Impact of using high-quality biological compost and compost extract on corn production, plant nutrient content, and soil quality

Impact of using high-quality biological compost and compost extract on corn production, plant nutrient content, and soil quality

Summary

With partnering farmer Dan Hunsicker, a corn grower in Pennsylvania, we conducted a research study to demonstrate whether the addition of an organic amendment in conjunction with standard cropping practice (continuous corn-conventional system) would lead to better soil health and improve corn plant and kernel production and weed management. The organic treatments included applications of compost extract, and high quality compost with and without compost extract. These treatments were compared with the standard grower’s practice (synthetic fertilizer and herbicides). Compost was applied three weeks before planting and compost extract was applied at planting, and one- and two- months after planting. Weed biomass and soil samples were collected periodically for chemical and biological assessment from each treatment in four replications. Whole plants and corn ears were harvested from 10 linear feet of each plot to determine plant biomass, corn ear and kernel yield.

Preliminary results showed that soil bulk density was reduced from 1.45 g (standard practice) to 1.35 g per cubic cm (compost + extract). While corn whole plant biomass was highest in the standard treatment, followed by the compost treatment, corn ear yield was highest in compost-amended treatment and similar to extract treatment, followed by compost + extract and least in standard practice.

We trained seven interns on soil and plant sampling and processing, and three technicians were involved in extract preparation and application, and processing weed biomass. We shared project information with approximately 100 people who attended our annual on-farm field day on July 19, 2013 at the Rodale Institute research farm in Kutztown, Pennsylvania.

In the next two quarters, we will determine kernel yield and compile data on soil chemical and biological content, post a web article, and present project data results to growers and the scientific community at upcoming conferences. A manuscript will be prepared on the impact of the treatments on soil and plant productivity.

Objectives/Performance Targets

We were very successful in accomplishing the goals of the project this year. We have been in contact with our partner grower, Dan Hunsicker, from initial project planning through the fall 2013 harvest. Mr. Hunsicker was very pleased with our coordination of project activities and he has been a great communicator, assisting us in completing tasks timely.

In brief, together we:

• Laid out the project design in the field, four treatments with four replications; each plot size was 40 feet by 40 feet.
• Applied a prepared high-quality compost at 1 ton per acre three weeks before planting on plots that received compost treatment.
• Prepared compost extract at Rodale Institute and assessed for biology prior to providing to Dan Hunsicker at time of planting.
• Periodically applied compost extracts using a back pack sprayer, sampled soil and plant material, and assessed biology and chemistry of compost, compost extracts, and soils.
• Trained seven interns on assessing compost and compost extracts under the microscope for biological organisms and application of compost extracts using back pack sprayer.
• Shared project information with approximately 100 people who attended our annual on-farm field day at the Rodale Institute research farm on July 19, 2013.
• Hand-harvested whole plants and ears from 10-foot linear rows per plot to assess impact of treatments.
• Harvested corn using Dan Hunsicker’s combine machine to compare with hand-harvested corn kernel yield.

Accomplishments/Milestones

In coordination with the grower, we flagged the field where the treatments were applied, and sampled soil and weeds on March 28 and April 4, respectively. High-quality compost was assessed for biology and applied at 1 ton per acre on April 11. Dan Hunsicker contacted us and scheduled a corn planting date on May 3. Compost extracts were prepared and provided to the grower on the day of planting. Second and third compost extract applications were done one month and two months after planting (June and July 2013). Before applications of compost extracts, soil samples were collected for chemical and biological assessment.

We improved our hand-harvest method by using a definite row size (10-foot linear length) and counted the number of plants and ears from the middle two rows per plot. We harvested whole plants in 10-foot linear lengths and took fresh and dry biomass weights. For nutrient content analysis, we selected six whole plants out of total number of plants, chipped and ground. We will thresh the ears and determine cob-to-kernel weights per treatment.

In 2013, we had many interns who were very interested in learning about the steps required to ensure correct preparation and application of compost extracts, assessing biological quality of compost and compost extracts using the shadowing method under the microscope, and soil and plant sampling and processing. In addition to the three part-time technicians who were involved in this project, we have trained seven other interns.

We shared project information with approximately 100 people who attended our annual on-farm field day on July 19, 2013 at the Rodale Institute research farm in Kutztown, Pennsylvania.

Based on project work during the period, we learned that, when having many interns and technicians involved in the project and interested in using back pack sprayer for compost extract application, it is necessary to train the technicians prior to time of application by pacing out the rows, pumping out the correct amount of water per area and monitoring the extract application rate. The interns all have received the same training – each individual was trained on using the microscope and pumping compost extracts they prepared, on 10 foot by 10 foot size plots, dedicated for their practice, at Rodale Institute.

• Photo 4-Hand Harvesting
• Photo 3-Counting Corn Plants
• Photo 5-Combine Harvesting
• Photo 6-Plants Ready for Harvest
• Photo 7-Corn Kernels
• Photo 1-Compost Extract Preparation
• Photo 2-Spraying Compost Extract

Impacts and Contributions/Outcomes

Our project goals were accomplished according to the work plan set with our grower partner – Dan Hunsicker. Both parties were pleased with the coordination of activities during the project period. Preliminary results showed that within one growing season, soil bulk density was reduced from 1.45 g (standard practice) to 1.35 g per cubic cm (compost + extract).

While corn whole plant biomass was highest in the standard treatment, followed by the compost treatment, corn-ear yield was highest in compost-amended treatment and similar to that in the extract treatment followed by compost + extract, and least in standard practice. So far, we expect to see positive impact of using high organic amendments on soil quality, plant nutrients and kernel yield.

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