Progress report for LNE25-499R
Project Information
Project Focus
Healthy, fertile soils are the foundation for forage production and an essential component in maximizing forage quality and productivity. However, fertilizer applications can be a major expense for producers, many of whom are working with tight margins and looking for ways to reduce expenses. As a result, a growing number of forage and livestock producers throughout the Northeast are interested in alternative ways to provide fertility for forage systems other than commercial fertilizers. In the 2020 Maryland Forage Needs Assessment, producers listed ‘high fertilizer costs’ as the second highest factor limiting their ability to successfully improve and/or manage forage production.
Possible alternatives that could be used in place of commercial fertilizer may include manure, poultry litter, compost, or biological amendments. These alternative soil amendments may provide a more economical source of nutrients for forage and livestock producers, allowing them to continue to meet fertility needs to optimize forage growth. Although there is a large body of literature showing success with using different soil amendments on forage crops, there has been limited research evaluating the effect of a wide range of different soil amendments on forage and soil characteristics under both grazing and hay production systems, particularly in the Northeast region.
Solution and Approach
A comprehensive analysis evaluating different soil amendments is necessary for producers to feel confident in deciding which fertility strategy will be most successful and most economical for their operation. The objective of this project is to compare forage yield, forage quality, economics, botanical composition, grazing selectivity, soil fertility, and soil health metrics for different soil amendments under both grazing and hay production systems. Soil amendments will be evaluated against a no-fertility control and will include commercial fertilizer, poultry litter, manure, compost, and a biological amendment. Amendments will be applied as replicated treatments onto established, cool-season perennial forages under both grazing and hay production systems and evaluated over multiple locations and growing seasons to account for annual weather variability. Forage yield, forage quality, botanical composition, soil fertility, soil health, grazing preferences, and economics will be measured within each system. An economic analysis will be completed to compare the inputs, outputs, and relative success of each treatment.
As the study progresses, producers will be invited to an annual field day at the research site. Preliminary results will be shared and producers will be invited to provide feedback and discuss research findings. Two producers interested in soil health and alternative fertility sources will be recruited to serve as on-farm education sites and will each host an on-farm field day. At the conclusion of the study, results will be disseminated to producers through a combination of direct (farm visits, field days, meetings, demonstrations) and indirect (articles, webinars, videos) methods.
The objective of this project is to compare forage yield, forage quality, economics, botanical composition, grazing selectivity, soil fertility, and soil health metrics for different soil amendments. A growing number of Northeast forage and livestock producers are interested in alternative ways to improve soil health and fertility besides the use of commercial fertilizers; possible alternatives may include the use of poultry litter, manure, compost, or biological amendments. This project will evaluate these four different soil amendments against commercial fertilizer and a no-fertility control under both grazing and hay production systems to help producers make economical, research-based fertility decisions.
Healthy, fertile soils are the foundation for forage production and an essential component in maximizing forage quality and productivity (Collins et al., 2017). The Northeast is home to over 10,000 dairy, 39,000 beef, 13,000 small ruminant, and 60,000 hay production operations, all of whom rely on the health and fertility of their soil to produce high-quality forages to feed their livestock or sell as harvested forage products. The importance of soil health and fertility to producers was evident in the 2020 Maryland Forage Needs Assessment, as ‘soil health and fertility’ was the highest-ranking topic of interest reported by livestock and forage producers.
However, fertilizer applications can be a major expense for producers, many of whom are working with tight margins and looking for ways to reduce farm expenses. This is especially relevant for farms in the Northeast region, as many of these operations are smaller-scale, forage-based operations. In the 2020 Maryland Forage Needs Assessment, livestock and forage producers listed ‘high fertilizer costs’ as the second highest factor limiting their ability to successfully improve and/or manage forage production on their farm. In recent years, fertilizer prices have undergone drastic increases, with prices increasing as much as 110 to 156% from the end of 2020 through the middle of 2022 (“USDA Production Cost Report,” 2024). Although prices have come down slightly from their peak in 2022, fertilizer prices remain around 36 to 68% higher compared to late 2020, making it much more challenging for producers to justify the cost of fertilizer and to meet soil fertility needs within forage production systems.
