Sunday, January 5, 2003
By Nathan Riggs, IPM Extension Agent (Fire Ant Program)
Texas Cooperative Extension-Bexar County
In my five years at the Bexar County Extension office, I have come to recognize patterns throughout the years as to when certain insects would be active. For example, scorpions tend to be most active in May and June, and chinch bugs do their damage in July and August. These are just average trends observed over the past five years. Having said this, 2002 should have an asterisk as being a mostly unusual year for bugs and such! How many times in 2002 did you utter the words, “I’ve lived in San Antonio (fill in the blank) years and I’ve never seen this (fill in insect or phenomenon) before.” Maybe you heard someone else utter them. Either way, 2002 was truly full of surprises around each corner.
The cause of all this variability: rain, rain, rain and mild temperatures. All of these conditions were perfect for lush vegetative growth on all trees and plants. This lush growth provided an abundant food for the plant-feeding insects such as aphids, scales, grasshoppers and various caterpillars. At last check, the San Antonio rainfall for 2002 was somewhere between 12 and 14 inches AHEAD of normal! Our rainfall this year is typical of what Houston receives on the average. WOW!
With rainfall comes mosquitoes, and hoards of mosquitoes at that! The fact that West Nile Virus reared its devious head in 2002 just made the mosquito issue even larger. Expect a hangover of high mosquito populations to continue for 2003 as well. Buy plenty of repellant and be ready!
All of the lush vegetation produced an explosion of grasshoppers as well. Normally, grasshoppers attack garden and ornamental plants after they exhaust their normal resources of weeds and grasses. This year there were so many grasshoppers that they just spilled over into our landscapes and gardens. Expect a carry over into 2003 for these critters as well. Consider broadcasting some Nolo Bait next spring as the baby grasshoppers appear. It contains a protozoan organism that kills very young grasshoppers, but not older or adult grasshoppers.
Not only did we see hoards of grasshoppers, but many folks’ homes were invaded by inch-long stone centipedes and millipedes. These arthropods responded in force to the vast amount of rotting vegetation produced by the bountiful rains. Both of these organisms feed on decaying vegetation and are considered to be somewhat beneficial. They invaded homes to escape from excessive moisture and subsequently died because indoor humidity is too low for their survival.
Webworms in 2002 were much less of a factor than normal. This is directly linked to predation by very high populations of paper wasps and yellowjackets that have been building up over the past two or three years.
Finally, there are fire ants. For fire ants, 2002 was a “Dr. Jekyll/Mr. Hyde” type of year. Until the deluge that occurred in July, fire ants had been relatively few and far between for two years. Once the rains stopped, there were fire ant mounds everywhere! The super-saturated ground really brought them to the surface-for all to see. As 2002 drew to a close, the fire ant population was not as apparent due to dry conditions, but these stinging menaces should be ready to go when spring rolls around. Consider broadcasting a bait such as Amdro®, Logic®, or Extinguish™ in your lawn when the weather warms in April. Remember to use a hand-held seeder and spread one pound of bait per acre.
This article can’t begin to touch all of the weird and wacky biological events that marked 2002. However, it does prove that trends can change with the drop of a hat-or perhaps a drop of rain. Happy 2003!