Arkansas IPM Report – June 24, 2022

by Glenn Studebaker, Extension Entomologist/IPM Coordinator, and Courtney Spinks, Program Associate Row Crop Entomology - June 24, 2022

This report contains information on Arkansas moth trap catches for Southwestern Corn Borer and Bollworm, along with a Blister beetle update.

Southwestern Corn Borer

Pheromone trap catches for southwestern corn borer are beginning to pick up in Woodruff County in the Cotton Plant area. Trap catches in other areas of the state remain fairly low. Growers with non-Bt hybrids in the area of south Woodruff County should consider applying an insecticide with a long residual for southwestern corn borers. Residual insecticides are listed in the table below. The rate indicates the amount of product that is applied per acre of crop. The restricted entry interval (REI) indicates the amount of time that entry into an area sprayed with the corresponding product is required. The pre-harvest interval (PHI) is the amount of time required between the corresponding insecticide application and harvest of the crop.

Table 1. Residual insecticide recommendations for growers with non-Bt hybrid corn.

Woodruff County

Figure 1 indicates the Southwestern Corn Borer moth trap catches reported for the data period of June 9 – 23, 2022 in Woodruff County. Locations CP3 – CP11 all reported trap catches on June 23, 2022. Locations CP8 – CP11 have all seen an uptake in the number of moths captured per trap.

• Locations CP3 – CP7: under 20 trap catches
• Location CP8 and CP11: between 40 to 60 trap catches
• Location C9: between 100 to 120 catches
• Location C10: between 140 to 160 catches

Figure 1. Southwestern Corn Borer Moth trap catches for Woodruff County (June 9 – 23, 2022)

The x-axis of the graph indicates the 11 different locations moths were monitored. These locations, from left to right on the axis, are F1, F2, CP3, CP4, CP5, CP6, CP7, CP8, CP9, CP10, and CP11. Each location has 3 corresponding monitoring dates that indicate the number of moths found per trap each week. These numbers are located on the y-axis and range from 0-160 moths per week. Blue bars indicate moth trap catches on June 9, 2022, orange bars indicate trap catches on June 16, 2022, and gray bars indicate trap catches on June 23, 2022.  

Blister Beetles

Striped blister beetles have been showing up in several areas. Blister beetle adults are defoliators and prefer to feed on broadleaf plants. This species of blister beetle moves in “swarms” with large numbers congregated in an area and can often be found feeding on pigweed. There have been several reports of small areas of soybean fields being defoliated by these pests. Generally, infestations will be concentrated near field edges or in areas of the field with pigweed or other broadleaf weeds. In these areas, soybeans may be completely defoliated. However, because they rarely occur across an entire field, control can be achieved by treating only the infested areas.

Bollworm

We are experiencing a pretty significant bollworm moth flight. Some areas are catching over 2,000 moths in a 7-day catch. Reports are coming in of bollworm being found in flowering soybeans. Some are picking up 6 to 8 worms per 25 sweep sample in R-2 soybeans. Growers are encouraged to keep watch for bollworm larvae in susceptible crops such as soybean, grain sorghum or cotton. It is likely with such high moth catches that we will see increased numbers in these crops. Consult publication MP 144 Insecticide Recommendations for Arkansas for a list of recommended insecticides and treatment thresholds. Graphs of trap catches by county are shown below.

This work is supported by the Crop Protection and Pest Management Program [grant no. 2021-70006-35512/project accession no. 1027188] from the USDA National Institute of Food and Agriculture.

Arkansas County

Arkansas County is experiencing an increased occurrence of bollworm moths at all locations monitored for the data period of June 2 – 20, 2022 (Figure 2). The Bayou Meto and Wesley locations reported trap catches just under 20 and 40, respectively, on June 20. The Doughboy and Gillett locations reported higher moth activity on the same day, at approximately 100 and 120, respectively.

Figure 2. Bollworm Moth Trap Catches for Arkansas County (June 2 – 20, 2022)

The x-axis of the bar graph indicates four locations monitored for bollworm moths weekly: Wesley, Bayou Meto, Doughboy, and Gillett. The y-axis scales from 0 to 140, indicating the number of moths per trap captured each week. Colored bars indicate moth captures on June 2, 2022 (blue bars), June 13, 2022 (orange bars), and June 20, 2022 (gray bars) at each location.

