The Effect of Dairy Manure and Inorganic Nitrogen on Soil Fertility, Nutrient Uptake and Yield in Corn.

The Effect of Dairy Manure and Inorganic Nitrogen on Soil Fertility, Nutrient Uptake and Yield in Corn

Authors: Melissa Preston and Dr. Natasha Macnack

University of Wisconsin-River Falls

Previous research has shown that the application of manure has beneficial effects to the soil and can increase corn yields. The research that will be conducted will evaluate soil organic matter, pH, macro nutrients, micro nutrients, cation exchange capacity, bulk density, and microbial activity in a soil to which manure has been applied and compare these same parameters to a soil where inorganic fertilizer has been applied. One objective of this research is to compare the soil health and soil fertility benefits when using dairy manure versus inorganic nitrogen (N) fertilizer. Another objective is to compare the effects on nitrogen uptake and corn yields. There will be four treatments replicated three times and arranged in a randomized complete block design. This field study will be conducted at University of Wisconsin-River Falls’ Mann Valley Farm. Treatments will include a control block with no manure or inorganic fertilizer. Two treatments will have dairy manure, one will have 30 tons per acre, and the other will have 60 tons per acre. The last treatment will have 150 pounds of nitrogen per acre (170 kg per hectare). For treatment four, urea (46-0-0) fertilizer will be used for the nitrogen source. Throughout the study, plant height will be taken at different growth stages to help determine effects on corn yields. Biomass will also be taken at growth stages V5, V8, V10, V12 by using a GreenSeeker. Samples of soil will be taken before planting, mid-season, and after harvest. Results will show that application of manure resulted in higher microbial activity in soil and improved soil fertility.