crop production and physiology
Stand Reduction: National Crop Insurance Services (NCIS) has conducted research for hail adjusting loss instructions for corn that include assessing losses from stand reduction/loss, defoliation, direct damage to stems and ears, etc. Past stand reduction research has led to the development of two loss tables for stand reduction/losses. One applies to stand reduction up through the 10th leaf stage (approx.
Previous research conducted at Purdue University at beginning flowering and pod set growth stages updated defoliation loss tables for current variety genetics, management practices, and climate. However, it also brought into question the defoliation loss tables for later reproductive stage soybean. This project occured in Iowa and Indiana (Shaun Casteel). Defoliation events were timed at full pod set (R4) and beginning seed fill (R5) reproductive stages.
The goal of this project is to positively change the skill sets and attitudes of professional agronomists, farmers and agricultural students to accelerate the adoption of agricultural systems that build soil health and reduce nutrient losses.
This project seeks to reevaluate the traditional “field edge,” investigating the long-term productivity and profitability of in-field low lying depressional areas. While traditionally planted to agricultural row crops, in the majority of years these marginal areas require significant inputs resulting in only modest crop yields and returns on investment. Can these marginal land areas be taken out of row crop production and transitioned to perennial vegetation to increase the return on investment with fewer acres and less risk?
Issue: The Iowa Nutrient Reduction Strategy (INRS) calls for cover crop implementation on over 12 million acres, which equates to every other field. Despite numerous environmental benefits associated with cover crops, many farmers are still hesitant to change their current production practices. Major barriers to introducing cover crops as a conservation practice include cost of implementation, yield drag, and knowledge.
Issue: Cover crops are a conservation practice that can have tremendous benefits for improving soil health and reducing nutrient losses. There is limited research available on management practices that provide farmers information to facilitate cover crop adoption and minimize potential yield limiting factors.
The purpose of this study is to evaluate different methodologies for developing variable rate seeding prescriptions in corn. Three prescription methods will be evaluated on yield and economics compared to a farmer chosen uniform rate. The three variable rate methods are normalized yield, topographic wetness index, and Corn Suitability Rating. This will be conducted in central Iowa in 2018 and 2019.