Clay County

Bollworm numbers have increased dramatically throughout Clay County for the data period of June 8 – 22, 2022, and should be closely monitored and managed. Four of the six locations reported trap catches exceeding 2,000 moths per trap on June 22, 2022 (Figure 3). Of these, the Bowers location reported the highest trap catches at just over 3,500.

Figure 3. Bollworm Moth Trap Catches for Clay County (June 8 – 22, 2022)

The x-axis of the bar graph indicates six locations monitored for bollworm moths weekly: Brock P, Brock H, Bowers, Scott, Pollard, and Brown. The y-axis scales from 0 to 4,000, indicating the number of moths per trap captured each week. Colored bars indicate moth captures on June 8, 2022 (blue bars), June 13, 2022 (orange bars), and June 22, 2022 (gray bars) at each location.

Craighead County

Bollworm moth trap catches were reported at eight locations in Craighead County on June 10 and 17, 2022 (Figure 4). A spike in bollworm numbers occurred on June 17, at the Caraway and Christian locations nearing 250 and 450, respectively. Others reported above the treatment threshold on the same day. Continue to monitor and manage the pest closely.

Figure 4. Bollworm Moth Trap Catches for Craighead County (June 10 and June 17, 2022)

The x-axis of the double-line graph indicates the eight locations monitored for bollworm moths weekly: Bay, Caraway, Christian, Clark, HWY158, Lake City, Monette, and Parish. The y-axis of the graph scales from 0 to 500, indicating the number of moths captured per trap. A blue line represents moths captured on June 10, 2022, and an orange line represents moths captured on June 17, 2022.

Desha County

All four locations monitored in Desha County reported high bollworm moth activity for the single reporting day of June 24, 2022 (Figure 5). Moths captured per trap ranged from slightly under 100 at the McAuther location to over 850 at Tillar.

Figure 5. Bollworm Moth Trap Catches for Desha County (June 24, 2022)

The x-axis of the bar graph represents June 24, 2022, the monitored date of bollworm traps. The y-axis scales from 0 to 1,000 and indicates the number of moths captured per trap. Colored bars of blue, orange, gray, and yellow represent the number of moths captured at each location, respectively: Dumas, Backgate, Tillar, and McAuther.

Drew County

High counts of bollworm trap catches were recorded at the two locations in Drew County for the reporting date of June 24, 2022 (Figure 6). Moths captured at the Tillar location exceeded 450, and Monticello reported just under 300 trap catches.

Figure 6. Bollworm Moth Trap Catches for Drew County (June 24, 2022)

The x-axis of the bar graph indicates the date bollworm traps were monitored, June 24, 2022. The y-axis scales from 0 to 500 and indicates the number of moths captured per trap. Moths captured are represented by blue and orange bars for the Tillar and Monticello locations, respectively.  

Greene County

Bollworm moth trap catches at Greene County collected data at six locations from June 6 – 27, 2022. All locations reported high bollworm moth activity (Figure 7). Schugtown was the only location with trap catches reported on June 6 and 13. On June 20, moth trap catches were reported at all monitored locations. Lorado and Stanford trap catches were the highest on June 27, nearing 1,400 and 1,800, respectively. On the same date, Marmaduke and Stonewall each reported approximately 400 catches, and Bard reported 600.

Figure 7. Bollworm Moth Trap Catches for Greene County (June 6 – 27, 2022)

The x-axis of the bar graph indicates the location of bollworm traps monitored: Bard, Marmaduke, Shugtown, Lorado, Stanford, and Stonewall. The y-axis scales from 0 to 2,000 and indicates the number of moths captured per trap. Colored bars of blue, orange, gray, and yellow represent the number of moths captured on June 6, June 13, June 20, and June 27, 2022, respectively.

Lawrence County

Lawrence County reported bollworm moth trap catches at five locations on June 21, 2022 (Figure 8). The Wall and Beary locations each exceeded 1,200 trap catches, with Jones and Binkley slightly over 200 and 100, respectively. 

Figure 8. Bollworm Moth Trap Catches for Lawrence County (June 21, 2022)

The x-axis of the bar graph indicates the monitored date of bollworm traps, June 21, 2022. The y-axis scales from 0 to 1,400 and indicates the number of moths captured per trap. Colored bars of blue, orange, gray, yellow, and light blue represent moths captured per location at Wall, Jones, Beary, Stone, and Binkley, respectively.

Lonoke County

Lonoke County reported average bollworm moth trap catches across locations for May 26 – June 23, 2022 data period (Figure 9). The lowest of the average trap catches was approximately 50 on June 9. The highest reported average was slightly under 450 trap catches on June 16. The data reporting period closed out on June 23, nearing an average of 250 bollworm moth trap catches.

