Understanding Nutrient & Sediment Loss at Saxon Homestead Farm - 9. How the project started. Winter 2010/2011

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1 Understanding Nutrient & Sediment Loss at Saxon Homestead Farm - 9 Eric Cooley and Dennis Frame UW Extension/Discovery Farms Winter 2010/2011 Impact of UW Discovery Farms Research on: Agricultural Management at Saxon Homestead Farm, Public Perception, and Future Discovery Farms Research Site Criteria How the project started Saxon Homestead Farm, LLC (SHF) is a spring seasonal calving, pasture based dairy farm located one mile west of the town of Cleveland in Manitowoc County, Wisconsin. SHF is located in the Centerville Creek watershed, which is part of the Lake Michigan Basin. The selection criteria for this site included a strong emphasis on ability to monitor the water quality coming off of the grazed paddocks and the ability to determine how stocking density and management affected sediment and nutrient loss. The installation of surface water monitoring equipment began in July Two monitoring sites were installed in an intermittent stream running through the grazed paddocks. The monitoring design was an upstream/ downstream set-up. In addition to grazed paddocks, the upstream basin also contained tilled agricultural land and forest areas. The area monitored between the upstream and downstream areas were comprised of a high percentage of grazed paddocks, but also included the farmstead and a small portion of forested land. Because of an intensively tilled field that entered the upstream site via a road ditch just up from the monitoring site, a third surface water site was also installed to account for losses from this field which could influence the observed losses. The installation of the three surface sites was completed in October 2004 with the first runoff event occurring on December 10, In an effort to better understand the water budget of this farming system, a tile drainage monitoring site was installed adjacent to the downstream surface water site to collect water from equal basin sizes. The installation of the tile site began and was completed in mid-december. The tile monitoring site was running at approximately 50% capacity at the time of installation and continued to run during the duration of the testing period. Concurrent monitoring at both surface and tile sites was conducted until November 30, The monitoring shifted at SHF, after this initial large basin study, to a smaller, edge-of-field basin size. Data collected from this second phase of monitoring will be discussed in a subsequent set of fact sheets. The monitoring and research at SHF compiled much useful information on a variety of topics including an improved understanding of surface and tile drainage flow patterns in Northeast Wisconsin, land management influence on nutrient and sediment loss, and environmental factors contributing to management challenges in these landscapes. This information not only allowed the scientific community to gain a better understanding of agricultural losses associated with SHF s type of farming system, landscape and management, but it also allowed for producers to make more informed management decisions based on information learned at SHF. Information gathered and presented at local meetings also educated land conservation staff, elected officials, producers and the general public about the dynamics of agricultural production and its relation to environmental challenges in the area. The difficulties experienced while monitoring at SHF helped to better refine future Discovery Farm research sites. This fact sheet provides an overview of how data gathered at SHF was utilized to increase producer knowledge, bridge gaps between agricultural and environmental factions, and further determine site selection criteria for future Discovery Farms sites. This study has been summarized in nine fact sheets, which have been further summarized into two page briefs. These briefs and fact sheets are available on the UW Discovery Farms website (uwdiscoveryfarms.org) and through our office ( ). The website also contains information which has been summarized and put into slide presentations. These presentations provide a good overview of the lessons learned through this on-farm research and education program.

