disappointing sellers who get cheap prices per hectare almost everywhere.” (Ausubel 1999)

Lastly, the United States Department of Agriculture is not sounding the full alarm, yet: “[Urban expansion] is not seen as a threat to most farming, although it may reduce production of some high-value or specialty crops. [emphasis added] The consequences of continued large–lot development may be less sanguine, since it consumes much more land per unit of housing than the typical suburb.” (Heimlich 2001)

7. Climate change.

Preventing climate change (by proclaiming his pet project prevents it) seems to be the last bastion of the scoundrel. Whereas it used to be that everything caused pollution, it now gets weighed by its “carbon footprint.” Sexton says this about the advisability of small farms for lowering carbon emissions, “The Harvard economist Ed Glaeser estimates that carbon emissions from transportation don’t decline in a locavore future because local farms reduce population density as potential homes are displaced by community gardens. Less-dense cities mean more driving and more carbon emissions. Transportation only accounts for 11 percent of the carbon embodied in food anyway, according to a 2008 study by researchers at Carnegie Mellon; 83 percent comes from production.”

Summary

So, to a Physiocrat or Romantic, preservation of so-called working landscapes may make sense. They preserve viewscapes, allow a traditional way of life to continue (ranching and farming), help our agricultural neighbors survive in these difficult economic times, and help maintain a region’s distinctiveness and character.

However, from an ecological and economic perspective maintaining agricultural holdings makes very little sense. “The worst thing for the environment is farming,” says Dr. Pamela Ronald, “It doesn’t matter if it is organic [or conventional]…You have to go in and destroy everything.” (Voosen, 2010) We currently use nearly 40% of Earth’s ice-free land for our food and fiber needs. According to one source, that’s an “area 60 times larger than the combined area of all the world’s cities and suburbs.” (Wilcox 2011)

If the area figure cited is even close to true (and it appears that it’s close to the mark), then it is more beneficial to allow farms and ranches to revert to wildland (and urbanized area), especially if they are not economically viable.

Sources

• Arizona Land and Water Trust. Working Landscapes. http://www.alwt.org/whatwedo/workinglandscapes.shtml (accessed November 2011).
• Ausubel, Jesse. “Resources are Elastic.” Earth Matters pp. 46-47, Winter 1999/2000.
• Dekker-Robertson, Donna, Libby, William J. “American Forest Policy: Some Global Ethical Tradeoffs.” BioScience 48, no. 6 (June 1998).
• Frey, H. Thomas. “Trends in Land Use in the United States.” In The State of Humanity, by Julian Simon, 435-440. Cambridge, Mass: Blackwell, 1995.
• Grewell, J. Bishop. “Farming for the Future: Agriculture’s Next Generation.” PERC Policy Series, September 2002: 32.
• Heimlich, Ralph E. and William D. Anderson. Development at the Urban Fringe and Beyond: Impacts on Agriculture and Rural Land. Agricultural Economic Report No. 803, Economic Research Service, U.S. Department of Agriculture, Economic Research Service, U.S. Department of Agriculture, 2001.
• Morse, C. E., Kujawa, R. Strategies for Promoting Working Landscapes in North America and Europe. Vermont Council on Rural Development, Vermont Council on Rural Development, 2010.
• National Park Service. “Executive Summary, The Future of Working Cultural Landscapes: Parks, Partners, and Local Products October 21-22, 2008.” The Future of Working Cultural Landscapes: Parks, Partners, and Local Products October 21-22, 2008. National Park Service, 2008.
• Ridley, Matt. The Rational Optimist: How Prosperity Evolves. New York, New York: HarperCollins, 2010.
• Sexton, Steve. The Inefficiency of Local Food. 11 14, 2011. http://www.freakonomics.com/2011/11/14/the-inefficiency-of-local-food/ (accessed 11 14, 2011).
• Voosen, Paul. Can We Feed the World Without Damaging It? January 4 2010. http://www.nytimes.com/gwire/2010/01/04/04greenwire-can-we-feed-the-world-without-damaging-it-99381.html?pagewanted=all (accessed November 28 2011)
• Wilcox, Christie. Science Sushi Mythbusting 101: Organic Farming > Conventional Agriculture. 07 18, 2011. http://blogs.scientificamerican.com/science-sushi/2011/07/18/mythbusting-101-organic-farming-conventional-agriculture/ (accessed 11 27, 2011).

The Dendrochronolgists were interested in the tree-ring patterns. Trees grow fast or slow in response to many factors and these seasonal factors (light, water, nutrients) created ring signatures or patterns. Certain years might have been favorable for growth with plentiful water, light and nutrients (each favorable year would be marked [...]]]> I used to work on Mountain Home State Forest in the southern Sierra. MHSF has about 3000 specimen-sized sequoia within its boundaries. Dendrochronolgists often visited to see the stumps from logging in the mid to late 1800s. These were often over 2000 years old when they had been cut.

The Dendrochronolgists were interested in the tree-ring patterns. Trees grow fast or slow in response to many factors and these seasonal factors (light, water, nutrients) created ring signatures or patterns. Certain years might have been favorable for growth with plentiful water, light and nutrients (each favorable year would be marked a large, wide ring) and certain years might have had poor conditions for growth–drought, late spring conditions, early winter–marked by thin (in some cases–microscopic) rings. In general, the wider the ring the more favorable the growing season, the narrower the ring the poor the growing conditions. These ring patterns can be distinctive and can be used to date archeological sites (where wood is present).

