Reports Iowa State University
(funded by The
Leopold Center for Sustainable Agriculture)
Leopold Center for Sustainable Agriculture's
Support for Iowa Manure and Nutrient Management Efforts (1/98)
It is the goal of the Leopold Center for Sustainable
Agriculture to develop socially and environmentally sound farming
systems that profit the farmer and the farm community. Center initiatives
are closely integrated with its systems approach to agricultural production,
including research, demonstration, and education efforts such as keeping
crop inputs on-site through effective streamside management and maximizing
profitability of highly erodible land through grazing systems.
The Center has devoted considerable resources to development of animal
management systems adaptable to all scales of farming, especially
those who desire lower capital cost and management intensive systems,
specifically farm owner-operators. The Center's programs have emphasized
utilizing manure in crop production in a manner that minimizes off-site
pollution while maximizing profitability.
In addition to supporting ISU Extension's Statewide Manure Management
Education Initiative, the Leopold Center for Sustainable Agriculture
has provided more than $967,990 (1988-1997) for manure and nutrient
management research, demonstrations, and educational workshops. This
includes 15 competitive grant projects, five years of research support
for the Leopold Center's Manure Management Issue Team, 20 conferences
and workshops attended by over 2,500 farmers, landowners, educators,
and researchers, and facilities construction for the swine hoops systems
initiative. An additional $108,000 is conditionally committed for
ongoing grants, and$150,000 is conditionally committed for swine hoops
Manure and Nutrient Management Competitive Grants,
past and present (Researcher affiliation
listed is for the period of the project and may have since changed.)
Evaluation of Organic Soil
Amendments for Certified Organic Vegetable and Herb Production.
Delate. Year 2 of 3. $12,500 (99-50); ISU Horticulture and Agronomy
After analysis for macronutrients, moisture and carbon/nitrogen ratio,
several composts will be applied to productions systems and the composts
compared through an evaluation of their impact of product yields,
pest status, soil health indicators, product quality and economics.
On-farm sites have been established near Kanawha and Ames, and a research
farm site has been established in southeast Iowa at the Muscatine
Island Research and Demonstration Farm. Types of amendments being
tested include poultry litter, feathermeal, BioCalŪ and conventional
Nitrogen Conservation in Swine
Manure Composting: Land Application Systems. Tom
Richards, Tom Loynachan, and C.A. Cambardella. Year 2 of 2. $31,000
(99-62); ISU Agricultural and Biosystems Engineering, Agronomy and USDA-ARS
National Soil Tilth Laboratory.
By quantifying nitrogen transformations as swine
manure is composted with corn stalks and by quantifying carbon and
nitrogen mineralization when composts of different maturities are
applied to soil, researchers can understand how to develop compost
products that synchronize nitrogen release and crop uptake and improve
overall soil quality. In the first six months of this study, special
nitrogen analysis and KCI extraction methods and special laboratory
composting reactors were designed to deal with the high variability
of the samples. Functional pilot scale reactors were constructed and
initial analytical trials were conducted.
Socio-technical and Environmental
Dimensions of Swine Manure Management Decisions. C.
Hinrichs and T. Richards. Year 2 of 2. $7,598 (99-69); ISU Sociology
and Agricultural and Biosystems Engineering.
Qualitative field interviews have been conducted
during the spring of 1999 in the Raccoon River and Iowa River watershed
regions to examine how farm operation characteristics and personal
views on environment and technology influence swine producers
manure management decisions on their farms. The research includes
questions in four main areas: the biological, physical, social and
economic characteristics of the farm operation; farmers perceptions
about manure and features of their manure handling systems; farmer
environmental and watershed perceptions, and current challenges and
concerns of farmers.
Development and Implementation of
Cost-effective Fertilization and Tillage Practices for Improving
Soil Quality in Corn-Soybean Rotations,
1 year completed, $24,450, with 2 more years planned, $48,900 (#98-36);
Antonio Mallarino, ISU Department
Project objectives include development of phosphorus,
potassium, and starter fertilization recommendations for corn and
soybean under different tillage systems; evaluation of improved diagnostic
tools to assess P and K soil fertility in no-till and ridge-till;
economic analysis of alternative fertilization and tillage practices;
and demonstration of a methodology for on-farm research and demonstrations
based on precision agriculture technologies.
