A welcome soaking rain this week brought much needed relief to many rice and soybean acres. Those just trying to get started with harvest had to pause, but only for a day. Overall, the rain was of large value on saving some pumping costs across a lot of acres on an already expensive year.
Precipitation expectations for this weekend beginning Sunday were pretty high when this week began but are now fading somewhat. Southeast AR still has the greatest chance of large rainfall amounts, with central and northeast areas potentially only receiving small amounts. Only time will tell where the bulk of the rain sets up, but it looks like our friends on the Gulf still in the middle of harvest may get problematic rain totals.
Disease pressure has remained low, but the lower temperatures combined with some rain and heavier dews have increased some activity. In particular, sheath blight activity has increased. In many situations it’s reaching the upper canopy very late in heading rice nearing maturity – well beyond the point at which it can hurt yield. However, if we get into harvest delays it could lead to some increased lodging.
Harvest progress is extremely preliminary at this stage. But it’s nice to be able to say that yield and milling reports are good on the limited number of fields cut to this point. The exact temperature conditions rice went through at various stages are extremely variable so there are a lot of unknowns about how yield and milling will play out, but right now the crop looks strong. The combine will tell.
Let us know if we can help.
Fig. 1. NOAA 7-day precipitation forecast. Click Image to Enlarge
Late Season Rice Stink Bug Management
Rice stink bug (RSB) numbers have increased quite a bit over the past few weeks. The calls we are receiving mainly revolve around the youngest rice just beginning to head. In the trials we sprayed and sampled this week, we were averaging around 25 RSB per 10 sweeps. This is double of what we were catching a month ago.
On a positive note, Endigo ZC and Tenchu both are providing excellent control of these populations. Lambda and Mustang Maxx are both pretty poor, at only about 45-50% control. At this point in the season, I would only use a pyrethroid if 50% control and essentially no residual is good enough.
As we keep draining and harvesting rice, the latest or greenest rice is going to become even more attractive to RSB. Using a product like Endigo or Tenchu will provide upwards of 10 days of control of rice stink bugs, and in many cases, we have seen longer residual than that.
The last thing we want to mention is when can termination of RSB applications begin. We have done quite a bit of work on this and have determined that when we hit 60% straw-colored kernels on a panicle, we can terminate RSB applications (Fig. 2).
We do want to be pretty clean going into 60% straw coloration, because at high populations of RSB, some damage can occur after 60% straw-colored kernels. The only time we will not recommend terminating at 60% is if we have several days of rain in the forecast.
This can soften kernels and make it easier for RSB to damage kernels that would otherwise be past the point of receiving damage from rice stink bugs. Good luck finishing out this crop, and feel free to call us with any questions.
Fig. 2. Panicles in the center picture are 60% hard dough or beyond.