Oxford’s Tree-ring Laboratory put it this way:

The way dendrochronology works is relatively simple. As a tree grows, it puts on a new growth or tree-ring every year, just under the bark. Trees grow, and put on tree-rings, at different rates according to the weather in any given year: a wider ring in a favourable year and a narrower ring in an unfavourable year. Thus, over a long period of time (say 60 years or more) there will be a corresponding sequence of tree-rings giving a pattern of wider and narrower rings which reflect droughts, cold summers, etc. In effect, the span of years during which a tree has lived will be represented by a unique fingerprint, which can be detected in other geographically-similar tree-ring chronologies.

Using tree rings as a proxy for temperature however is fraught with caveats and pitfalls.

Mike D.‘s of the Western Institute for Study of the Environment comment (on William M. Briggs’ blog) about using tree ring data as proxies for temperature is an excellent explanation of the problems of using tree ring growth for temperature. He starts with how tree rings are laid down:

Diameter growth on any tree is theoretically a sigmoid growth function. No tree puts on constant radial growth year after year. Trees grow by adding a layer of new wood at the cambium, under the bark. Each year a larger surface area is added. If growth is constant, the rings get narrower. But growth is never constant. There is significant deviation from ideal (model) sigmoid diameter growth in individual trees regardless of the weather. Even when sigmoid growth models are used, the natural variation adds statistical error.

Two sigmoid curves. The taller is the period annual increment for cubic feet; the lower smoother S curve is for mean annual increment of cubic feet.

So as the diameter expands, the amount of material put on would need to be more if the ring’s width was to stay the same as the previous season. Think of a clay disk that you add the same amount of clay to in successive rings. The volume of clay would be the same but the thickness of each new ring would decrease. The ring growth is S-shaped (sigmoid) because initially the tree has little foliage for photosynthesis and often puts its initial years into root development for survival. Then once roots are deep enough the tree puts its growth into height and width.

He then points out that tree-to-tree competition for light, water, and nutrients also affects the ring growth:

Dense stands exhibit narrow rings on individual trees, sparser stands may have wider ring growth, yet both stands may have equivalent gross growth. That’s why only open-grown trees are supposed to be selected for ring studies. But nobody knows what the tree density surrounding an individual tree was 100, 200, 500 years ago. Competitors could have arisen and died without leaving evidence of their presence so long ago. More error.

Besides competition, disease and injury can affect growth.

Trees can sustain injuries that affect growth, such as top and branch damage, that are difficult to detect 200 years later, especially a few feet off the ground where the rings are sampled. There are very few pristine, undamaged trees. I know, having searched for such across broad acreages. Open grown trees at high elevations are always damaged. A heavy winter snow can snap off branches and the tree will exhibit reduced diameter growth for a few years, even if growing season conditions are ideal.

This makes using tree ring data as stand-ins for temperature problematic.

Ring width has all but been abandoned as a temperature proxy. Instead, the latest technique is sampling rings for O18 ratios, under the assumption that O18 varies with temperature. Regardless of the ring width, the O18 ratio is supposed to have recorded growing season temperature. But that theory is fuzzy and mushy, and O18 ratios in living trees correlate very poorly with known growing season temperatures. In other words, it calibrates with much error at best.

Trees are not thermometers, but even thermometers have some serious measurement error problems.

Tree ring studies are a fad akin to phrenology and other discredited pseudosciences that has not dissipated as it should have decades ago.

Anyway, I put the numbers into an Excel spreadsheet and graphed the data and added a trendline. (If you would like a copy of the xls file, please ask for it in the comment section below.) As the world warms it is getting wetter. As Matt [...]]]> I found a link the other day to a government website with global mean precipitation data from 1900 to 2000. Of course, I can’t find the link now (please comment if you have the link, but first see the note at the end of the post).

Anyway, I put the numbers into an Excel spreadsheet and graphed the data and added a trendline. (If you would like a copy of the xls file, please ask for it in the comment section below.) As the world warms it is getting wetter. As Matt Ridley writes in his book The Rational Optimist:

If you take the IPCC’s [International Panel on Climate Change] assumptions and count the people living in zones that will have more water versus zones that will have less water, it is clear that the net population at risk of water shortage falls by 2100 under all their scenarios. (emphasis added)

Global mean precipitation (1900-2000)

10 yr average-global mean precipitation (1900-2000)

Even the EPA cites the IPCC (2007) to say much the same thing:

As global mean temperatures have risen, global mean precipitation also has increased. This is expected because evaporation increases with increasing temperature, and there must be an increase in precipitation to balance the enhanced evaporation (IPCC, 2007). Globally, precipitation over land increased at a rate of 1.9 percent per century since 1901, but the trends vary spatially and temporally. Over the contiguous U.S., total annual precipitation increased at an average rate of 6.1 percent per century since 1901, although there was considerable regional variability. The greatest increases came in the South (10.5 percent per century), the Northeast (9.8 percent), and the East North Central climate region (9.6 percent). A few areas such as Hawaii and parts of the Southwest have seen a decrease.

Crops may flourish with warmer climes and more CO2. There is some indication that in California some trees are increasing their ranges in response to this change. While increasing temperatures do have their downside, they also have positive benefits as well.

Note: it’s not U.S. and Global Mean Temperature and Precipitation on the United States Environmental Protection Agency‘s site. Nor is it State of the Climate-Global Analysis by the United States National Oceanic and Atmospheric Administration