Figure 9. Bollworm Moth Trap Catches for Lonoke County (May 26 – June 23, 2022)

The x-axis of the bar graph indicates the dates bollworm traps were monitored: May 26, June 2, 2022, June 9, June 16, and June 23, 2022. The y-axis of the graph scales from 0 to 500 and indicates the average number of moths captured per trap. Blue bars represent the number of moths captured for each data reporting day across locations in the county. 

Mississippi County

Mississippi County reported bollworm moth trap catches for the May 31 – June 21, 2022 data period. Locations include Bassett, Osceola, Blytheville, Manila, and NEREC (Figure 10). NEREC reported a significant increase in the number of moths per trap on June 21, 2022, exceeding 200. This location should be closely monitored and managed.

Figure 10. Bollworm Moth Trap Catches for Mississippi County (May 31 – June 21, 2022)

The x-axis of the bar graph indicates monitored dates of bollworm trap dates: May 31, June 7, June 14, and June 21, 2022. The y-axis scales from 0 to 250 and indicates the number of moths captured per trap. Colored bars represent the monitored locations: blue, orange, gray, yellow, and black represent locations at Bassett, Osceola, Blytheville, Manila, and NEREC, respectively. 

Monroe County

Bollworm moth trap catches were reported at six out of seven locations in Monroe County on June 17, 2022 (Figure 11). Roe reported the highest collection of trap catches at 250. Brinkley and Clarendon each had between 50 to 100, and Fargo trap catches were at 50. Crossroads and Blackton had under 50 captures reported, and the Holly Grove location reported none.

Figure 11. Bollworm Moth Trap Catches for Monroe County (June 17, 2022)

The x-axis of the bar graph indicates the date bollworm traps were monitored, June 17, 2022. The y-axis scales from 0 to 300 moths and indicates the number of moths captured per trap. Colored bars of blue, orange, gray, yellow, light blue, green, and navy represent Fargo, Brinkley, Roe, Clarendon, Holly Grove, Blackton, and Crossroads, respectively.

Poinsett County

Poinsett County reports of bollworm trap catches indicated that Judd Hill and Bay are particular locations of concern. On June 16, 2022, these locations captured over 350 and nearing 250 bollworm moths, respectively (Figure 12). Weona trap captures approached 100, and the count at Tyronza was approximately 25. No bollworm moth trap catches were reported at the Weiner location for the monitored data date.

Figure 12. Bollworm Moth Trap Catches for Poinsett County (June 16, 2022)

The x-axis of the bar graph indicates the date bollworm traps were monitored, June 16, 2022. The y-axis is scaled from 0 to 400 and indicates the number of moths captured per trap. Colored bars of blue, orange, gray, yellow, light blue, and green represent Weona, Tyronza, Judd Hill, Fisher, Weiner, and Bay, respectively.

White County

Bollworm moth trap catches were reported at three locations in White County for the data period of June 5 – 12, 2022 (Figure 13). The Cain location had the most bollworm moth activity, with approximately 65 trap catches reported on June 12. The Feather location reported 20 to 40 captures during the reporting period, and the Peacock location began to see an uptake in moth activity.

Figure 13. Bollworm Moth Trap Catches for White County (June 5 – 12, 2022)

The x-axis of the bar graph indicates the dates bollworm traps were monitored: June 5 and 12, 2022. The y-axis scales from 0 to 70 and indicates the number of moths captured per trap. Colored bars of blue, orange, and gray represent locations Cain, Feather, and Peacock, respectively. 

Woodruff County

Bollworm moth trap catches were reported at five locations in Woodruff County for the data period of June 9 – 23, 2022 (Figure 14). All monitored locations are areas of concern, with Augusta being the exception. The Deview location reported the highest bollworm moth activity with over 950 trap catches at the close of the data period. Captures at Cotton Plant, Revel, and McCrory indicated high bollworm moth trap catches at approximately 700, 600, and 250, respectively.

Figure 14. Bollworm Moth Trap Catches for Woodruff County (June 9 – 23, 2022)

The x-axis of the bar graph indicates monitored bollworm trap dates: June 9, 16, and 23, 2022. The y-axis scales from 0 to 1,000 and indicates the number of moths captured per trap. Colored bars blue, orange, gray, yellow, and black represent the locations Cotton Plant, Deview, McCrory, Augusta, and Revel, respectively.