July 11, 2012
The corn scouting season is on the downward slide. In fact, I will be finishing the early season corn scouting by next week. It will be interesting because I will scout young ,2 leaf corn and shoulder-height tasseling corn during the same week. The fields which are tasseling will be scouted for corn rootworm beetles to get an idea of the pressure this pest will put on the next year’s corn crop. It has been an eventful corn scouting season with plenty of weeds to identify from seedlings on up to mature plants. I only saw a few escapes, or weeds which were not completely killed by the herbicide programs. Many farmers also had armyworms moving into their corn fields (often from neighboring grass crops) and defoliating corn. Most of these fields bounced back without having to be replanted.
Recently, I’ve been in soybean fields performing weekly checks for soybean aphids. I know a little bit about these insects due to a project I did for an IPM course that I took at Alfred State, before I came to Cornell (Go Pioneers…and Big Red!!!). The WNYCMA threshold for treatment of these little green aphids is 250 insects/plant, but so far the most I’ve found is 15/plant. As usual, I’m also on the lookout for weed escapes and any other flushes of weeds which may have gotten past the residual effects of the herbicide in the bean fields. I’m responsible for scouting about 300 to 350 acres of soybeans and so far they look good and some are starting to flower.
Today, July 10, I started scouting drilled sorghum fields. Scouting the sorghum is a much like corn scouting except the populations are much higher. This farm, located in Pennsylvania, planted 103 acres of sorghum over a two day period. So far, the weed pressure looks low and the small plants appear off to a good start. I saw some bird damage, where the whole plant was plucked out, but no army worms. I understand that a second infestation of armyworms is possible, but I hope that doesn’t happen. The farmers are sick of these bugs and one made me laugh when he told me that his spray bill is ” just about as much as the national debt”. The other big project going on right now is looking for potato leaf hoppers in alfalfa. They have often been above threshold especially in the new alfalfa seedlings. I’ve become very accustomed to identifying “hopper burn”, a yellowing on the margins of the alfalfa leaves where the hoppers are feeding. The weed pressure is noted and we take crown counts of the alfalfa by counting the number of alfalfa crowns that fall within a square foot ring. Hopefully, we will get some rain soon to keep all the crops growing and to cool me off.