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Extension Entomology

Month: October 2020

SOYBEAN – bean leaf beetle

–by Dr. Jeff Whitworth

Most soybeans have developed well past the point of being susceptible to soybean pests (excluding lodging due to Dectes stem girdling). However, there are still some late-planted fields that have pests feeding on the pods. See (fig 3) of grasshopper feeding bite site and bean leaf beetle chewed hole. However, grasshoppers should be dying soon and thus not causing much actual damage. The bean leaf beetles will soon be migrating from these soybean fields to overwintering sites.

Figure 3. Soybean pod damage by grasshopper and bean leaf beetle (Cayden Wyckoff)

ALFALFA – potato leafhoppers

–by Dr. Jeff Whitworth

Alfalfa should probably still be monitored for pests. Every alfalfa field sampled throughout south central and north central Kansas from 8-13 October had significant infestations of potato leafhoppers (see fig 1). The treatment threshold for potato leafhoppers is variable as the economics of hay production is so dynamic depending upon the end use of the hay. However, potato leafhoppers can stress alfalfa in 2 ways–removing plant fluids due to their feeding with the simultaneous injection of a toxin (see fig 2 of “hopper burn”). These two factors may stress alfalfa at any time of the year, but especially this time of year (especially during this dry period) because it may hamper the plant’s ability to prepare for overwintering. One positive note, however, all potato leafhoppers observed in the last 10 days were adults; so hopefully, they will be migrating out of Kansas for overwintering sites in the southern U.S.  All fields sampled had not been swathed, so if they are cut soon this should also help eliminate any leafhopper problems.

Figure 1. Potato Leafhoppers (Cayden Wyckoff)

 

Figure 2.  “Hopper Burn on alfalfa (Cayden Wyckoff)

 

 

Commercial Applicator Recertification Training Changes for 2020

–by Frannie Miller

Each year in the fall, I plan trainings and look forward to seeing applicators from across the state as they attend these commercial recertification-training programs. This year will look a lot different in terms of training opportunities. Due to the ever presence of Covid, the Kansas State Pesticide Safety Program will be hosting virtual training opportunities through zoom. This will allow the applicator to obtain pest management credits from the safety of his or her home or office. I have heard from some applicators that feel they are technologically challenged, but don’t let that keep you from trying a new way of learning. The team is here to help you every step of the way!

The Kansas State Pesticide Safety Program is hosting training on the following dates:

  • October 20 – 21 (9:20 a.m. – 11:30 a.m.) (1:20 p.m. -3:30 p.m.) Right-of-Way, Industrial Weed, and Noxious Weed Training (Category 6, 7C, & 9A)
  • November 2 (12:30 p.m. – 5:15 p.m.) and November 3 (8:30 a.m. – 11:30 a.m. Stored Product Pests and Seed Treatment (Category 7B & 4)
  • November 4 (9:20 a.m. – 11:30 a.m.) Ornamental, Turf and Interiorscape (Category 3A, 3B, & 3C)
  • November 9 (8:30 a.m. – 5:00 p.m.) Ag Plant (Category 1A)
  • November 10 (8:30 a.m. – 5:00 p.m.) Structural and Public Health (Category 7D, 7E & 8)
  • November 10 (12:00 p.m. – 1:00 p.m.) Core Hour
  • November 12 (8:30 a.m. – 5:00 p.m.) Wood Destroying and Wood Preservation (Category 7A & 7F)
  • November 12 (12:00 p.m. – 1:00 p.m.) Core Hour
  • November 13 (8:30 a.m. – 5:00 p.m.) Forest Pest, Ornamental, Turf and Interiorscape (Category 2, 3A, 3B & 3C)

Flyers containing the registration information can be found on the Pesticide Safety and IPM webpage at: https://www.ksre.k-state.edu/pesticides-ipm/commercial-applicator.html. If you use Facebook, you may want to consider liking the Kansas State Pesticide Safety and IPM program page, which can be found at: https://www.facebook.com/KSRE-Pesticide-Safety-and-Integrated-Pest-Management-Program-109039044075447.

Other groups or associations may be hosting other training opportunities. A complete list can be found at: https://portal.kda.ks.gov/PAF/PafTraining/TrainingEventList.

If you don’t remember how many credits you have or need, you can look up your training status at: https://portal.kda.ks.gov/paf/pafapplicator/login/

If you have further questions, regarding how this training will be conducted contact Frannie Miller at (620)241-1523 or e-mail fmiller@ksu.edu.

Volunteer Wheat

–by Dr. Jeff Whitworth

 

Much wheat has been planted but much is still to be planted. Please remember that volunteer wheat (see fig 4) needs to be dead at least 3 weeks prior to planted wheat germinating. This really helps mitigate wheat pests that may be utilizing this volunteer wheat as a “green bridge”– just waiting to move from these plants to infest the germinating new plants.

Figure 4 Volunteer Wheat (Cayden Wyckoff)

 

Sorghum

–by Dr. Jeff Whitworth

 

Most sorghum throughout south and north central Kansas has developed past the stage that might be susceptible to infestations by sorghum headworms (susceptible stage is generally considered to be between flowering and soft dough). However, some late-planted fields may still be vulnerable to headworm infestations (see Fig 1) but fortunately, infestations remain very low.

 

Figure 1 Headworm (found 8 Oct 2020) (Cayden Wyckoff)

Sugarcane aphids are still migrating into the state, and probably will until we get much cooler temperatures and fewer south winds. Fortunately, beneficials (see fig 2 of pink spotted lady beetle) are still plentiful in most sorghum fields. All sugarcane aphids detected in the last 10 days on later planted sorghum had only small, scattered colonies of sugarcane aphids (see fig 3).

Figure 2 Pink spotted lady beetle (Cayden Wyckoff)

Figure 3 Sugarcane aphid colonies (Cayden Wyckoff)

 

Large Milkweed Bug

–by Dr. Raymond Cloyd

We are receiving inquiries regarding the large milkweed bug, Oncopeltus fasciatus, nymphs and adults feeding on the seed pods of milkweed (Asclepias spp) plants (Figure 1).

Figure 1. Large Milkweed Bug Adults And Nymphs Feeding On Milkwee Seed Pod (Raymond Cloyd, KSU)

Large milkweed bug adults are 9/16 to 5/8 inches (10 to 18 mm) in length, with black and orange markings on the body (Figure 2).

 

 

Figure 2. Large Milkweed Bug Adult (Raymond Cloyd, KSU)

There are five nymphal instars before becoming adults. Females lay eggs on milkweed seed pods or in crevices between the seed pods. Females can lay up to 30 eggs per day and approximately 2,000 over her lifetime, which is about one month in the summer. The adults contain toxic compounds that are obtained from the plant fluids during feeding, which protects them from predators. Large milkweed bugs cause minimal damage to milkweed plants and are present for a short period. Large milkweed bugs overwinter as adults. There may be one to several generations per year in Kansas