As a result, a growing number of forage and livestock producers are interested in alternative ways to provide fertility for forage systems without the use of commercial fertilizers. Possible alternatives that could be used in place of commercial fertilizer may include manure, poultry litter, compost, or biological amendments. Use of these alternative soil amendments may provide a more economical source of nutrients for forage and livestock producers, allowing them to continue to meet fertility needs to optimize forage growth.
Many of these soil amendments may also offer additional benefits beyond simply meeting fertility needs through improvements in soil health. Healthy soils will have greater soil organic matter, increased nutrient cycling in the soil, greater soil water holding capacity, and more soil biological activity (Collins et al., 2017). All of this translates to a more resilient soil, capable of withstanding stressors and supporting plant growth under a wide range of conditions. This aspect is important to producers as well; in the 2020 Maryland Forage Needs Assessment, the third-highest ranking topic of interest for producers was ‘improving soil organic matter’. Soil amendments like manure, poultry litter, and compost can help build soil health by providing a source of organic matter along with nutrients, and biological amendments often focus on improving soil biological activity. As a result, producers are interested in these products not only for the fertility they may provide, but also to help improve overall soil health.
Cooperators
- (Educator and Researcher)
- (Educator and Researcher)
- (Educator and Researcher)
Research
Treatments
The six soil amendment treatments that are being compared in this project include manure (uncomposted), poultry litter, compost, a biological amendment, commercial fertilizer, and a no-fertility control. These treatments were chosen because they are widely available, commonly used sources of fertility for forage systems in the Northeast region. Amendments will be applied starting in the spring of 2026 as replicated treatments under both grazing and hay production systems across two consecutive years at three sites (1 pasture, 2 hay production). All treatments will be applied to an established cool-season perennial stand containing species commonly grown in perennial pasture and hay systems across the Northeast region (e.g. orchardgrass, tall fescue, clover, alfalfa).
Methods
The experiment will be set up as a randomized complete block design with four blocks at each of the three sites (1 pasture, 2 hay production). Replicated plots for each treatment will be approximately 0.25 to 0.5 acres in size (total of 6 acres at each site for hay production system and 12 acres for pasture system), allowing for more of a full-scale comparison of the different treatments. Fertility treatments will be broadcast spread onto plots using either a box spreader (for manure, poultry litter, and compost), fertilizer spreader (for commercial fertilizer), or sprayer (for biological amendment). All spreaders will be calibrated to achieve the target application rates prior to use. All sites will be located at a University Research Center and the study will be conducted over multiple growing seasons to account for annual weather variability.
During year 1 (2025), forages were planted at both sites in the fall of 2025 to ensure sites are similar and consistent in terms of forage quality and quantity. Seeding rates were set based on existing recommendations for cool-season perennial stand establishment and all forages were established using a no-till drill. An existing, high-quality cool-season perennial pasture will be utilized for the pasture site. In the fall of 2025, soil samples were taken from each site to determine pre-treatment soil nutrient status and to complete a comprehensive soil health assessment prior to fertility applications. Soil microbial activity was also evaluated at each site using bait lamina strips to determine pre-treatment activity levels. Soil fertility for each site will be amended according to these soil analysis results to ensure equal soil pH and nutrient status prior to treatment applications. Moving forward, soil sampling and microbial activity testing will be repeated in the same manner on an annual basis.
The fertility experiment will take place during years 2 (2026) and 3 (2027). Fertility treatments will be applied in the spring of each year. Commercial fertilizer application rates will be based on initial soil test recommendations. Manure, poultry litter, compost, and biological amendment application rates will be based on published industry recommendations for each product. No fertility will be applied to control treatment areas.
For the hay production sites, forage will be harvested 4 times throughout the growing season to represent a four-cut hay harvest system. The first harvest will occur when forage reaches the boot stage of development (prior to seedhead emergence), with subsequent harvests taken at approximately 40-day intervals. Available forage will be mechanically harvested down to a 4-inch stubble height.
For the pasture site, a mixed-species livestock herd will be rotationally grazed within the pasture during the growing season. Approximately 20 stocker cattle and 30 lambs of similar age, weight, and body condition will be used; these species were chosen because they are commonly used on grass-based operations in the Northeast region. Livestock will be sourced from local producers, with all cattle coming from one farm and all lambs coming from one farm to ensure similar pre-study background and care. At the time of arrival, livestock will be acclimated to each other and to the research site. Livestock will rotate through the pasture based on forage availability and growth. Grazing will be initiated when the average sward height reaches at least 10-12 inches, and stocking days will be adjusted to leave a 4-5 inch stubble height. Each paddock will be set up so that livestock have access to all six treatments at a time in order to assess grazing preferences. Throughout the duration of the study, livestock will have ad libitum access to water and minerals to ensure all nutrient requirements are being met. If at any time pasture quantity or quality are insufficient to meet nutritional needs, dry hay will be supplemented as needed.
