The goal of the Pennsylvania Subsurface Application of Manure (SAM) Initiative was to reduce the loss of manure nitrogen (N) and phosphorus (P) to the Susquehanna River Basin, and ammonia-N to the atmosphere, by expanding the adoption of manure injection on farms in South Central, Pennsylvania.

The project demonstrated how trusted ag-service providers are uniquely positioned to expand conservation practice adoption. Our manure injection partner, Agri-Applicators, Inc., a custom manure application service owned by Jeff Zimmerman, invested in manure injection equipment and engaged 51 farmers injecting over the life of the project. With outreach and education support from Penn State researchers and Extension, the partnership expanded during the project timeframe to include groups like the PA 4R Alliance, the Maryland and Virginia Milk Producers Cooperative, and the Alliance for the Chesapeake Bay, who are uniquely posited to continue efforts to expand adoption of manure injection in PA.

Because of the success of this project, our partners secured additional funding to implement manure injection ($300,000 Campbell Foundation commitment to the Lancaster County Conservation District) and to document financial benefits of injecting anaerobically digested manure ($75,000 PA Conservation Innovation Grant). Additionally, manure injection was included in two recent Regional Conservation Partnership Program awards as an innovation worthy of expanded adoption.

As a result of this project, custom manure applicators, farmers and conservation partners are better informed about manure injection and demand for the practice is growing. At the start of our project in 2015, only three custom manure applicators offered manure injections services in Pennsylvania. Now, there are eleven custom applicators and at least 3 farmers injecting manure.


Our goal is for manure injection to be the norm.

— Jeff Zimmerman, Owner, Agri-Applicators, Inc.

Farmers participating


Acres of manure injected, annually


Pounds of nitrogen reduced, annually


Pounds of phosphorus reduced, annually


Custom applicators offering manure injections services in PA


Farmers reached

After one year of the project, Jeff Zimmerman (owner of Agri-Applicators, Inc.) traveled to Washington, Iowa with his wife and three daughters to tour manure injection equipment manufacturers.  He is now  a dealer for Bazooka-Farmstar manure injection equipment. He has since sold manure injection tool bars to at least 6 custom manure applicators and 3 farmers in the region.

Agri-Applications, Inc. uses a Bazooka Farmstar manure injection toolbar with a drag hose system to inject manure on a farm field in South Central, Pennsylvania.


We are also excited to report that ELS Manufacturing, an Amish equipment dealer has developed a horse-drawn, drag hose manure injection system suitable for use on Amish farms. The system utilizes a Bazooka Farmstar drag hose tool bar (purchased from Agri-Applicators, Inc.) and is pulled by a team of eight draft horses.  As far as we know, this is the first horse-drawn manure injection unit ever developed.

A drag hose manure injection system developed by ELS Manufacturing pulled by a team of eight draft horses at a Field Day event hosted by ELS Manufacturing, the Lancaster County Conservation District and the Campbell Foundation on July 15, 2021.

The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S Government, or the National Fish and Wildlife Foundation and its funding sources.