DEAR NEW FARM:
I am a Ph.D. student at the University of Florida and am taking
a class on world agriculture. The instructor is very dogmatic about
the use of synthetic nitrogen. I would appreciate any information
you might have as well as other sources you can lead me to that
I can use in this class to provide the other side of the argument.
You are probably aware that UF just cut the ribbon on the first
dedicated organic research department of any land grant university
in the U.S: www.napa.ufl.edu/digest/stories/organic0301.html.
Someone over there might offer you some good cannon fodder, or even
better, help you to build a bridge between the mainstream agriculture
department and the folks who have got it right!
We get frustrated ourselves when we hear reporters repeat as statement
of fact that synthetic nitrogen is necessary to feed a burgeoning
population (NPR, no less) every time they do a peice on Fritz Haber
or some other related historical figure connected to the synthesis
We believe that the poor farm management practices so ubiquitous
across the American landscape are largely due to who has traditionally
funded land grant universities: the companies that make pesticides
and herbicides, synthetic fertilizers, and are now pushing transgenic
The late Donella Meadows wrote an excellent piece for the September/October
2000 issue of Organic Gardening magazine entitled Our
Food, Our Future which lies bare the myth of synthetic inputs
and GMOs as the only hope for feeding a burgeoning world population.
After derailing this notion, Meadows explains why, and how, organic
agriculture can do the job just fine.
The Rodale Institute’s Farming Systems Trial® and Compost
Utilization Trial have produced a number of peer-reviewed research
papers that demonstrate how nitrogen is more efficiently utilized
in an organic system. Among these findings, says research agronomist
Dave Wilson, are the facts that:
- Synthetic fertilizers make nitrogen available to crops very
quickly. This makes them more prone to leaching, which can pollute
surrounding land and water—think dead zones in the Chesepeak
Bay and Gulf of Mexico. Organic nitrogen sources are released
slowly throughout the growing season and contribute to N reserves
in the soil. Organic amendments can also improve soil structure
and stimulate soil biological processes, particularly in degraded
- Synthetic nitrogen fertilizers speed up the decay process of
organic matter so that it is released in the atmosphere as carbon
dioxide, a major greenhouse gas. In an organic system, carbon
is stored in soil and plant tissue and is recycled.
- Leguminous cover crops, an integral part of an organic system,
fix nitrogen from the earth’s atmosphere and accumulate
soil carbohydrates through plant biomass. These “green manures”
also improve soil structure and help prevent erosion. They go
to work deep in the soil, fostering symbiotic relationships between
soil microbes and living roots; beneficial products of these relationships
include mycorrhizal fungi, which bolster a plant’s ability
to take up nutrients and water, and glomalin, a glue-like substance
that binds soil particles together and a contributes to tilth
For more on the subject, you can purchase the publication The
Rodale Institute Farming Systems Trial™ in our bookstore.
Some of the Institute’s peer reviewed articles on this subject
- Hu, S., Grunwald, N., Van Bruggen, A., Gamble, G., Drinkwater,
L., Shennan, C., and M. Dement. 1997. Short term effects
of cover crop incorporation on soil carbon pools and nitrogen
availability. Soil Science Society of America Journal 61(3):901-911.
- Pallant, E., Lansky, D., Rio, J., Jacobs, L., Schuler,
G., and W. Whimpenny. 1997. Growth of corn roots under low-input
and conventional farming systems. American Journal of Alternative
- Drinkwater, L.E., Wagoner, P. and M. Sarrantonio.
1998. Legume-based cropping systems have reduced carbon and nitrogen
losses. Nature 396: 262-265.
- Douds, D., and P. Millner. 1999. Biodiversity of Arbuscular
Mycorrhizal fungi in Agroecosystems. Agriculture, Ecosystems and
- Drinkwater, L., Janke, R., and L. Rossoni-Longnecker.
2000. Effect of tillage and intensity on nitrogen dynamics and
productivity in legume based grain systems. Plant and Soil 227(2):99-113.
us with comments, suggestions and questions.