Data Collection
For the hay production system, forages from each treatment will be harvested mechanically using a flail-type forage harvester. At each harvest, forage biomass will be collected from two 3-foot by 20-foot strips from the center of each plot using a forage harvester set to a cutting height of 4 inches. Harvested forage will be weighed and dried in a forced-air oven at 60°C to allow for dry matter and forage yield calculations. Subsamples will be collected and sent to a commercial forage testing laboratory (Cumberland Valley Analytical, Waynesboro, PA) for analysis.
For the pasture system, forage samples from each treatment will be collected on a biweekly basis from the subsequent paddock in the rotation prior to grazing. Forage yield will be determined by hand-harvesting standing forage down to a 4-inch stubble height within a 2.8 ft2 quadrat at 6 random locations within each plot. Yield samples will be weighed and dried in a forced-air oven at 60°C to allow for dry matter and forage yield calculations. Forage quality samples will be collected by hand-clipping random samples from a minimum of 10 locations within each plot. Quality samples will be mixed to produce a single composite sample for each plot and sent to a commercial forage testing laboratory (Cumberland Valley Analytical, Waynesboro, PA) for analysis. Following grazing, post-grazing preferences will be estimated visually for each plot by trained observers to assess grazing selectivity.
For both pasture and hay systems, botanical composition will be assessed seasonally (spring, summer, fall) for each plot using a line intercept technique. Soil samples will be collected from each plot annually to determine soil nutrient status; samples will be sent to a commercial soil testing laboratory (Cornell Soil Health Lab; Ithaca, NY) for a comprehensive soil health assessment. Soil microbial activity will be evaluated annually for each plot using bait lamina strips to determine microbial activity levels. Economic data will also be measured for each treatment within each system, including total costs associated with treatment type and application.
Data Analysis and Presentation of Results
At the conclusion of the study, the collected data will be analyzed in terms of forage yield (tons per acre), forage quality (e.g., fiber, protein, energy), botanical composition, grazing preferences (for the pasture system), soil fertility (nutrient status), and soil health metrics (e.g., soil organic matter, water holding capacity, biological activity). In addition, an economic analysis will be completed to compare the inputs, outputs, and relative success for each fertility treatment.
All data will be analyzed as a mixed model analysis using SAS statistical software. Study results will be presented in several ways, including newsletter articles, Extension factsheets/reports, research updates at Extension meetings, and presentations at scientific conferences. The research team will also compile study results into a peer-reviewed publication which will be submitted after project completion.
Results for this project have not been collected yet, as year 1 (2025) was built into the project timeline to be a preparation year to get the research sites prepared, soil samples collected, etc. This preparation has been completed and we are on track to begin the actual experiment and data collection starting in 2026.
Education & outreach activities and participation summary
Participation summary:
The experiment is set to take place in years 2 and 3 of this project, during which time the project team will follow outreach plans as described in the study proposal. The research team is currently working on organizing the annual field day at the research site, which will occur during the summer 2026. The team is also working on recruiting potential producer farms interested in participating as on-farm demonstration sites. Once fertility treatments are applied and grazing/forage harvest begins in 2026, the team also plans to regularly share project updates via University of Maryland Extension channels and through partner networks.
That said, even though the experiment part of this project had not yet begun, the research team did host a field day at the study site during 2025 and information on this project and future plans for the project moving forward were shared with attendees.
Learning Outcomes
The experiment is set to take place in years 2 and 3 of this project, during which time the project team will follow outreach plans as described in the study proposal. Learning outcomes that occur as a result of this outreach will subsequently be documented and reported.
Project Outcomes
As the research team has prepared to being the experiment this coming year, several new working collaborations have already been developed connecting the original project team with new collaborators who are interested in this project and its outcomes. Moving forward, these collaborators will be working with the project team and participating in upcoming educational and outreach events.