Evaluating the efficacy of multiple foliar sprays for soil health, pasture quality, and cow productivity

All farmers need to figure out a labor and cost effective way to return nutrients to the soil. Grass­based livestock farmers typically use such large tracts of land that foliar spraying is an efficient method for applying nutrients to the soil. There are many products available that are extolled for this very purpose. Some of these products can be produced on the farm (such as compost tea), some are byproducts (such as whey), and some are commercially sold products (such as Neptune’s Harvest). The commercially available products come with significant claims for increase in soil health and forage yields, however there is limited scientific on­farm research that validates these claims. Some of the non­commercial products, such as compost tea and raw milk have been widely popularized but are also lacking in substantiating data from replicable research. This creates a muddy maze of products for farmers to wade through if they are interested in amending their pastures or hayfields. It is risky and expensive to trial foliar sprays. Our project will trial 6 different spray treatments on our pastures and hayfields in order to help mitigate that risk for others. We will measure 9 different variables as indicators for soil and plant health. As a two-year study we will have the depth and breadth to provide a clear and thorough analysis of the comparison of different foliar spray treatments in the setting of a grass­based livestock farm. 

There are two organizations that we already have close ties to, where we will submit reports of our research - NOFA/Mass (monthly newsletter read by over 6,000 people) and the Beginning Farmer Network of Massachusetts.  We will also submit our report to the regional publication The Natural Farmer which is sent to 5,000 households on a quarterly basis.  Additionally, we hope to publish articles in online resources such as the Northeast Organic Dairy Producers Alliance and other similar forums where farmers discuss practices.  

Three regional conferences where we hope to share our findings are The National Young Farmers Conference at the Stone Barns Center for Food and Agriculture, the NOFA/Mass conference at Worcester State University, and the NOFA Summer Conference at the University of Massachusetts at Amherst. We also hope to present at the Winter Green-Up Grass-Fed annual conference organized by Cornell University Cooperative Extension of Albany County.  

With regards to trainings, we plan to train farmers, extension agents, and consultants through field days and on-farm workshops.  We are planning to work with local organizations that we have partnered with in the past such as Berkshire Grown, NOFA, and Cornell University Extension to host pasture walks and field days on our farm.  Finally, we will also contact our local media outlets.  We are also optimistic that our local papers will pick up the story, as they also often feature stories about us or other regional farms.  Through these publications, workshops, and trainings we will reach hundreds of farmers in our region as well as dozens of extension agents and agricultural consultants.  

This project will accomplish the objective of determining what the most effective foliar feeds are

for improving farm nutrient cycling as indicated by soil health, forage quality & quantity, and cow health. We will trial 6 different foliar sprays on both our pasture and hay land. We will then measure 9 different variables that we have identified to be indicators of nutrient cycling over the span of two years.

We will carry out our research in three areas: the main dairy pasture, secondary dairy pasture, and hay fields. The main dairy pasture is a 22.8 acre plot that is divided into 15 paddocks of roughly equal size ­ 1 1⁄4 acres each. We will exclude one paddock from the research because it was plowed last fall as part of another research project evaluating a management technique for controlling Tall Fescue. This leaves us with 14 paddocks in the dairy pasture to use for the experiment. We will have six treatment groups (paddocks) of different foliar sprays and one control replicated twice over the 14 paddocks.

For the hay fields we will use three separate fields, with all three of them divided into two treatments. We will use a 5.7 acre field “the Sweet Piece”, a 17.2 acre parcel called “the 30 Acre Piece” and a 16.7 acre parcel called “the 40 Acre Piece”. Clearly the hay field names are legacies of the past before hedgerows and woodlands encroached.

The six treatments that we will use for foliar spraying the dairy paddocks are: (1) raw whole milk, (2) raw skim milk, (3) whey (a by­product of our cheese making operation), (4) Neptune’s Harvest Fish Emulsion, (5) homemade vermicompost tea, and (6) a blend of two products produced by Advancing EcoAgriculture called PhotoMag and MicroPak. The dairy paddocks will receive three treatments each year for two years. The first treatment will be in the first week of May, the second will be in the first week of July, and the third will be in the first week of September. The work of spraying will be done by Topher Sabot, Suzy Konecky, and possibly one of the farm apprentices. We expect each spray treatment to take 1 hour on average; driving out to the farther hayfields will add additional time.

Vermicompost tea was chosen because unlike regular compost, vermicompost does not have to be turned. The worms turn the organic matter by digesting it. We understand the challenges of brewing compost tea, and have some experience with it from a previous management position at Cornell University’s student organic farm. We are not currently brewing compost tea here at the farm, but we will create a system over the winter to allow time to become proficient before application starts in the spring.

The secondary dairy pasture is a 6.5 acre plot that will be treated with one single treatment so that we have an area where the cows stay long enough to see variations in standard milk metrics (components and volume). It will be sprayed only with the PhotoMag and MicroPak blend.

The Sweet Piece will be treated with the PhotoMag and MicroPak on one half, and whey on the other half, the 40 Acre Piece will be treated with the vermicompost tea and the fish emulsion and the 30 Acre Piece will be treated with whole raw milk and also contain a control plot. The skim milk and whey treatment will be excluded from the hay field plots. The hay fields will be sprayed at three points throughout the season — first when they are emerging from dormancy, second immediately following the first cut of hay, and third immediately following the second cut of hay.

Our application rates will vary based on the foliar feed and what the recommended rates are for each product (either given by the company or the amount used successfully in previous research). We will spray raw milk and whey at a rate of 3 gallons of milk diluted with 17 gallons of water on both the pastures and the hay fields. Gompert and Wetzel found no difference between the 3, 5, 10, and 20­gallon application rates in their on­farm trials.

We will apply Neptune’s harvest slightly differently to the pasture versus the hay fields, so that we are following the recommended application rates as prescribed by the company. For the pasture we will spray at a rate of 3 gallons of fish x 30 gallons of water per acre. For the hay fields we will spray 2 gallons of fish x 20 gallons of water.

Recommended compost tea rates vary considerably depending on the source. The 2005 SARE grant referenced above used compost tea at a rate of 20 gallons per acre but suggested possibly a higher rate for future research. However, the University of Minnesota extension recommends applying VCT at a rate of 5 gallons per 1,000 square feet which equates to a rate of 217 gallons per acre. It is not logistically feasible for us to spray the hay fields at the higher rate due to limitations in equipment and infrastructure. Therefore, we will spray the pasture at the higher rate of 217 gallons per acre, following the recommendation of the University of Minnesota and the hay field at a lower rate of 35 gallons per acre, the most that we can fit in our sprayer at one time.

We will spray PhotoMag and MicroPak at a rate of a rate of 2 gallons per acre (1.5 gallons of PhotoMag and 0.5 gallons of MicroPak), which is the rate recommended by Advancing EcoAgriculture.

We will evaluate the efficacy of each spray protocol based on the variables we have identified as the clearest and most through indications of soil and plant health. These variables, and our full sampling protocol, is explained in detail in the following question.