{"id":238,"date":"2015-07-09T15:00:15","date_gmt":"2015-07-09T15:00:15","guid":{"rendered":"http:\/\/agrilife.org\/mid-coast-ipm\/?p=238"},"modified":"2015-09-24T16:49:35","modified_gmt":"2015-09-24T16:49:35","slug":"economic-thresholds-of-pests-in-sorghum-heads","status":"publish","type":"post","link":"https:\/\/agrilife.org\/mid-coast-ipm\/economic-thresholds-of-pests-in-sorghum-heads\/","title":{"rendered":"Economic Thresholds of Pests in Sorghum Heads"},"content":{"rendered":"

\"Sorghum<\/a>Maturity of sorghum fields varies widely across the Texas Coast.\u00a0 While some fields have had harvest aids applied and are being harvested this week, other fields are just beginning to head.\u00a0 Sorghum maturity is complicated even more in some fields which have parts of the field blooming while other areas of the field are at hard dough.<\/p>\n

Varying maturity within a field makes for tough decisions on what to protect from insect pests.\u00a0 Will the young heads be mature when the more mature heads are ready for harvest?\u00a0 Can the areas of the field with different maturity be harvested separately?<\/p>\n

We are finding midge<\/strong> in blooming heads of some fields and stink bugs<\/strong> and headworms<\/strong> can be found in many fields.\u00a0 Once the field has reached hard dough, it is no longer susceptible to economic damage from these insects.<\/p>\n

When finding headworms smaller than 1\/2 inch, remember these worms usually have low survival rates and they don’t feed much until they are larger.\u00a0 This is why the threshold for medium sized worms (<1\/2 inch) is so much different than that of large worms (>1\/2 inch).<\/p>\n

Most fields still have sugarcane aphids<\/strong> at low levels.\u00a0 I have found fields nearing treatable levels of sugarcane aphids only to have the beneficial insects (lady beetles, syrphid flies, green lacewing larvae and parasitic wasps) reduce the populations to near zero within a few days.<\/p>\n

As harvest nears, keep an eye out for increasing aphid numbers; especially on the flag leaf.\u00a0 Last year we saw aphids move from the leaves to the head following a harvest aid application.\u00a0 Aphid populations have began to increase in the Rio Grande Valley as they begin harvest.\u00a0 We may see a similar trend in our sorghum fields.<\/p>\n

We have good economic thresholds for sorghum midge, rice stink bugs and headworms.\u00a0 These economic thresholds are available in two methods.\u00a0 One is on the internet at the links below and will give you an ET in insects per head.<\/p>\n