After recent storms passed through the Lake Preston area, we walked the Lake Preston L.E.A.P. plot checking for green snap and root lodging. Green snap happens when strong winds cause the stalk to break, typically at a node. Green snap typically occurs when the stalk is rapidly elongating, resulting in brittle cell walls. This is typically between the V8 growth stage and tasseling. The stalk is taller, and the leaf surface area increases which makes it easier for the wind to catch the plant and break the stalk. All corn hybrids are at risk of green snap, but hybrids vary dramatically in their tolerance to green snap.
Other factors that influence green snap and its severity:
- Time of day of the storm and wind speed
- Growth stage of the corn during the wind event
Conditions prior to the storm, such as soil moisture and temperature
- Management practices that influence growth and development such as high N, P, and K rates; spring-applied N fertilizer, tillage, high organic matter, plant population, weed and pest management
- Field characteristics including topography, soil type, row spacing and row direction relative to the direction of the wind
- Herbicide interactions
Green snap will result in a yield loss. Breakage can occur above the ear node or below. If the break is below the ear node, there will be a greater yield loss than if the break is above the ear. The severity of the green snap will differ based on the timing of the wind event and the strength of the wind.
Some plants may not break and will have root lodging instead. Growers can calculate the yield loss from the percentage of plant breakage. The table below shows the correlation between the percentage of the stand being reduced and the expected yield loss. The more stalks that have snapped, the greater the yield loss. The best way to avoid green snap is to choose a hybrid that has a strong genetic background that has handled green snap in the past.
Red-Headed Flea Beetles
We also discovered red-headed flea beetles on some corn leaves. These beetles also feed on other plants such as soybeans and alfalfa. Red-headed flea beetles can be identified by their black shiny bodies and the red patch on their heads. Flea beetles have larger hind legs, so they are able to jump like fleas when disturbed. You can see the larger hind legs sticking out the sides of the beetle’s body in the first picture. You can also see in the picture below, the damage that red headed flea beetles can do to corn plants.
They feed on the leaves and cause a windowpane look, resulting in defoliation. These beetles can also feed on the silks of the ear and clip the silks. This can result in pollination problems if the feeding is severe. There are no treatment guidelines established for this pest, as it is considered rare. However, if defoliation is greater than 20% and plants are in the reproductive stages, it may be worth an insecticide application.
LEGEND ELITE ADVANCEMENT PROJECTLegend Elite Advancement Project (L.E.A.P.) is our proprietary, in-house research program. It validates data on hybrid genetic performance over time and agronomic placement. Our L.E.A.P. plots are used for product evaluation, selection, and positioning on the right soil type and in the right geography to consistently deliver high value products to growers. Since 2014, we've conducted 85,890 replicated corn trials across 68 locations. As a result of our rigorous testing, we advance only the elite hybrids into our line-up, averaging 19 new products per year out of the thousands we tested.