I was hoping that after the last rain that we might see some improving conditions. With our high temperatures and lack of rainfall, I was not surprised that the Drought Monitor has upgraded Southeast Missouri to reflect the dryer conditions.
This week our cotton growing area is either in the extreme or severe drought categories. Last week we had over 8 percent of Missouri in the Bootheel area in the severe drought category. This week, the extreme drought covers 8.06 percent.
Looking at the Missouri Crop Progress and Condition Report for the week ending June 17, shows that in the Southeast region, 45 percent of the topsoil moisture supply was in the very poor category with 44 percent listed as poor. This leaves only 11 percent considered adequate.
Cotton squaring and beyond was 36 percent, 10 days ahead of 2011 and 8 days ahead of normal. Cotton condition was 6 percent very poor, 25 percent poor, 46 percent fair, 21 percent good, and 2 percent excellent. The cotton that is thriving is irrigated and in most cases was the earliest planted.
The University of Missouri Cooperative Media Group issued a news release on June 11, entitled, ?Flash drought still an issue despite recent rain relief.? Dr. Pat Guinan, state climatology with Extension?s Commercial Agriculture Program that when the climatologists look at spring ? from March to May ? it?s just one record-breaking event after another. ?It was our warmest spring on record, which blew the previous record set in 1977 out of the water by 3 degrees,? Guinan said. ?That?s significant because typically you break a monthly or seasonal record by a smaller margin.?
You can see this impact in the field. MU Extension specialists across Missouri observed uneven soybean stands and corn fields where leaves roll from lack of moisture and heat, both signs of drought stress. Pastures and lawns also have that characteristic ?crunch? when walked upon due to the browned, dead or dormant grass needing a drink.
Southeast Missouri began experiencing the dryness in April, but it has since spread across the rest of the state especially after the first week of May.
The reason that we are having this drought according to Dr. Guinan is because of an Omega blocking effect. This is the result of low pressure troughs on the east and west coasts and a high pressure ridge in the center of the country. When this occurs, this keeps the clear skies over our region with little clouding and rain. In talking with other climatologists, once the patterns develop, it takes a major weather event to reverse the conditions.
While driving in the Clarkton area earlier this week, it could not have been clearer as to the impact of the drought. I saw corn outside of the center pivot that had severe drought symptoms. It was about two feet tall and was very brown and was dry looking. The stunted plants had symptoms of nutrient deficiency because the roots were not able to take up the nutrients. This corn was contrast with corn that was irrigated and was over head high. The corn that was irrigated was filling out nicely. The dry land corn was not pollinated very well and the ears not developed. The situation was similar with soybeans.
I have seen cotton fields that had very poor stands caused by the drought conditions. Dry land cotton is also showing drought stress with both nitrogen and sulphur nutrient deficiencies. Most likely the nutrients are in the soil.
I have spent a great deal of time in watermelon fields and have also seen the impact of the drought. Although the crops are irrigated, the plants have been hit very hard by the two-spotted spider mites. Two-spotted spider mites, Tetranychus urticae, are tiny eight-legged arthropods with two large spots on both sides of the body. Mites are typically found on the undersides of leaves, but may colonize entire plants during outbreaks. Silk webbing on the undersides of leaves, and bronzing, stippling and burning of leaves are characteristic signs of spider mites. Damaged leaves drop from the plant. This pest seems to explode during hot, dry weather.
I saw a field last week that had severe spider mites. There were a few minor disease problems. As soon as I drove to the field?s edge, I knew immediately that spider mites had been a problem. This was the morning after the rain and I could find very few mites because they are hard to find after a rain. After treating for spider mites, the field has shown a remarkable recovery. The plants are now setting fruit but the damage has been done and there will be a delay in harvest.
According to the weather forecasts, we are expected to be dryer than normal during June, July, and August with equal, normal, and below normal rainfall.
The heat units or degree day-60 units for May 1 planted cotton through June 14 were 688 compared with 533 for the same period last year. Last year, much of our cotton was planted well after the recommended planting date.
We will need to monitor our crops for insects and disease. Although we are earlier this year, we can?t allow anything to set the crops back.
As I have mentioned, irrigation really pays off. This season, producers are spending a lot of money for diesel, gas, or electricity to water their crops. This is likely to continue for most of the season. While irrigation is expensive, growers don?t have much of a chance without it.
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