NC State Extension Official Variety Testing (OVT) Program

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The NC State Extension Official Variety Testing (OVT) Program is changing. The program is designed to measure the performance of corn, cotton, soybeans, tobacco, and wheat varieties. This data helps farmers choose varieties that are best suited for their fields.

Since the 1950’s the OVT crop yield data was published in booklets called the OVT Green Books. These books were replaced in 2015 with a website. Publishing the data to the web reduces costs and gives farmers access to the information in days rather than in months.

Ryan Heiniger leads the OVT program. He is a faculty member of NC State University’s Department of Crop and Soil Sciences. Choosing the right variety is one of the most important decisions a crop farmer has to make. It sets the stage for making the difference between profit or loss.


The OVT program is working with N.C. Cooperative Extension IT programmers to develop a database for the variety information. The database will allow growers to generate customized reports from the website. This report can be based on their location and other environmental variables that can affect yield. Farmers will be able to mine the variety data and select the best seeds for their fields. This dataset includes the research conducted at NC State University Research Stations as well as data from N.C. Cooperative Extension trials conducted at the county and regional level.

Incorporating data from research stations as well as county trials makes a very robust data set for farmers. Seed companies are very willing to be part of these variety trials. They like the variety testing design and have confidence in the unbiased testing from N.C. Cooperative Extension and NC State University.

Caldwell County participates in a regional corn variety trial with Davie, Iredell, Rowan, and Wilkes Counties. This is the Western Piedmont Regional Corn Variety trial. The trial consists of each county planting the same 16 varieties in local farm fields.

planting cornFarmers like the trials because it is local data. In Caldwell County Mike Willis has been the cooperating farmer. For the past two years, the Caldwell corn plots have been across from the United Presbyterian Church on Pennell Street in Lenoir. It takes extra time at planting and harvest to put in a trial, but being able to have good data makes it worth the effort.

The Caldwell Trial also receives harvest assistance from Boyd Glenn and Zeb Saunders.

Boyd and Zeb are Nutrien Ag Solutions store managers in Statesville and Yadkinville respectively. They supply a weigh wagon, and help with the harvest.

The weigh wagon is essential for measuring the harvest. Each strip or variety plot is 6 rows wide and 400 feet long. weigh wagonThe rows are 30 inches apart so each plot is 6,000 square feet. The combine harvests the plot then augers the corn into the weigh wagon. The corn is weighed in the wagon before augering it into the dump truck. Each plot is typically 1,200 to 2,000 pounds of corn. Without a weigh wagon it would be difficult to accurately weigh the yield.

A corn sample is also collected from each variety plot so we can measure the moisture content of the grain. sample closeup The plot yield is calculated form the percent moisture of the grain and the weight of the grain collected by the combine. A Google spreadsheet makes all this easy to calculate. Also, since we enter the data into the Google sheet right in the field, we can quickly get this information processed.

These changes to the OVT program are very exciting. Farmers and seed companies are part of the process to improve the entire OVT system. However, there is one thing that is not changing, and that is the continued commitment to provide unbiased variety performance data.