Integrated Pest Management for August 13, 2012

Cotton

Cotton is maturing rapidly with nodes  above white flower ranging from 0 to  7, with many fields now at 5 nodes or less. This means that most fields are  now in “cut out’. Dryland, limited irrigation

and early planted cotton now range from 0 to 3 nodes above white flower. Many fields have adjusted

fruit loads due to heat and are shedding many squares and small bolls.  Dryland has been hit hard by  recent heat wave and no rain. These fields  are completely wilted in the heat of the day and have only retained a few bolls per plant. Well irrigated cotton has bolls set from top to bottom and most first positions have been retained to form a boll.  Insect pressure remains light. Lygus have been reported at 5 per 100 plants and boll damage has been light. Cotton bollworm, beet armyworm and loopers remain light.  Beneficials are excellent with spiders  being the most common. Lacewing larvae and big eyed bugs have been on the increase.

Sorghum
Corn earworm infestations have ranged from very light to very heavy in headed sorghum. Overall infestations have been much lighter than anticipated. Fall armyworms have been found in heads sampled, but have only constituted a small portion of the head worm complex.  Greenbugs have been on the increase in several fields and not found in others.  Where populations are on the increase

parasite activity has been found. The most common parasite has been Lysiphlebus testaceipes which produces the tan or golden brown mummy. Aphelinus parasites have also been observed attacking greenbug colonies, which produce a smaller black mummy. Once parasitized greenbugs reaches 20% of the population an insecticide treatment is usually necessary.  Stinkbugs and Lygus bugs have also been found in head samples, but would generally be classified as light at this time.

Banks grass mites generally remain light, but some have reported cases of treatment needed.  Beneficials have been excellent in head samples with pirate bug adults, crab spiders, assassin bugs and big eyed bugs commonly found.

Corn

Banks grass mites are still active in area corn. The heaviest populations have been found in corn at the dent stage.  Continue to scout corn for this pest until  corn reaches full dent with the moisture

line 50% down.  Fall armyworm remain light with an occasional  larvae found feeding on ears.