Using a Kreger Farms Invented Interseeder to Profitably Plant Cover Crops into Varying Corn Growth Stages

Progress report for FNE20-956

Project Type: Farmer
Funds awarded in 2020: $7,859.00
Projected End Date: 06/30/2022
Grant Recipient: Kreger Farms
Region: Northeast
State: Pennsylvania
Project Leader:
Heidi Kreger
Kreger Farms
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Project Information


Cover or double cropping in northern, mountainous regions of Pennsylvania is not widely practiced, and it puts area farmers at an economic disadvantage as compared to their peers with more favorable crop growing conditions.  Unanswered questions and equipment unavailability make it tough for Northern farmers to profitably adopt cover cropping on corn grain and silage acres.

This project addressed if a Kreger Farms styled interseeder would profitably plant cover crops into standing corn. We varied what corn stage interseeding into succeeded, and what mixtures worked best. The interseeder went over reproductive corn (with very little damage) using seed mixtures of cereal rye, triticale, ryegrass, radish, and black oats. The triticale/tillage radish mixture (2020 planting) provided additional high quality forage in 2021, while the black oat/tillage radish mixture provided an excellent manure hauling location in wet weather in our bi-weekly manure hauling system. 

The Kreger Farms styled interseeder has been seen in FARM SHOW magazine,  even being the first story in their The Best of FARM SHOW 2021 Edition. It will also have a spot in the Farm Innovation Show at the PASA Sustainable Agriculture 2022 conference. 

Project Objectives:

The question we will answer is “Can broadcast interseeding using an inexpensive Kreger Farms interseeder be done successfully? Success is determined by percent cover after harvest and at spring time, and minimal yield loss. We want to know what cover crop species in what planting conditions will survive being broadcast into a corn canopy, have harvesting equipment stress it, and contribute to the field’s cover crop goals. We want to be able to make recommendations to other farmers with similar growing challenges as to what species to plant, under what conditions to plant, using a Kreger Farms styled interseeder. If this project is successful, more farmers will adopt or be able to borrow, a Kreger Farms styled interseeder to maximize their cover crops usage, and their overall land. More farmers would be able to enjoy the benefits of nutrient recycling, soil conservation, soil resiliency, a cheap and high clearance machine to increase their soil productivity and farm cash flow.


Successful cover cropping is a necessity for farms to reduce their environmental footprint and be profitable. Many northern Pennsylvania areas have shorter growing seasons than areas where cover cropping is widely researched. This experiment will be conducted at approximately 1800 feet elevation in contrast to the Ithaca area at 400 feet elevation and State College area of 1200 feet.    

Many times corn silage in Northern Pennsylvania is harvested well into October, making proper cover crop establishment after harvest difficult to achieve. Cover cropping on grain corn after harvest is not realistic. Cover cropping provides many observable benefits to producers. Successful cover crop establishment adds extra forage, retains fertilizer nutrients that would ordinarily be lost and improves soil structure to better handle water challenges farmers are facing more and more of.

If farmers in our county could improve their cover crop establishment, we could reduce soil loss, increase nutrient recycling and retention, and increase water holding capacity for only the cost of cover crop seed. These benefits make our farm more sustainable by increasing cash flow potential and reducing fertilizer dollars lost, along with making our soils more productive and resilient.

This farmer driven research project is aimed at northeastern farms in higher elevations with poorer soils when compared with typical research sites in Pennsylvania and New York.

When Kreger Farms started refurbishing the JD 6000 sprayer into an interseeder, six local farmers expressed interest in using the machine, the local extension agents offered to help calibrate the machine, FarmShow Magazine featured our interseeder in their February 2020 edition, and the two local conservation districts have expressed interest in a field day on our trial acres. Also, NRCS personnel are familiar with the machine and express a need for timely cover crop planting in this area.

The Kreger Farms developed interseeder was very cheap and simple to make. It cost a total of four thousand dollars and took approximately two days to build. Being inexpensive means more farmers can make their own interseeder and have increased access to a machine that can plant cover crop as the farmer’s time or budget allows, because this interseeder can go over mature corn. This allows farmers to plant field by field, crop by crop, and on varying time schedules. Being able to plant in mature corn allows a farm greater planting options. If a farmer does not have time at V5- V7 stage, the machine can still go over mature corn and cover crop can still be seeded before harvest. The Kreger Farms interseeder uses a spin spreader that can cover twelve rows (30 inch corn rows). Having planting flexibility also allows a farm to reduce any herbicide or nitrogen injury to cover crops.

The impact of maximizing a farm’s nutrient recycling, and soil resiliency, contribute to increased cash crop and cover crop productivity, and farm cash flow.


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  • Casey Guindon


Materials and methods:

We plan to conduct this research experiment in Morris, PA. The Kreger Farms designed interseeder will plant the cover crop seed. Zach Kreger (farm manager) will be the driver and oversee seed mixing. Cover crop seed will come from the Local Seeds Facility in Jersey Shore PA. Kreger Farms has their own seed mixing equipment and scales. The radish used was Local Seeds tillage radish. 

