Rice Underwater – Will It Last?

DR. JARROD HARDKE

FAYETTEVILLE, ARK.
   The heavy rainfall has led to fields holding deep water at the bottom and rivers backing out to meet it. For the second time this season the questions have started rolling in – how long will this rice survive?
   If rice was newly planted and did not have a chance to germinate there’s a chance it will sit there for a prolonged period. But that’s probably not what happened. If it’s trapped under the soil surface, it won’t emerge through both the soil and water, rice will just sit there until it dies or the water leaves. Usually you have somewhere in the range of 6-14 days to get the water off before all bets are off. Results in this window can still be extremely variable depending on environmental conditions and the water conditions.
   Emerged, seedling rice that is somewhat established can surprise you. If water conditions are muddy and stagnant the rice may not last long at all, but if the water is moving and let’s some light through rice will last a while. Rice has come out of floodwaters after more than 21 days and looked a little small and stretched, but alive.
   The bigger rice gets beyond seedling stage, the faster it’s going to die if under deep water. Late tillering rice and beyond I’ll say that 7 days or less underwater and it will be fine; between 7-10 days and it’s a toss-up; over 10 days and it’s gone. That metric seems to be almost concrete for reproductive stage rice.
   Sometimes it’s better to be lucky than good in these situations. But if you’re approaching a week underwater and you have taken drastic measures to get the water off, now would be the time or that may be a replant. ∆
   DR. JARROD HARDKE: Rice Extension Agronomist, University of Arkansas