Friday, March 20, 2015

Soybean Management Strategies to Facilitate Timely Winter Wheat Establishment

Winter wheat acres across WI have declined over the past few years due to high corn and soybean prices and late grain harvests. As farmers get ready to kick off the 2015 growing season here are a few suggestions to help get your 2016 winter wheat crop established on time. 
  • Plant early. If weather and soil conditions allow for it plant the acreage you intend to go to winter wheat first. This is regardless of which crop you plan to follow (soybean, corn silage or field corn). Remember the optimal planting date window for most of our WI winter wheat acres is the last week of September through the first week in October. In Figure 1 below you will notice a 17 day delay in planting (May 5 to May 22) led to an average 7-10 day delay in when the soybean varieties hit R7. For a majority of the varieties examined (80%) this equates to roughly 21-28 days for that soybean crop to progress to the harvest ripe growth stage so we can establish our wheat crop on time.
Table 1. Calendar date for reaching R5 (beginning seed fill) and R7 (beginning maturity) growth stage (G.S.) by planting date and maturity group (M.G.) for the 2014 growing season at Hancock WI.

Timing of G.S. Initiation
Planting Date M.G. R5 R7
5-May 1.9 29-Jul 3-Sep

2.1 3-Aug 13-Sep

2.1 29-Jul 3-Sep

2.1 29-Jul 3-Sep

2.3 29-Jul 3-Sep

2.3 1-Aug 6-Sep

2.4 3-Aug 6-Sep

2.5 29-Jul 6-Sep

2.5 30-Jul 6-Sep

2.5 31-Jul 13-Sep
22-May 1.9 12-Aug 12-Sep

2.1 9-Aug 20-Sep

2.1 12-Aug 16-Sep

2.1 12-Aug 20-Sep

2.3 12-Aug 20-Sep

2.3 9-Aug 20-Sep

2.4 12-Aug 16-Sep

2.5 12-Aug 16-Sep

2.5 12-Aug 20-Sep

2.5 12-Aug 20-Sep
11-Jun 1.9 23-Aug 27-Sep

2.1 23-Aug 2-Oct

2.1 23-Aug 30-Sep

2.1 23-Aug 2-Oct

2.3 23-Aug 2-Oct

2.3 23-Aug 30-Sep

2.4 23-Aug 1-Oct

2.5 23-Aug 2-Oct

2.5 23-Aug 2-Oct

2.5 23-Aug 2-Oct

  • Crop rotation matters. Our long-term rotation data suggests winter wheat yields are greatest following soybean, followed by corn silage and lastly corn for grain.  Therefore plan your rotation accordingly to maximize yield and system efficiency.
  • Consider an earlier maturity group soybean. Plant a high yielding, earlier maturity group soybean to help get that soybean crop harvested on time. Though later maturing varieties "on-average" produce the greatest yields, data from our 2014 WI Soybean Variety Test Results show the maturity group range that included a starred variety (starred varieties do not differ from the highest yield variety in that test) was 1.9-2.8, 1.1-2.4, and 0.9-2.0 in our southern, central and north central regions respectively. This suggests that the "relative" maturity group rating is trumped by individual cultivar genetic yield potential. Therefore growers have options to plant an early maturity group soybean that will be harvested on time and not sacrifice yield.
  • Manage for the system not necessarily the crop. If you are serious about maximizing wheat grain and straw yield on your farm one of the biggest contributing factors for both of these in WI is timely wheat planting. Make management decisions to facilitate that. *We all know what inputs can extend maturity that don't necessarily guarantee greater yields. So instead of listing them and fielding angry emails all weekend I am being strategically vague here*  As a producer is it better to sacrifice 0-2 bushels of soybean yield or 10-20 bushels of wheat grain yield and 0.5 tons of straw?  
As we all know mother nature holds the ultimate trump card on whether we will get our winter wheat crop established in that optimal window. These aforementioned strategies are relatively low risk to the farmer and regardless of what weather patterns we run into are agronomically sound.

Go Bucky!