Arkansas Rice-How Much of the Crop Is Down?09/05/2017
Rarely are Extension specialists at a loss for words – you know it’s true. After seeing the forecasts for rain and wind reduced all week long as Hurricane Harvey approached, we were all tempted to relax a little and hope for the best. And then Harvey arrived in a bad humor.
Just how much rice is down or in the process of going down remains to be seen. So many variables are in play that sometimes it is better to be lucky than good. Early indications from areas that escaped the worst weather, but still received 4 inches of rain with light to moderate winds, indicate that a significant amount of lodging is already occurring in a number of fields. Some areas received 10+” of rainfall and some received stronger winds.
In addition, those fields where only a small amount of lodging has occurred will be in a race against time. That small spot can be the first domino to fall and will push down more acres of rice. Many growers know this sick feeling all too well of watching rice melt to the ground while it’s still too wet to harvest.
What about yields now? After hearing very good yields for the past couple of weeks out of south and central areas, it’s reasonable to believe we may see some of those yields reduced due to lodging. Additionally, harvest has been minimal in the north where the majority of rice is planted. Those areas hardest hit by early spring flooded have yet to give us a yield indication and now they will have lodging to deal with as well.
The delay in harvest progress, combined with lodging and rewetting of grain may spell considerably lower grain yield and milling yields for many. After the weather events of last fall the early harvest success this year was a welcome sight. Unfortunately we have yet another, different, adverse weather event to contend with.
How Much Rice is Down?
Let’s address this specifically since this is a recurring and will be a repeated question. As of last week the state was 11% harvested for rice. With the push that occurred in advance of Hurricane Harvey let’s assume we raced to 25% completed harvest.
Since we reportedly have about 1.1 million acres in the state that means we would have about 825,000 acres left in the field. Between some fields completely flat all the way to almost untouched, let’s say we have 10% of rice currently lodged – that would be over 80,000 downed acres.
Depending on lodging severity and time spent in that condition, a conservative estimate could be 20 bu/acre lost from yield and several points of Head Rice lost from milling. Equally concerning is the potential for stain, rot, and sprouting of the grains underneath the worst lodging.
Let’s hope the forecast dry air and north wind happens this coming week as forecast so we can get this crop out.
Harvest Aids & Downed Rice
Harvest aids are tools to help us harvest rice faster and more efficiently. Any tool can be misused. My favorite example is a hammer: it’s great when it hits the nail, not so great when it hits your thumb. Same with harvest aids.
Sodium chlorate does an excellent job of desiccating rice foliage for ease of harvest and lowering grain moisture content. However, applied at the wrong time or in the wrong manner and it causes more problems than it solves.
We still have around 75-80% of rice left in the field. A number of those acres are now lodged thanks to the remnants of Hurricane Harvey. So what about applying a harvest aid to downed rice?
Sodium chlorate isn’t mobile in the plant. It’s only going to affect the parts of the plant that it touches. So in downed rice, only the plants on top are going to be affected. Bu the entire plant will receive coverage and dry down much more extremely than in standing rice. And the rice underneath? It will stay green and moist. That means you’ll be harvesting rice that is a mixture of two extremes – this always creates issues.
In this situation, the rice treated will be much drier than the untreated rice below it. The drier rice will be more prone to rewetting and drying in the field which can increase breakage and lower head rice yields. If harvested and dried with grain of mixed moisture levels, the grains that become overly dry will break up and lower milling yields. Plants that become too dry also increase the chance of shattering as the panicles dry and do not hold the grain, leading to direct yield loss.
This is not to say that sodium chlorate can’t be used if there’s any lodging in a field. The point is in fields with a high percentage of severe lodging it should be avoided.
When using sodium chlorate properly in standing rice, use a rate of 3-6 lb ai/acre. Apply it when grain moisture is below 25% (DO NOT apply below 18%). If you use the proper rate and timing, and harvest in no more than 4-7 days, research has shown no adverse effects on grain or milling yields.
Source: Jarrod Hardke, University of Arkansas Extension