Measurable rainfall again crisscrossed the region late last week and last weekend dropping moisture for most of us. The latest rounds did not have any damaging weather with them that I am aware of like some swaths of previous rounds did.
With extended cool periods of last season and the resulting quality cotton fiber problems (aided by a late and rough start) fresh in our minds, a few days brought on concerns for our cotton quality to the surface. With a relatively better start to this season, the vast bulk of this season being hot and dry, and the general earliness of the cotton, I do not expect to have many lint quality concerns this year. At least very many issues arising from any similar causes as last season.
There are and always can be a few exceptions that should be managed appropriately but we have started spotting several fields with their first open bolls already. With temperatures returning to the upper 90’s with sunshine, this crop has the potential to keep rocking into harvest on the early side.
On the pest front, few things have changed from last week. Weed pressure is ever-present while bollworms and sugarcane aphid potential problems are high. For bollworms/headworms in all major crops, and to a lesser extent the sugarcane aphid in sorghum, are nearing chronic potential problem levels week in and week out but the number of fields where they are actually economic is quite low.
In fact, most fields are dropping in insect activity quite rapidly despite the majority still having some level of pest susceptibility. Both pest and beneficial are crowding ever heavier into a select few lush and or late fields sending their insect activity ever higher off the charts.
Finding those fields, evaluating their economic situation while making sure the balance of the susceptible fields do not have any pest ‘settling’ or ‘overspill’ becomes a priority for us as we ride the remainder of the growing season out.
Our program cotton ranged in stage from a late 4.5 NAWF (nodes above white flower) to 1st open boll with just 4.4% of fields not in absolute cut-out but 16.2% showing their first open bolls. With today, August 24th, being the last aver-age effective bloom date, we are pleased to see only a few fields still blooming squares into bolls.
Those later fields do have a chance of setting harvestable bolls, especially with a good fall, but the odds get longer with each passing day from this point on. It still looks like we will be ahead of a ‘normal’ harvest ‘schedule’ this year.
Bollworms remained our prime pest of concern this week, but had no fields reach ET this week. In fact, we had drastically fewer fields getting much insect attention at all. We only found 26.5% of our fields found with bollworm eggs and only 2.9% with more than 5,000 eggs found per acre.
AgFax Weed Solutions
Our few already treated fields are still attractive to the moths for egg lay but residual and predation are still holding worms from reestablishing into a problem. I estimate about 85% of our fields are still at risk for worms, very few seem attracted so far.
We are getting reports of selected fields from across our three counties of cotton fields that are reaching ET still. From these reports, they too are the lusher and later fields too. Our thresholds remain at 8,000 to 10,000 worms per acre or 6% harvestable fruit damage for all non-Bt and Bt types alike.
We are finding most cotton fields with a scattering of Lygus and a somewhat persistent stink bug population this week. Both of these plant bugs remain sub-ET at, about 1 pest / 18 row feet or lower if present. We found no aphids in our program fields and spider mites had trouble continuing in a cooler and wetter week with beneficials adding to our benefit too.
Beet armyworms, true armyworms, and cabbage loopers can be found in most non-Bt fields this week but at such a light rate consistent detection was difficult from data set to data set. Our highest population for BAW toped at 5,945 / acre.
For the beet armyworm, we have a report of a field in northwestern Hale that neared the ET for of 50,000 BAW per acre (or >10% infested plants and noted fruit damage) that were alongside economic bollworms. With the exclusion of pyrethroids, most newer products labeled for bollworms have great activity on BAW also.
Our program sorghum this week ranged in stage from boot to dough. Our untreated sorghum fields were what primarily counted as ‘attractive’ to the headworms, almost exclusively made up of bollworms this week.
Much like our treated for bollworm cotton fields, our treated for headworm sorghum fields are holding up well with residual and predation holding the headworms from reestablishing. Our highest population among our treated fields were 0.02 small headworms per head.
Conversely, our yet untreated sorghum experienced a huge headworm population jump averaging 3.6 headworms per head with small worms accounting for 2.2 of these worms per head. This week, bollworms made up 98.2% of this headworm population and fall armyworms made up the few remaining.
Even with this high and increasing population the economics of the price of grain and yield potential versus the cost of application (SCA population and beneficial defending product selection needed here) indicate that even this population is borderline ET. All indications are that this population will continue to grow with additional eggs and moth activity noted in field. We recommended treatment in this situation.
Our sugarcane aphid populations continue to be of interest. Our research plots are experiencing extended heavy pressure while the aphid is slow but steady to increase in other fields and remains hard to find in treated fields and areas if the treatment was a ‘good’ one.
In our seed milo fields, the treatments almost completely cleaned the aphid out and they remain hard to find. In our research plots, we will be able to share interesting data again this winter that show differences in coverage resulting from application type and GPA rate resulting in variable control. We are also noting several other differing results of interest we hope to share soon.
All other pests were very light. Spider mites and green bugs are among the other pests noted in our program fields, but they were well below ET with very high numbers of predators in-field.
Our two program corn fields are past economic pest damage but I have made a few spot checks for fungal development in the ears. So far, I am finding none that cannot be explained by extreme tip feeding or side ear pest feeding. This does not seem apart from ‘average’ damage and fungal occurrence for now and I do not have any information from the early harvested fields yet.
Fields still not at 15% starch line should be VERY attractive to ear pests, but the cooler weather should be limiting mites.