Cotton:  Only 10-20% of the acres are at legitimate risk to insect pests at this time.  These are the later maturing fields, mostly those planted in the river bottoms after flood waters receded.  These same areas are in the midst of a large bollworm flight, and plant bugs are also present.  Thus, some fields need treatment.  We are mostly talking about PHY375 WRF.  The WideStrike technology is providing good protection but being overwhelmed in some circumstances.  Consider adding 0.5 lb Acephate/Orthene to any pyrethroid applications.  The Acephate will enhance control of bollworms and also help control late plant bug infestations.   Unfortunately, the performance of pyrethroid insecticides against bollworms has slipped to a level that they require a tank-mix partner in high pressure scenarios.

Remember, you are rolling the dice if spraying insecticides on fields much after September 1st.  At this time, at least during an average year, bolls less than 15 days old will have less than a 50% chance of maturing before a killing frost.  If you elect to spray after this date, you should consider doubling the suggested treatment threshold for bollworms (and not spraying for plant bugs at all).

Soybean:  A horse of a different color.  Soybean fields need to be protected from insect pests through R6 (full seed).  As we get busy harvesting corn and defoliating cotton, don’t forget to check your later maturing bean fields for stink bugs, loopers and other pests.  There have been reports of loopers, but none of populations at treatment level (average of 19 larvae per 25 sweeps).  Remember – do not expect synthetic pyrethroids to provide acceptable control of soybean loopers.  We’ve been fortunate that stink bug infestations have been relatively mild, but this can change quickly during September as bugs concentrate is later maturing fields.  Continue to use a threshold of 9 stink bugs per 25 sweeps (36/100) through R6.

The bad news … bollworms continue to require treatment in some fields in the Mississippi River bottoms.  Pay special attention to any fields that are still blooming, especially fields with a relatively open canopy.  I’m hearing that Belt is running in short supply, leaving Steward or a tank mix of a pyrethroid and acephate the remaining alternatives.  Of course, the really bad news is that dry weather is rapidly reducing yield potential of late planted fields in many areas.  Hopefully some late rains will justify the added expense.