2 Major lessons learned Discovery Farms initially decided to study relatively large basins at SHF as compared to other studies performed by the UW Discovery Farms Program. Because of the large basin size, management changes implemented on a portion of the basin were potentially masked by the large volume of water flowing from the basin. Because of this, monitoring at SHF was switched to a smaller basin size in 2007 to more accurately assess management changes. This lesson was valuable for determining future monitoring basin size selection. The data collected from this initial large basin study, compared to the preliminary edge-of-field monitoring at a smaller basin size project, was evaluated to determine if edge-of-field monitoring could be scaled up to accurately estimate nutrient losses at larger basin sizes/intermittent stream delivery. This comparison indicates that nutrient and/or sediment loss from edge-of-field sites do not accurately estimate losses to the intermittent stream observed in the initial study. The edge-of-field data would highly overestimate the typical delivery observed from the intermittent stream monitoring. Both environmental factors and land management play crucial roles in the potential for sediment and nutrient loss. The monitoring at SHF demonstrates the importance of both surface and tile drainage with respect to sediment and nutrient loss. The comparison of surface runoff versus tile flow in the same basin quantifies the relative losses through the two pathways and better explains how environmental conditions and management can influence losses. As our understanding of when the losses can be expected to occur, management practices to minimize losses during these critical times can be implemented. The UW Discovery Farms Program and the Manitowoc County Discovery Farms Advisory Committee (see SHF-1) brought together diverse audiences and facilitated dialogue between the various groups. This was a unique forum for dialogue between researchers, producers, policy makers and the public to discuss Discovery Farms research and other issues relating to agricultural management and production. A variety of educational events including public meetings, tours of the farm and research stations, exhibits, and formal speeches proved to be valuable in facilitating education and open discussion between diverse audiences. Changes in agricultural management at SHF Management changes based on the data and information generated through Discovery Farms research is a crucial aspect to determine the success or failure of any research and outreach project. It is difficult to assess management changes based solely on Discovery Farms data and outreach, as other factors often contribute to management changes. Although influences apart from information learned through Discovery Farms may have played a role, the following changes were noted on the farm: At the same time as the project was being conducted at SHF, a comprehensive nutrient management plan was developed for the farm with assistance from Discovery Farms staff. Soil samples showing elevated phosphorus levels on some paddocks were shared with the farm staff. Discussions on where to best utilize nutrients from the manure storage were presented to staff and manure applications were reduced on fields with high soil test phosphorus levels. Incremental depth soil sampling was performed at this and other Discovery Farms sites to assess the stratification of phosphorus. A high stratification of phosphorus in the upper layers of the soil was observed in some paddocks, especially in the paddocks near the free stall barn where cows are overwintered. During the project with Discovery Farms, SHF decided to Figure 1. Waterway flow during late fall renovate paddocks to increase feed quality based on weed pressure and compaction in fields. The paddocks at SHF had not been tilled for a period of approximately 12 years. The incorporation of stratified phosphorus deeper in the profile provided additional information that paddock renovation could reduce soluble phosphorus loss and may have been a factor in the decision process. During late fall and spring periods, when precipitation events are common and the crusting and protection of directly deposited manure piles is minimal, it was noted that some manure in areas where water collected and

3 flowed was often moved by the flowing water (Figure 1). During summer and early fall, when cow pies crust, ample protection of the manure reduced movement with water. When this information was discussed with SHF, they devised a system of temporary fencing these flow concentration areas (in field waterways) off during critical time periods when the potential for movement is high. Additionally, SHF determined that they could schedule access to paddocks containing established flow paths during less critical time periods. SHF is very active in the community and they were very willing to share information gained on the farm with other producers in the area. SHF opened their farm to numerous tours and field day exhibits in addition to participating and hosting meetings organized and sponsored by SHF. It is hard to assess changes made on neighboring farms because of the information learned at SHF, but two factors are believed to enhance the information passed through this method. First, information delivered to local producers or passed word-of-mouth is likely to reach a broader audience than by educational events sponsored by the UW Discovery Farms Program and other outreach organizations. Secondly, this information is likely to have a higher level of adoption due to significance of local conditions, therefore more applicable to farms in the local region. Changes in public perspective of agriculture The formation of the Manitowoc County Discovery Farms Advisory Committee (see SHF-1) was very beneficial to the success of the UW Discovery Farms Program. The 15 meetings held between December 29, 2003 and June 6, 2006 covered initial Discovery Farms findings, local issues with agriculture, and facilitated discussion between agricultural