Planting cover crop seed will be done as follows:

V6 Interseedings                                                                                                                                            

  1. 100 lb/acre Cereal rye and 5 lb/acre radish in corn grain and corn silage.
  2. 25 lb/acre Annual ryegrass and 5 lb/acre radish in corn grain and corn silage.

V12 Interseedings                                                                                                                                          

  1. 92 lb/acre Cereal rye and 8 lb/acre radish in corn grain.
  2. 25 lb/acre Annual ryegrass and 5 lb/acre radish in corn grain.
  3. 92 lb/ acre Triticale and 8 lb/acre radish

Reproductive Interseedings                                                                                                                                                    

  1. 92 lb/acre Black Oats and 8 lb/acre radish in corn silage.
  2. 100 lb/acre wheat and 5 lb/acre radish in corn silage and corn grain.

Interseeded acres will total 100 depending on corn planting conditions and final crop rotation decisions.

Monthly height and dry matter estimations were taken by Heidi Kreger. A USDA Pasture ruler was used to measure height and dry matter. Pictures  documented  both. 

We will conduct corn tissue sampling between tasseling and silking. By this time nitrogen will be sidedressed and corn will be nearing the end of its nitrogen uptake. We can compare the tissue sample results to what fertilizer was applied and see what may be available for the cover crop.

Corn yield comparisons will be done. Silage will be measured in tons. The forage wagons are already calibrated and each field yield is normally analyzed.

Research results and discussion:

2020 progress:
     Progress and data NESARE update Jan2021
     Video of interseeded field

2021 progress: NESARE 2021 update

Four interseeded fields, and one control drilled field are used in the 2021 data. 2021 Growing conditions were opposite of 2020.  July, August and September saw 8.3, 6.29, and 6.87 inches of rain, respectively. The heavy clay soils took many days to dry out. Rain and sunlight are somewhat inversely related. 2021 had about 5,000 less Langleys of sunlight than the 2020 growing season (using the closest weather montoring station with complete sunlight data, Hegins, PA). Rain also brought another issue for farmers trying to interseed: time. The few sunny, drier, plantable days are filled with the routine, cash crop activites.  Consequently we were not able to conduct corn tissue sampling. 

Field 1 (HM5) : Interseeded August 11 with 92 lb rye and 8 lb radish. Growth was inconsistent across the field. A 100 foot swath, with tile drainage, had 60% cover. Everywhere else was bare. Rye seed even sprouted on the corn plant. 

Field 2 (HM1) : Interseeded August 15 with 92 lb triticale and 8 lb radish. Triticale grew to 10 inches tall, while the radish grew to about 6 inches above ground and 5 inches below ground. Dry matter estimation was 80% by the end of the season. 

Field 3 (HM3): Interseeded September 8 with 92 lb Black Oats and 8 lb radish. This field had the greatest cover and height. The Black Oats were 12 inches tall by the end of the season, and dry matter estimation was 100%. Kreger Farms has a semi-weekly manure haul. During muddy conditions in late fall 2021, we were able to spread 4000 gallons of dairy slurry without tracking up the field. 

Field 4 (Willis 4): Interseeded September 16 with 92 lb wheat and 8 lb radish. The wheat grew to about 3 inches tall, radish was about the same. Dry matter estimation was 50%. This is a very wet field, but Zach thought it planted well. For our purposes, we were disappointed with it. 

Control field (W. Triangle): Drilled 92 lb wheat and 8 lb radish September 18 after corn was chopped.  The wheat grew to 8 inches tall and 90% dry matter estimation. This field is directly above field 4 on a hill. It had tremendously better growth, and we are hopeful we can use it as a wheat field in 2022.

Participation Summary
2 Farmers participating in research

Learning Outcomes

3 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
Key areas in which farmers reported changes in knowledge, attitude, skills and/or awareness:

Knowledge: Interseeding (even general cover cropping) is a dynamic crop strategy that requires continual evaluation.  What works under certain conditions may not work the next year under slightly different conditions. You cannot be afraid to fail.

When conditions are not extreme, interseeding works excellent. When they are extreme, "The Plan" requires background knowledge of the fields (soil type, water flow, organic matter content, etc.) and a thorough understanding of the cover crop being planted (amount of sunlight required to germinate, hydrophobic verses hydrophilic root systems, etc.)

 Interseeding may also require some additional fertilizer. Kevin Brown, Bradford County Conservation District technician, has discussed with us there are 2 crops growing at the same time. In wet conditions, is there anything left for the cover crop to thrive on? What about decaying organic matter nutrients that are slowly available throughout the growing season?

Project Outcomes

1 Farmers changed or adopted a practice
Project outcomes:

Kreger Farms will continue to interseed and experiment with different mixtures. We have had promising results from improved water infiltration and increased soil organic matter, up to 8%. 

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 or SARE.