Project Overview
Commodities
- Agronomic: corn, soybeans
Practices
- Crop Production: conservation tillage, no-till
- Soil Management: soil quality/health
Proposal abstract:
Over the past 30 years, many corn and soybean growers in Pennsylvania transitioned from conventional tillage to reduced tillage and no-till systems, which reduce soil erosion and promote soil health. However, there are multiple management tradeoffs in long-term, no-till cropping systems. The need for effective crop residue management in no-till cropping systems has resulted in recent adoption of vertical tillage, which is primarily a residue management practice characterized by cutting, sizing and incorporation of crop residue within the top 5-10 cm of soil. Though vertical tillage use has become more widespread, there is little scientific information available to document crop production and soil conservation tradeoffs related to this practice. We propose to conduct replicated on-farm field trials over a two-year period to study the effects of vertical tillage on weed control performance, nutrient management, crop performance, and short-term indicators of soil health. Results from on-farm field trials will be communicated to agricultural professionals and the grower community through using several outreach mediums, including an extension newsletter article, an extension field day, and a winter workshop.
Project objectives from proposal:
On-farm strip trials will be utilized to contrast no tillage with vertical tillage conducted in the spring to manage corn residue in the transition to no-till soybean production. Our overall objective is to characterize and communicate production and conservation tradeoffs associated with vertical tillage practices using a multi-criteria assessment. Specific objectives include:
Objective 1. Evaluate vertical tillage effects on surface residue cover [i.e., soil erosion potential].
Hypothesis 1. We expect to measure greater than 60% surface residue cover in the no-till treatments and less than 60% surface residue cover in the vertical tillage treatments.
Objective 2: Evaluate vertical tillage effects on weed management outcomes by measuring (a) pre-plant winter annual weed control, (b) summer annual weed emergence timing [i.e., false-seedbed potential], and (c) soil-applied residual herbicide efficacy.
Hypotheses 2: Relative to no-tillage, vertical tillage will (a) reduce density of established winter annual weed species, (b) increase recruitment of early-emerging summer annual weed species due to stimulation of disturbance-related germination cues, and (c) increase soil-applied residual herbicide efficacy due to reduced herbicide interception and adsorption of crop residues. We anticipate the magnitude of vertical tillage effects on weed control will vary considerably across locations but be partially explained by the difference in surface residue incorporation within each location.
Objective 3: Evaluate vertical tillage effects on crop performance metrics, including (a) crop emergence, and (b) crop yield.
Hypotheses 3: Relative to no-tillage, vertical tillage treatments will result in (a) more uniform soybean plant emergence and early season vigor and (b) higher crop yields.
Objective 4. Evaluate vertical tillage effects on selective nutrient management factors, including (a) pH stratification, and (b) P stratification [i.e., nutrient loss potential] across the soil profile [0-5 cm, 5-10 cm, 10-15 cm, and 15-20 cm depths].
Hypotheses 4: Relative to no-tillage, soil within vertical tillage treatments will be characterized by (a) higher pH and (b) lower soil test P levels at shallower soil depths.
Objective 5. Evaluate vertical tillage effects on short-term soil health indicators, including (a) soil organic C stratification, (b) soil penetration resistance [i.e., compaction alleviation], and (c) soil bulk density.
Hypotheses 5: Relative to no-tillage, vertical tillage will result in (a) decreased soil organic C stratification due to greater soil mixing of crop residue; (b) higher soil penetration resistance below the operating depth of the vertical tillage tools, and (c) lower soil bulk density at shallower soil depths.