Agriculture Reference
In-Depth Information
agriculture as an ecosystem means not only managing for marketed products but
also for socially valued ecosystem services (Antle and Capalbo 2002, Robertson
et al. 2004, Farber et al. 2006, Swinton et al. 2006, 2007; Swinton et al. 2015,
Chapter 3 in this volume). Examples of such services include farm management for
GHG mitigation via carbon sequestration and reduced greenhouse gas emissions
(Robertson 2004), water-quality improvement via reduced nutrient and pesticide
leaching and runoff (Hamilton 2015, Chapter 11 in this volume), and biodiversity
habitat that enables enhanced biocontrol of agricultural pests by natural enemies
and crop pollination by wild pollinators (Landis et al. 2008; Landis and Gage 2015,
Chapter 8 in this volume).
Some environmentally beneficial agricultural practices have low and uneven
levels of adoption by U.S. farmers. For example, more complex crop rotations are
known to provide environmental benefits related to pest protection and nutrient
conservation. Yet in 1997, 53% of U.S. corn (
Zea mays
L.) and soybean (
Glycine
max
L.) acreage was in a simple 2-year corn-soybean rotation, with only 10% in
a rotation that included small grains (Padgitt et al. 2000). Only 31% of U.S. corn
farmers practiced soil testing in 2002 (Christensen 2002). In California, by 2007
the adoption of organic farming remained under 2% of farmers and less than
1% of the state's agricultural value; the number of California farmers becoming
organic-certified was nearly offset by the number allowing their certification to
lapse (Serra et al. 2008).
Agricultural research over several decades, including 20 years at KBS LTER,
has identified clear environmental benefits of rotations of corn, soybean, and wheat
(
Triticum aestivum
L.) with a winter cover crop and reduced fertilizer application.
Nonetheless, the 2008 Crop Management and Environmental Stewardship Survey
linked to the KBS LTER (Jolejole 2009, Ma et al. 2012) found that Michigan corn
and soybean farmers devoted only 8% of their land to wheat and 5% to winter
cover crops, while only 22% reported applying fertilizer at rates below those rec-
ommended by university extension and only 21% applied pesticides at rates below
label recommendations (Ma et al. 2012).
Some environmentally beneficial practices have been readily adopted by farm-
ers. In the same 2008 Michigan farm survey, 82% of farmers reported that they prac-
ticed reduced tillage (compared to moldboard plow), including 55% who practiced
no-till in some years (Jolejole 2009). Eighty-seven percent also reported scouting
for insect pests to guide pesticide decisions. At the national scale, U.S. conserva-
tion land set aside through the CRP was fully enrolled shortly after its inception in
1985 (ERS 2012b). And a high enrollment rate has persisted in spite of increasingly
stringent environmental criteria. Since EQIP was created in 1996, it too has seen
more farmer interest in environmental cost share programs than its budget or acre-
age caps allow.
Notwithstanding the success of these programs, the combination of national
and local patterns of low adoption of many (but not all) environmentally beneficial
cropping practices raises the questions: Why are rates of adoption of environmen-
tally beneficial farming practices not higher? Why are some practices adopted but
not others?
