Jan. 21, 2010 - Conventional wisdom holds, especially during mild winters, that the lack of extended freezes leads to an abundance of insect, pests and weeds the following spring.
Despite the recent cold weather much of Texas saw, with below-freezing temperatures for several hours in a row, the vast majority of pests and weeds will do just fine.
Allen Knutson, a Texas AgriLife Extension entomologist stationed in Dallas, said Texas will have insects this spring regardless of how much cold weather is received.
"In general, there won't be much of an impact," he said. "Many of the insects, like grasshoppers, are well down in the soil. They can tolerate cold weather like we've had. The other factor is that they can multiply so quickly. Even if the weather knocked out 99 percent of them, that remaining one percent can multiply so quickly in the spring that you won't notice much of a difference."
Paul Baumann, Extension weed specialist, said weeds won't be greatly affected by a cold winter either.
"The freezes might help to a certain extent, but even most of the annuals will come back," he said. "Grass burrs will come back if it doesn't freeze out the crown, but a good freeze will help."
The deep root system of perennials, such as evening night shade, bull nettle and ragweed, protect them from freezing temperatures, unless the freeze penetrates six to eight inches deep in the soil, which rarely happens in most of Texas.
"That's why you don't have as many perennials up north," Baumann said. "The winters up there kill a lot of the perennials."
Extreme and extended freezing temperatures could put the winter wheat crop under the gun. But, Rob Duncan, an Extension small grains specialist, said the crop has withstood the colder-than-normal temperatures, so far.
"We have studies showing that most wheat varieties can withstand temperatures as low as 12 degrees for a couple of hours," he said. "You might get some slight damage, but it won't have much of an impact on yield.
"It's not like we went from the 60s down to the 20s in one day. We've had some cold temperatures for several weeks, and from the reports I've had, the wheat has done fine. Most of the varieties are pretty cold-tolerant."
In past years, hard freezes were generally good news for cotton growers, because the overwintering weevils didn't tolerate freezing temperatures for very long. That's much less a factor now that the boll weevil eradication project has reduced their numbers significantly, Knutson said.
The cold weather could be good news for peach growers, who were hit hard in 2009 by late freezes that nipped the trees in bloom. Peaches require a certain number of chilling hours -- about 720 hours -- to reach optimum quality, but those hours have to be during the trees' dormant winter stage.
Some vegetable producers have been impacted by the cold weather. Boggy Creek Farm near Austin lost about half of its winter produce when temperatures plunged into the low teens and high winds blew covering off plants that would have otherwise been protected.
"There's not much we can do about it," Boggy Creek owner Larry Butler said. "All we can do is just sit back. We'll regroup and we're going to get the greenhouses fired up, and start getting more transplants ready."
As for the pests and weeds, there may be a few nuggets of good news to come from the cold weather.
"There are a few insects that are limited by the cold," Knutson said. "Fire ants have a hard time getting established much farther north. Most of Texas is right on the edge of their distribution. It really depends on what kind of insect it is. Most people will have to deal with grasshoppers year in and year out.
"The Africanized honeybee might get knocked back a little bit. They don't survive the cold as well as the European honeybee, so we might have fewer of them than usual.
"Other than a few things like that, you can be pretty sure you're going to have insects in your pasture this spring."
