MISSISSIPPI STATE -- Unseasonably cold weather in May hurt cotton and led to increased numbers of thrips in many crops, but a bigger problem has been too much or too little rain.

Charlie Wax, state meteorologist at Mississippi State University, said May temperatures ranged from 5 to 9 degrees below normal. The Coast was comparably colder and drier than the rest of the state. Many areas received rain the last few days of May.

Charles Snipes, northwest district cotton specialist with MSU's Extension Service in Stoneville, said Delta temperatures in the upper 40s at night and a north wind for three days took a great toll, especially on cotton fields.

"Cotton has to accumulate a certain number of heat units to grow," Snipes said. "It needs hot days and warm nights, and when it's cold and cotton can't grow actively, low thresholds of thrips create more injury than they do under normal conditions."

Snipes said in addition to the cold making the plants more susceptible to damage from these insects, farmers in the North Delta have been unable to plant all their cotton because of wet weather.

Alan Blaine, Extension soybean specialist, said weather has hampered soybean growth.

"Soybeans stopped growing for a little while, either from dry weather or cool temperatures, and growers were concerned about thrips damage," Blaine said. "It takes tremendous thrips pressure to justify treatment on soybeans, and we haven't run into any fields yet that needed treatment."

To soybean farmers, dry weather was a bigger concern through May than was cold weather. Blaine said fields south of Highway 82 really needed moisture at the end of the month.

Erick Larson, Extension grain crop specialist, said the cool weather didn't hurt the corn crop, but caused a condition on the leaves known as sunscald that shouldn't affect yield.

"It's a silvering of the leaves that occurs in irregular blotches on young leaf tissue on the side exposed to the sun," Larson said. "It's purely cosmetic and caused by cool, clear night conditions and bright, sunny mornings."

Larson said what has hurt the corn has been dry weather, especially in the southern part of the state. Cool weather has helped the plants tolerate the drought better, but north of Highway 8, saturated conditions in low-lying fields have stunted corn and kept farmers from applying needed nitrogen fertilizer.

The dairy industry in Mississippi also has been affected by dry conditions. Wesley Farmer, Extension dairy specialist, said most dairies in South Mississippi, where the majority of the state's dairy industry is located, have not had any significant rain since April 6.

"That's about the time a lot of our producers plant corn for silage. Our crops are suffering just like the row crops in the Delta without irrigation," Farmer said. "We've lost the early production of summer perennial grass. It's going to cut into our hay production and grazing."

The cool weather was good for the dairy cows, however.

"That little cool snap was wonderful, but without the rain to grow crops, it was a short benefit," Farmer said.