Statewide Manure Management Education
Miller. Year 3 of 3. $25,000 (98-51); ISU Agronomy
Under leadership from ISU Extension, the Leopold
Center, Iowa Veterinary Medical Association, soil and water conservation
districts, and the Iowa Independent Crop Consultants' Association,
this project will use intensive workshops with individualized participant
plans to encourage appropriate decision making about utilization of
In Iowa, manure management is rapidly becoming more complex as an
economic, environmental and political issue. Iowa has the largest
number of hogs of any state, it ranked fourth, as of 1994, in cow/calf
production and is among the top ten states for numbers of all conventional
livestock. For small to moderate-sized mixed crop and livestock farms,
optimizing manure use for crop nutrients can be critical for maintaining
profitability as the cost of all purchased inputs rises. The 1995
Iowa Farm and Rural Life Poll indicates that only 48% of crop producers
with livestock adjust commercial fertilizer rates where manure has
been applied. Excess soil fertility attributable to addition of fertilizer
without taking adequate credit for manure applications is a potential
surface and groundwater pollution risk over much of the state.
In the 1997 county extension program planning process, 49% of counties
named manure management as their highest priority issue for programming.
Field and campus extension staff have responded by developing a statewide
manure management education initiative that is an immediate, critical
need for Iowa producers. Objectives of the Statewide Manure Management
Education Initiative are to reduce potential nitrate and bacterial
pollution of surface and shall groundwater, and to enhance farm profitability
by increasing the use of on-farm resources. In addition to ISUE, the
initiative is supported by the Iowa Veterinary Medical Association,
the Iowa Independent Crop Consultants Association, and the Leopold
Center for Sustainable Agriculture.
During its first year of implementation (1997), 140 workshops on Manure
Nutrient Management were conducted across the state, reaching nearly
800 livestock producers. Workshops will continue to be scheduled annually,
during the winter, in all Iowa counties through 1999. All farmers
with livestock operations, and crop producers who want to use a nearby
available manure source, may attend the workshops free of charge.
Each workshop is taught by a team of Extension Field Specialist in
the area of crop production, ag engineering, and farm management.
Workshops use an innovative "fishbowl" format that fosters
interaction and discussion among instructors and participants. Participants
learn technical details of developing a "typical" management
plan for their area, then work on individualized plans based on their
own field and manure inventory information.
On their exit surveys, 26% of participants rated the workshops as
"good" and 73% as "excellent" or "superior".
Ninety-nine percent said they would recommend it to others. The majority
planned to change important aspects of their manure and nutrient management
based on what they had learned at the workshop. Follow-up surveys
will continue to evaluate the effectiveness of the program.
Impacts of the Use of Poultry
Manure for Agricultural Production Systems. Rameshwar
Kanwar. Year 2 of 3. $ 18,300 (99-68); ISU Agricultural and Biosystems
The project will monitor two application rates of
poultry manure and commercial fertilizer nitrogen on corn and soybean
for leaching of NO3-N (nitrate-nitrogen) PO4-P
(phosphate-phosphorus) and pathogenic bacteria to subsurface drainage
water and shallow groundwater. Initial treatments of 150 lb. N/ac.
from poultry manure resulted in the lower NO3-N concentrations
in tile water than treatments with 150 lb. N/ac. from UAN and 300
lb. N/ac from poultry manure. PO4-P and fecal coliform
concentrations in tile water from the 300 lb. N/ac. poultry manure
were similar to 150 lb. N/ac. treatments either from poultry manure
or from UAN fertilizer.
Demonstration of Swine Carcass
Composting as Part of an Environmentally Friendly Production System.
