There are several reasons growers have questions related to harvesting soybeans early. Cover crop establishment is one of the reasons and the initial purpose for conducting this project. Other reasons include tile projects, manure management, early soybean contracts or simply an early start on harvest.
To investigate two methods of achieving early soybean harvest. The first is using ultra early soybean varieties for a given geography and second using desiccation of soybean in the late R7 and early R8 stage of development using herbicides. We will then evaluate yield performance and economic returns for this system.
- 15” rows planted as early as soils were ready at 150,000 seeds per acre
- 10’ wide plots – 8 rows
- DSR-3058E™ and paraquat herbicide at R7
- DSR-3587E™ and paraquat herbicide at R7
- DSR-3058E™ and paraquat herbicide at R8
- DSR-3587E™ and paraquat herbicide at R8
|Treatment||Avg Yield||Spray Date||Harvest Date|
|DSR-3058E at R7||53.5||9/13||9/22|
|DSR-3058E at R8||60.2||9/15||10/6|
|DSR-3587E at R7||57.9||9/17||10/6|
|DSR-3587E at R8||59.8||9/20||6-Oct|
Recommendations from this study really come down to personal preference from the producer standpoint. There are obvious yield penalties for certain early soybean harvest strategies. Oddly enough, other strategies may actually have a yield advantage. It comes down to how much yield is one willing to forgo? How much time is needed for early harvest and how one wants to spend on early desiccation?
If we look at the control in this scenario of a 3.0 and 3.5 maturity soybean, we actually saw a slight increase in yield by using an R8 desiccation. The simple yield averages and statistical analysis support this claim. Our analysis indicates any difference over 1.4 bushel was significant. This system did not, however, gain us much if any in early harvest time. So, if early harvest is the goal, perhaps we consider another cropping system.
Using an early to ultra-early soybean for the geographic area was the other treatment we evaluated. As expected, we lose a little yield by shortening our maturity. The best option here seems to be using a 2.2 maturity soybean which is about a half maturity group earlier than the recommended for the area. Results from our Mt. Hope test indicated a similar trend as well with a 1.3 maturity soybean giving us the earlier harvest window and acceptable yield. These beans (2.2 and 1.3 maturity) gained us 5 to 10 days in harvest time. There was a yield loss at about 3-5 bushels versus the fuller season check varieties and fuller season varieties desiccated early. Uniquely enough, a yield increase was realized over a traditional soybean cropping system when desiccated at the R8 reproductive stage. Another peculiarity in the data was harvest date on desiccated 3.5 maturity plots. In speaking with our research coordinator, dry conditions this summer may have had some influence on maturity in some plots.
In short, close scrutiny on what one’s end goal is needs to take place and weigh the need for early harvest against yield.
Corteva Technology Use Agreements
All growers with orders for any Corteva Agriscience brand seed product, regardless of crop or trait (including non-GM products) need to have a signed Corteva Technology Use Agreement in place by September 1. Growers should sign the Corteva Technology Use Agreement electronically at www.agcelerate.com. Signing electronically is preferable, however, paper copies are available at www.traitstewardship.com.