A June heat wave caused agricultural conditions to decline around much of the state after steady improvements over the previous month, according to Texas A&M AgriLife Extension Service experts.
May rains dramatically improved soil moisture conditions in many droughtstricken areas of Texas, but triple-digit temperatures and little to no rain in June were trending many areas back toward drought. Various crops around the state were showing stress from high temperatures and lack of soil moisture, and livestock gains likely experienced heat-related declines.
Heat wave takes toll on Texas crops The heat wave was especially harsh in the southern half of the state, where some areas experienced record temperatures.
All plants and vegetation experience heat stress during extreme daytime and nighttime temperatures like Texas experienced over recent weeks. Heat and inadequate soil moisture can stress plants, damage their cell membranes and disrupt metabolic efficiency during processes like photosynthesis and respiration, said Lee Tarpley, Ph.D., AgriLife Extension plant physiologist, Beaumont.
But the combination of high daytime and nighttime temperatures can also economically damage commodity crops, especially during sensitive growth periods like pollination and flowering.
Tarpley said the heat wave was rough on late-planted rice along the Coastal Bend. Yield potentials were high following good spring rains, but the heat arrived at a sensitive development stage for some fields – pollination. High temperatures can also negatively impact the viability of pollen, which can influence how the ultimate crop sets and fills out.
Not all the news about the arid conditions was bad. Larry Stein, Ph.D., AgriLife Extension horticulturist, Uvalde, said cantaloupe and watermelon fields in the Winter Garden and Central Texas were producing high-quality, super-sweet fruit. Irrigated vines were thriving, and brix counts were rising under the dry, hot conditions. Brix is the measurement of sugar in fruit.
But overall, Stein said conditions are declining, even for irrigated crops. Heat is not the problem though, it’s the lack of moisture.
“Vegetation is starting to burn up,” he said. “If you can maintain sufficient moisture for plants then they can cool with transpiration from the leaves, but the problem I see with the heat is stress and the other problems like spider mites and aphids, and everything takes its toll.”
Heat impacting livestock production The heat wave took a toll on more than just crops. Jason Cleere, Ph.D., AgriLife Extension beef cattle specialist, Bryan-College Station, said cattle performance in high temperatures typically declines. Higher nighttime temperatures make it a challenge to get their core body temperature down. Their grazing may also reduce as they try to avoid activity in the sun.
Cleere said Texas heat shows the importance of choosing cattle adapted to more tropical conditions like breeds with Brahman influence.
Forage production for hay, silage and grazing was very good over the last month, Cleere said. Producers were having problems with delays due to rain and excess moisture prior to the heat wave, but the arid conditions were sapping soil moisture levels quickly.
Cleere said it is critical that cattle have adequate shade and fresh water during hot conditions. A cow can drink 20-40 gallons of water per day, depending on the moisture in the grass they are consuming. Cattle should have enough shade to spread out and cool down.
“A small shade structure where they can all barely fit under might be worse than no shade if they’re piled up,” he said.
—Texas AgriLife