Initial yield reports have been mixed. The general idea is that yields are down some from last year, which was expected considering that exceptional crop.
Some lower yields have been encountered already, but those appear to be mostly due to difficulty managing some of this earliest rice. The cool, continued wet conditions early made it very difficult for rice growth and subsequent fertilization timing for rice planted really early.
By this time last year we had harvested our first two planting date studies. This year, they won’t be mature enough until next week. We’ll provide an update on those results as soon as we have it and maybe they can provide some additional insight into the year and our expectations.
The upcoming forecast also leaves something to be desired for harvest. Rain yesterday and now through the weekend will put a stop to things. That will be followed by what look like good harvest conditions, but not good finishing conditions for the rest of the crop trying to finish up as we move into the mid 80s for highs and 60s for lows. This could start to drag out.
Don’t Drain Too Early
Given the lateness of this crop and the current weather pattern, many are considering trying to get fields drained soon. While we want to get the ground dried out and move toward harvest, draining too early can have negative consequences.
We can agree that when temperatures are mild and additional rainfall is expected, we can stop pumping early (~14 days after 50% heading). However, actually pulling the water off the field early is not our goal at that timing. At this stage we want to make sure we do not stress the plants as we complete grain fill.
It’s been a little while since we’ve revisited drain timing in research, but the general take home message remains the same. As we’ve moved to higher yielding cultivars with longer panicles that take longer to complete grain maturation, the negative impact of draining too early could be even further exaggerated. Table 1 illustrates the optimum drain timing to be approximately 25 days after 50% heading (our current recommendation for long grains).
This research is based on silt loam sites, so clay soils could be drained a little earlier as they retain moisture better. But limited data from 2006-2007 indicates that the optimum drain timing for clay soils is in line with the data presented below for loamy soils.
Remember that we want to target approximately 25 days after 50% heading and have about 2/3 straw colored kernels on loamy soils, or 1/3 straw colored kernels on clayey soils. Remain conservative in your decision to drain as we can lose yield by going too early – and this is not a year to leave yield in the field.