Early Stand Evaluation – Corn

Evaluating stand establishment can be a pretty quick and easy task, and is best done after all of the plants have emerged but while the crop is still very young. Here are a few suggestions on what to look for when evaluating stand establishment in your fields.

While one can get an impression of how well a field has emerged from the pickup window, a quality assessment can only be accomplished by doing a bit of walking. Walk at least twenty paces straight into the field before starting the evaluation, and then, once into the field that distance, shift from walking in a straight line to walking in a big circle. Walking in a circle causes a view across the rows, and looking across the rows makes it much easier to see differences among plants. Walking in a circle also focuses attention on more rows, resulting in a more complete view of the crop. Try to make the circle at least 24 rows wide, more if the planter is wider, and remember that viewing more rows will always improve accuracy of the evaluation. While walking across the rows, scan the row three rows ahead, specifically focusing on sections of row containing six to eight plants. Constantly shift from one set of six to eight plants to the next set of six to eight plants while making the circle.

The first thing to consider is emergence. Evaluate emergence by looking at the average distance between plants, and by tracking the number of skips, or blank areas in the row where a plant should have been but is missing. Skips that are followed or proceeded by a multiple seed drop are usually due to the planter and not the ability of the seed product to establish a stand. Consistent spacing between plants combined with a minimal number of skips indicates good emergence. If there appears to be a considerable number of skips and/or the distance between plants is not very consistent, consider taking a stand count to determine exact population, and therefore percent emergence. (See Rob-See-Co Agronomy Tips Taking Stand Counts – Corn, April 2015)

Next, check crop growth stage and, even more important, how uniform the plants are for that growth stage. To determine growth stage, look at the average number of leaves on the plants. Half leaf stages are encouraged in order to capture differences in growth rate, especially during earliest stages of development. Check uniformity by considering how similar the plants are in growth stage, plant height, and leaf size. A majority of the plants showing the same number of leaves and being similar in plant height and leaf size is desirable.

How well a field emerges and how strongly it establishes sets the stage for the entire growing season. Make time to do a thorough evaluation of stand establishment in every field.