agriculture

We are now concluding five straight days of rain on the southern High Plains, but sugarcane aphids are still with us. I spent some time today collecting infested leaves and examining the aphids under a microscope, and I have to report that I can't find any evidence of the fungi that hammered populations on the Gulf Coast. (Although I will keep monitoring the situation.) Most of the aphid colonies I observed looked just fine, and there were some beneficial insects like syrphid fly and lady beetle larvae feeding on them. Dr. Katelyn Kesheimer, IPM Agent in Lubbock and Crosby counties, took 7 Day After Treatment data in a sugarcane aphid efficacy trial yesterday between rain events, and she reported that there was a slight decrease in aphid numbers on the untreated plots, but nothing to write home about. So the rains did not really reduce the number of aphids, but, significantly, the cooler temperatures slowed them down. Aphid development and reproduction is slower in cooler temperatu...

It Is Not Over for the High Plains Even though it is getting late in the season, sorghum is still at risk from sugarcane aphid, especially later planted sorghum. In Lubbock we are seeing leaves with thousands of aphids, and for the last two weeks many of these have been winged. These aphids have and will continue to ride the winds as they do each year. If this year is like the past three years, the aphids will spread westward and northward. Dr. Ed Bynum in Amarillo is reporting treatable populations in his area. The rains did not stop the aphids, and there is no reason to think they will stop before the first or second hard freeze. Last year we harvested sorghum at the Halfway Experiment Station after first freeze and still had plenty of aphids on the plants and in the heads. What I am trying to say is that if you have grain or forage sorghum in the field, this is no time to get complacent.   The photos below were taken at the Lubbock Research Center this morning before sunrise. Le...

After writing in this newsletter last week that fall armyworm was not a significant threat this year, Katelyn Kesheimer, Lubbock and Crosby county IPM Agent, and I visited some fields in southern Lubbock county and south to the middle of Lynn County in the last four days. I take it back; fall armyworm is very numerous in sorghum in these places south of central Lubbock County where my traps are located. We encountered fields at panicle exertion or already booted that had as many as six worms per head, with an average of 2-3 mid-sized worms being the norm. For the most part these were fall armyworms in southern Lubbock County, but corn earworms seemed to increase in frequency as we went south. In a field 6 miles west of Tahoka we were seeing something like the 70% fall armyworm and 30% corn earworm. The age structure of the populations was approximately 45% small larvae, 45% medium larvae and 10% large larvae, but of course this will change quickly. Large larvae are by far the most des...