From jamjohnson@ucdavis.edu Tue Mar 16 22:05:27 1999 Date: Tue, 16 Mar 1999 12:00:20 -0800 From: James Johnson Reply-To: SOIL QUALITY To: SOIL QUALITY Subject: [soil-quality] [Fwd: FW: New Study Shows Over-Fertilization Linked To Soil Death] Good article on the long term effects of synthetic fertizers. James Johnson UC Cooperative Extension [ Part 2: "Included Message" ] Date: Tue, 16 Mar 1999 11:34:32 -0800 From: Mark Musick To: Community Food Security Coalition Subject: FW: New Study Shows Over-Fertilization Linked To Soil Death [ The following text is in the "iso-8859-1" character set. ] [ Your display is set for the "US-ASCII" character set. ] [ Some characters may be displayed incorrectly. ] Agricultural and Consumer Press Service >College of Agricultural and Life Sciences >440 Henry Mall >Research Division/University of Wisconsin-Madison >Madison WI 53706 (608) 262-1461 > > For Immediate Release > For More Information: > Phil Barak (608) 263-5450 > PWBARAK@FACSTAFF.WISC.EDU > >ACID LINKED TO SOIL AGING >Thirty-seven years of data collected from a plot at the University of >Wisconsin-Madison's Arlington agricultural research station is >yielding alarming results: acidification from excess fertilizer is >wearing out the soil. > >Phillip Barak, UW-Madison associate professor of soil chemistry and >plant nutrition, said he is part of a team carrying on research that >started in 1962. Barak and his colleagues have found the cation >exchange capacity, or the soil's ability to hold onto small bits of >calcium, magnesium and potassium, decreases because of soil acidity. >"This change is irreversible," he said. > >According to Fred Madison, UW soil science professor, this is >important news for farmers. "Now you've got a whole path of >destruction," he said. Producers may have overlooked the danger that >excess nitrogen poses to groundwater, but evidence that it may also >permanently damage the soil is beginning to garner attention, >Madison said. > >Barak said health experts have long known the role that nitrogen >plays in blue baby syndrome, a condition in which high levels of >nitrogen inhibit the blood's ability to transport oxygen. Barak said >soil becomes more acidic when nitrogen sources, whether from urea, >legume plowdown - such as alfalfa and red clover - or commercial >fertilizer are not completely used up by the crop. > >This excess nitrogen becomes nitric acid, which destroys the soil's >vital ability to retain the calcium, magnesium and potassium >necessary for crop growth. Instead, these nutrients leach out of the >soil and into the groundwater. Although they are harmless, they do >cost money to replace - a price that Barak estimates at 20 percent of >what farmers normally spend on nitrogen fertilizers. > >According to Barak, the United States has a 50 percent applied >nitrogen efficiency rate. This means only half of the nitrogen >applied by farmers is actually taken up by the plants, leaving the >other half to become nitric acid, he said. "That's like a tanker >truck of nitric acid being dumped on a field," Barak said. > >These tons of unneutralized nitric acid age the soil very quickly, >according to Barak. He said the soil at his Arlington test site has, >in 30 years of "normal" agricultural acid inputs, aged the equivalent >of 5,000 years with natural source acid inputs. > >Barak said the aging is remarkable considering the age of the soils. >"Keep in mind these soils have only been in existence for 10,000 >years," he said. > >Barak said the fine soils of Wisconsin are "tender," and the very >qualities that make them fertile also make them vulnerable. They are >easily dissolved by acidity, he said. According to Barak, if excess >nitrogen inputs continue, unneutralized, northern soils might soon >become like the sandy, less productive soils of the southeast region >of the United States. > >"With the long term, over-application of nitrogen, we run the risk of >irreparably damaging the soil," Madison said. > >But Barak said the news is not all bad. He cited two ways farmers >can better care for their valuable soil. The first, and preventative, >measure is to use nitrogen more efficiently. Producers should account >for all sources of nitrogen, and adjust their commercial inputs >accordingly. Excess nitrogen not only acidifies, it can leach into >groundwater or run off into surface water. > >The second, and remedial, measure is applying agricultural lime. >Liming can neutralize the damaging acid and protect the fields. >"Agliming has been known for 3,000 years," Barak said. "Use it. It's >like TUMS for the soil." By closely monitoring pH levels and >appropriately applying agricultural lime, farmers can greatly retard >what Barak refers to as "accelerated soil weathering." > >Since 1950, Barak reports that nitrogen use, as well as agricultural >production, has skyrocketed. The United States is locked into a >system of high production that cannot be reversed without serious >negative implications, he said. The result is that farmers must >learn to be more attentive to their treatment of the soil. > >### >Writer: Andy Napgezek, 836-6651 >aanapgez@students.wisc.edu > >This story first appeared in the March 3, 1999 issue of the Badger >Herald, an independent student newspaper at the University of >Wisconsin-Madison. > ><<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< >Michele Gale-Sinex, communications manager >Center for Integrated Ag Systems >UW-Madison College of Ag and Life Sciences >Voice: (608) 262-8018 FAX: (608) 265-3020 >http://www.wisc.edu/cias/ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >If you knew what life was worth, you >would look for yours on earth. --Bob Marley > >To Unsubscribe: Email majordomo@ces.ncsu.edu with the command >"unsubscribe sanet-mg". >To Subscribe to Digest: Email majordomo@ces.ncsu.edu with the command >"subscribe sanet-mg-digest". > >All messages to sanet-mg are archived at: >http://www.sare.org/san/htdocs/hypermail > >___________________________________________________________________ >You don't need to buy Internet access to use free Internet e-mail. >Get completely free e-mail from Juno at http://www.juno.com/getjuno.html >or call Juno at (800) 654-JUNO [654-5866] > > Annalee Cobbett, Atty Chair, FarmCity Alliance coban@seanet.com (206) 626-0266 Fax (206) 626-6477 Views expressed on the farmcity listserv may or may not reflect those of myself or the FarmCity Alliance.