producers, governmental agencies, and environmental groups. Some of the issues addressed in these meetings were: Understanding the phosphorus/cladophora issue in Lake Michigan. Prior to conducting this research, a common misconception was that increasing the size and amount of land in buffers along streams would dramatically reduce the amount of phosphorus entering surface waters. This management practice would have taken extensive amounts of land out of production and placed a high burden on the local/state tax base. Even worse than the loss of productive farmland and increased taxes; the research conducted by Discovery Farms indicated that increasing the size of buffers in Manitowoc County and other counties in Northeastern Wisconsin will very likely have limited effect on reducing phosphorus losses. This is because of the high ratio of dissolved phosphorus to particulate phosphorus in runoff samples. Buffers are very effective at reducing particulate phosphorus loss because they trap soil particles before they reach surface water. However, buffers have little to no effect on dissolved phosphorus, which is carried in the water. This research combined with discussions between producers and environmental groups focused on identifying viable options for reducing dissolved phosphorus losses. Discovery Farms data is factual, honest, and complete. Discovery Farms staff and farm personnel are committed to collecting factual data regardless of the results. This empowers all the participants to improve management and make better decisions. It was demonstrated that all testing is 100% automated, equipment is locked, and it is difficult to modify samples. Only qualified Discovery Farms or USGS personnel have access to locked research sites and furthermore, pictures of bottles for each storm event are taken at the analysis laboratory. Trying to modify these samples to correspond to changes in flow rate would be extremely difficult, if not impossible. Because this concern was revealed in committee meetings, Discovery Farms personnel were able to address this concern in subsequent meetings with the public. In addition, Discovery Farms data was presented showing substantial losses under a wide variety of management systems and conditions. Finding ways to educate the public on environmental issues in the area. A groundwater model was purchased to better inform youth and the general public on where drinking water comes from and the potential contamination issues that can negatively impact groundwater resources. Discovery Farms staff attended county fairs and other public events to provide additional education. Discussing other topics at committee meetings including monitoring challenges at Discovery Farms sites, manure spill response procedures, development of a soil moisture risk management assessment tool, anaerobic digesters, flush systems, pathogen testing, state and local agricultural regulations, nutrient management planning, and certification at the county level for custom manure haulers. In addition to Manitowoc County Discovery Farms Advisory Committee meetings, local meetings were conducted for the County Board, municipal officials and the Towns Association. Each of these meetings helped to educate the public on modern day agriculture and how farmers are using BMPs to protect the environment while growing their operations. Farm tours were organized through the Manitowoc Extension office and Discovery Farms to further educate the public on how farms operate and implement measures to protect the environment. Numerous newspaper and newsletter articles were written, and interviews were conducted with radio, television and newspaper media.

4 Changes in research site criteria for future Discovery Farms sites The lessons learned while monitoring at SHF has improved our site selection criteria for future monitoring stations: Concurrent surface water and tile monitoring in a basin. The concurrent monitoring of both surface water and tile drainage proved to be very beneficial at SHF. Although many difficulties were experienced with the tile monitoring in the location selected, the comparison of surface runoff and tile flow greatly improved the data as well as the information generated from this project. Further analysis of the timing of runoff in surface and tile also indicated that surface water flow at the downstream site was strongly influenced by the ability of the tile to remove water. In other words, when the tile system was at or near capacity, surface water flowed. This data also identified a strong interconnection of preferential flow between the surface and the tile. The timing and pathway of nutrient loss can be very different in surface runoff as compared to tile. In tile drained agricultural landscapes, it is important to utilize both surface and tile drainage monitoring, when possible, to accurately assess the potential loss of sediment and nutrients so management practices affecting losses can be better understood. Close to power (near power lines or buildings). Two of the four monitoring sites (upstream and ditch) at SHF had direct-wired, AC power. The remaining two sites (downstream and tile) were solar powered. Maintaining adequate power to run the downstream and tile site proved to be challenging at times. Because the tile had longer flow periods and intermittent stream flow as compared to other edge-of-field surface sites, the power demand was higher from the continuous sampling and operation of the heat tapes. Although large solar panels and additional batteries were used, low voltage situations were often experienced during spring runoff and other high flow periods. Additionally, the long flow duration during freeze/thaw periods when solar recharge was low, further compounds the power issue. It should be suggested that direct-wired power be utilized whenever possible in tile drainage or intermittent stream monitoring settings. Easy access by road (able to plow in winter). Two of the four monitoring sites (upstream and ditch) had relatively good site access. The ease in accessibility made sample collection and snow removal much more effortless as compared to the downstream and tile sites which were far from a plowed road. A high amount of staff hours were spent accessing these sites during snow or high moisture conditions which hampered vehicle travel. SHF was very helpful with plowing a field road that reduced some of the travel time, but snowmelt and high moisture conditions made access to the site only possible with an ATV or by foot due to the high clay content of the soils. If possible, locate monitoring sites as close as possible to well established access roads. 