Plant height has been shown to be positively correlated with both yield and lodging. Soybeans can get too tall and lodge. Yet if soybeans are too short, the pods are closer to the ground and harder to retrieve with a platform head.
Lodging in soybeans can be an issue and soybean contest winners often deal with tall and rank beans that lodge, decreasing yield (up to 10%) and profitability. Lodging that happens before R2 (full flowering) doesn’t significantly impact yield because soybean branches take on main stem pod-bearing characteristics. However, lodging that occurs from R3 (beginning pod) to R5 (beginning seed) can significantly impact yield. Lodging during R6 and R7 primarily impacts harvestability.
Lodging is common a risk in high-yield scenarios and there are two main factors that contribute to lodging: variety and environment.
Variety is characterized by height and bushiness. Taller plants are more susceptible to lodging and lodging ratings give an indication of standability. If you are planting in a high-yield environment using good management practices and have a history of lodging, select a variety that is shorter. In contrast, in a lower-yielding environment or on timber soils plant a taller variety. Lodging will, based on the severity, reduce yield and make harvest more difficult.
Higher-yielding environments generally promote taller, more robust plants which are more susceptible to lodging. So planting a high-yielding racehorse variety on a deep, loamy soil with high fertility, using the best management practices, and having a cooler and wetter summer than average mean plants can get too tall and lodge.
And plant population plays a role. Overplanting, especially when drilling, can cause plants to lodge because plants grow taller and more slender as they compete for light.
So what are some of the strategies to reduce risk of plants getting too tall and lodging?
- Planting early can avoid warmer temperatures during the vegetative stage of growth, decreasing height and reducing lodging risk while increasing yield potential.
- Plant higher-yielding race horse varieties in more lodging-prone, high-yield fields first.
- Plant at 125,000 to 150,000 seeds per acre. Higher populations can promote lodging without increasing yield.
- Lodging can and does happen at times, so consider using a draper to be able to harvest more pods lower to the soil surface.
If lodging is a risk include strategies such as early planting, variety selection and reduced seeding rates.
Agronomist Dr. Daniel Davidson posts blogs on agronomy-related topics. Feel free to contact him at djdavidson@agwrite.com.