Year 1 of 2. $ 23,800 (2000-33); ISU Agricultural and Biosystems Engineering
Swine carcass composting demonstrations will be conducted
at the ISU Rhodes Research Farm and the Lauren Christian Swine Farm
near Atlantic. The projects will examine deep bedding, various co-composting
materials (wood chips, straw and soybean residue), finishing swine
mortality (Rhodes) and sow farm and nursery pig mortality and afterbirth
Crop Response to Selected Micronutrients
in Iowa. Randy
Killorn. Year 1 of 3. $25, 696 (2000-04); ISU Agronomy
The purpose is to update ten-year-old research on
crop response to micronutrients. At least ten sites will be evaluated,
and the micronutrients to be tested will be decided upon in consultation
Soil Amendment Effects on Crop-Weed
Liebman and Tom Richard. Year 1 of 3. $ 18,430 (2000-11); ISU Agronomy
and Agricultural and Biosystems Engineering
This research will investigate how amending soil
with compost made from hog manure and cornstalks affects the growth
and competitive ability of three weed species commonly found in Iowa
corn fields (giant foxtail, velvetleaf and waterhemp). The manure
and cornstalks will come from swine hoop structures, which are increasingly
popular with Iowa pork producers.
Livestock and the Environment
Project in Sioux County. Kris
Kohl, Joel DeJong. Year 1 of 3. $ 29,545 (2000-36); Buena Vista
and Plymouth County Extension, Storm Lake and LeMars
The Northwest Iowa Extension environmental team will
investigate through survey and focus groups the barriers that deter
producers from utilizing manure as a crop nutrient, and test a new
pit-sampling method for producer acceptance. The goal is to define
strategies that would measurably and positively impact manure management
Optimizing Swine Hoop Manure
Management for Soil Quality and Crop System Performance. Tom
Richard, Matt Liebman, Rick Exner and C.A. Cambardella. Year 1 of
3. $ 29,432 (2000-42); ISU Agricultural and Biosystems Engineering and
Agronomy, Practical Farmers of Iowa and USDA-ARS National Soil Tilth
Researchers plan to use on-farm and research station
experiments to evaluate the impacts of alternative hoop manure management
strategies (corn/soybean rotation, composted manure, bedded manure,
spring and fall applications) on soil quality and cropping system
performance. Observations will include farm management data, compost
and bedding composition, soil biochemical properties, soil microbial
biomass, crop biomass and macronutrient content, and seed yield data.
Dairy Manure Quantification
and Characterization in Grazing Systems;
Wendy Powers and Marjorie Faust.
Year 2 of 2. $33,726 (99-16); ISU Animal Science
Good water quality is a key resource
for Iowas future, and the use of Best Management Practices can
help to minimize the degradation of water quality. Currently there
are no guidelines for determining pasture stocking rates and storage
needs that will protect water quality for intensive grazing dairies.
Current estimates of manure excretion are based on a limited amount
of outdated research and do not adequately reflect livestock operations
of today. Both the animals and the management practices have changed
dramatically over the last two decades. Increased environmental awareness
dictates that producers manage manure properly, which, in turn, requires
that producers be provided with accurate information regarding quantity
and composition of manure excretions.
The proposed research project will focus on intensive grazing systems
for dairy cows. These operations, in particular, need data on manure
composition and quantity. Widely used table values (ASAE, 1994) were
generated based on research conducted in confinement systems where
cows were fed a combination of forage and concentrate. Thus, the effect
of a total forage diet have not been assessed. Graziers need to have
at their disposal the tools necessary to make environmentally sound
decisions regarding stocking rate and storage capacity of milking
area washwater and storage collection. Unique to climates such as
Iowa is the additional need to have information available to graziers
that documents manure quantity and composition during periods when
pasturing is not possible and animals must be housed with manure collection
and storage. During this time, the diet is much different than that
during the grazing period, representing a combination of forage and
concentrate in the diet.
Two grazing dairy operations will be used in this project, each representing
different breeds of cows. The project entails year-round sample collection
of milk and manure from cows selected within each herd. Fecal and
urine samples will be collected monthly from the selected cows and
analyzed for water quality measures such as nitrogen, phosphorus,
and chemical oxygen demand. Influence of milk components and additional
cow factors such as bodyweight, breed, parity, and production level
on manure constituents will be evaluated.
Based on the quantified influence of these factors, prediction equations
will be developed for use in estimating manure composition and quantity.
Data generated from the equations can then be assembled into table
format, thereby providing regulatory agencies and producers with better
estimates that represent age and weight ranges as well as dietary
differences among animals than currently available. Nutrition-based
models will be evaluated on their ability to accurately predict excretions
from cows in a grass-based system. Verification of some of the currently
available models will provide additional tools for use in planning
and predicting the environmental impact of management decisions in
For more information, contact the Leopold
Center at 515/294-3711 or email email@example.com