Understanding Relative MaturitiesApril 11, 2014 | Category: Agronomy |
The term “Relative Maturity” is often used when discussing corn and soybean seed. It is best defined as a criteria or process to compare or group hybrids and varieties based on physiological maturity. This is extremely important to understand when creating your cropping plans as you assign hybrids or varieties to your fields.
It is often questioned why different seed companies’ varieties of the same Crop Heat Unit (CHU) designation do not always mature at the same time. There are several factors that can distort the CHU system. Firstly, the CHU rankings are set by individual companies; there is no legal governance on how a product is classified, therefore it is only the opinions and beliefs of that seed company. Secondly, different seed companies use different formulas to rank their hybrids. Some choose to measure the CHU required for the hybrid to achieve black layer from planting date, while others use CHU from emergence to black layer. This can lead to some significant variances in rankings, as it often takes between 150 and 200 CHU for a corn seedling to emerge. Other factors that influence maturity are plant health, flowering date and environment.
A great management tool to minimize risk is to spread out the maturities of your crops. This will help minimize the environmental impact on your entire crop as different maturity groups are at different stages throughout the growing season.
Before heading to the field with the planter this spring, ensure that you understand how each of the hybrids and varieties being planted relate to each other in terms of maturity. It will help aid in comparing varieties, planning crop inputs (fertilizer, herbicides and fungicides), and help you prioritize fall harvest.
Cain Templeman, CCA-ON, Maizex Seeds Yield Specialist, Huron and Perth Counties