40 acre basin or less. The basin sizes of both the upstream (495 acres) and downstream (641 acres) proved to be challenging for edge-of-field surface and tile drainage monitoring. The flow volumes made it difficult to assess changes in management on the landscape on a small scale due to the dilution effect. Additionally, some storms were near overtopping the wing wall and earthen dam because of the large volumes of runoff. The intensively tilled site monitored in the study was a very manageable size of 17.6 acres and allowed for adequate sample volume and standard sizing of monitoring flumes for this basin. Single field per basin if possible. Although this farm monitored grazing paddocks as compared to commonly monitored crop fields, it was again apparent that the multitude of paddocks that comprised this basin made it difficult, if not impossible, to determine activities going on in a single paddock. Since each paddock was typically less than 5 acres, a single paddock only comprised less than a hundredth of the total basin area. Since cow access, timing, and nutrient applications varied on each paddock, the task of correlating water quality to agronomic and management data was a challenge. The shift at SHF to smaller basins comprised of only a few paddocks made this task much more plausible. Sites with single fields or paddocks would be optimum for future site selection. All/majority of agricultural land in the basin under control of participant. The data discussed in this series of fact sheets show the importance of having the land in the monitored basin under the control of the participant. The intensively tilled site monitored, which was not under the control of SHF, had some of the largest losses of sediment and nutrients. Since no agronomic data from this land was gathered, other than general observations taken in the field, it was hard to understand the timing and magnitude of the loss measured. Having access to management and agronomic data on all land in a monitored watershed should be a significant criterion for future site selection. No backwater (good slope away from surface site and clear discharge path for tile). It is crucial to ensure proper get-away conditions from the monitoring equipment so as not to get backwater in the flume that will cause erroneous flow measurements. Because of the low slope downstream of both the upstream and downstream sites, snow had to be cleared downstream approximately 300 feet at the upstream site (K1) and 100 feet from the downstream site (K2) to prevent backwater conditions during snowmelt. Even with these efforts taken to clear the downstream path, backwater conditions were created as temperatures

5 Figure 2. Icing due to backwater conditions dropped below freezing at night and the upper layer of the stream would freeze and subsequent water would freeze on top of it creating the backwater condition (Figure 2). Many staff hours were required to maintain these sites during snowmelt events as the backwater would freeze at night and had to be cleared out early the next day before flow would begin. The backwater conditions at the tile monitoring site created challenges to accurately measure flow during the entire monitoring period, as discussed in fact sheet SHF- 8. Due to the backwater conditions, additional equipment was installed to measure velocity, but maintaining equipment functionality was difficult. From both a surface and tile perspective, locations that have a potential for backwater conditions should be avoided as much as possible. Cooperative and good recordkeeping participant. SHF and its crop consultant had a good recordkeeping system and always were available to share their records and management information with Discovery Farms staff. Without this type of cooperation and comprehensive recordkeeping of what happened on the land, linking water quality data to land management would be impossible. Perform comprehensive evaluation of basins to be monitored and continue evaluating during study period. Perspective sites meeting selection criteria should be closely evaluated for potential problems with monitoring. A comprehensive field walk should be performed to look for tile blowouts both upstream and downstream of potential monitoring sites in tile drained landscapes and other land features which can skew results. The landowner or operator that runs the land can be a good resource in identifying potential problems. Tile blowouts that developed during the monitoring period were identified by both SHF and Discovery Farms staff and were fixed soon after identification. It is likely from the data collected, that other tile blowouts existed but were not identified.

6 The data presented in this article were provided by the U.S. Geological Survey as part of a cooperative agreement with the UW-Discovery Farms Program. This material is based upon work supported by the National Institute of Food and Agriculture (NIFA), U.S. Department of Agriculture, under Agreement No Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture. This fact sheet is part 9 of a 9 part series and can be found along with the rest of the fact sheets on the web at: or by calling the UW-Discovery Farms Office at by the Board of Regents of the University of Wisconsin System. University of Wisconsin-Extension is an EEO/Affirmative Action employer and provides equal opportunities in employment and programming, including Title IX and ADA requirements. Publications are available in alternative formats upon request.