The Entomology Program conducts plant pest surveys (insects, plant diseases, and nematodes). Plant pest surveys can be conducted by periodic visual surveys, sampling, or regular detection trapping programs. Surveys are conducted to determine if a particular pest exists in an area (example, in a county), and if found, how extensive the infestation is. Surveys are also needed to determine the feasibility of eradication, areas where eradication treatments need to be applied, and areas where quarantine measures need to be applied.
Plant pest survey data is needed in order to facilitate exports. Presence or absence data is important. Plant pests that may hinder or restrict plant and plant product exports should be surveyed. Laboratory diagnosis of the plant pests is crucial. This data is needed to document pest-free areas. Pest management areas will also be gained from survey data. Coordination of a statewide survey is important to the plant industry of Nebraska.
Regionalization provides for the certification of plants and plant products on a regional basis. This regional approach allows for the establishment of pest-free areas.
In 2020, NDA began a survey for agricultural pests potentially introduced through extensive flooding in 2019 and subsequent supplies shipped to Nebraska from other states to help farmers in need. Some of these states have established populations of invasive species we don’t want introduced in the state. Each site consisted of two bucket traps, a plastic delta trap, wing trap, pyramid trap, and visual surveys for select pests. All traps and visual surveys were negative.
Field locations for seed potatoes, tablestock potatoes, and nursery growers who export were sampled from September through November 2020. A total of 29 soil samples were taken from 11 counties across Nebraska. Samples were submitted for analysis to the UNL Plant Pathology Department for the presence of quarantine and export significant nematodes including: potato rot (Ditylenchus destructor); potato cyst (Globodera pallida, G. rostochiensis); soybean cyst nematode (Heterodera glycines); root knot nematodes (Meloidogyne chitwoodi, M. hapla, M. javanica); and other plant parasitic nematode genera. Dr. Tom Powers, UNL nematologist, and his staff conduct morphological and molecular diagnostics of all adult and juvenile nematodes found in the soil samples. The identification of plant parasitic nematodes helps to establish and maintain pest-free areas for the export of plants and plant products. All samples were negative for quarantine pests.
During the 2020 season, NDA inspected 131 Christmas trees dealer locations in 42 counties across the state. Inspections occurred in November and December to verify compliance with the federal Gypsy Moth and Pine Shoot beetle quarantines. Inspectors confirm compliance through paperwork review and physical inspection of the trees. No violations were found.
In 2020, NDA began a survey of commercial nursey stock locations. Each site consisted of two bucket traps, wing trap, paper delta trap and visual surveys for select pests. All traps and visual surveys were negative.
Trees showing signs of an EAB infestation were investigated in Buffalo and Washington counties. An adult beetle was collected from a suspect tree in Buffalo County.
In December 2020, the USDA officially deregulated EAB and has lifted the federal quarantine. NDA has no plans to enact a state quarantine for EAB but will continues to inspect nursery stock for insect and disease problems, including EAB. NDA will continue to work to educate the nursery industry about this potential threat to ash trees in Nebraska, through outreach programs. NDA has developed EAB outreach materials, which continue to be distributed at various industry meetings and conferences, and are also available on the NDA web site.
NDA inspectors inspect firewood dealers across the state to confirm compliance with state and federal quarantines that regulate the movement of firewood. A total of 197 firewood dealers in 47 counties were inspected to verify compliance with the Federal Gypsy moth, EAB, and Asian Longhorn Beetle quarantines and the Nebraska Thousand Cankers Disease of Walnut and Nebraska EAB quarantines. While most of the wood was of Nebraska origin, wood was also found to have originated in other states and countries, including Alabama, Georgia, Illinois, Kentucky, Minnesota, Missouri, New York, North Carolina, Virginia, Wisconsin, and Latvia. One Withdrawal-From-Distribution Order was issued for 14 bundles of firewood where origin was unknown. It was later release for sale after proper documentation was provided.
Outreach is also part of this effort. For more information, please see the Education and Outreach Events section.
In 2020, NDA began a grape commodity survey. A total of 15 locations in 12 counties were surveyed. Each site consisted of a plastic delta trap, wing trap, paper delta trap and visual survey for select species. All traps and visual surveys were negative.
Firewood surveys are also conducted as part of Nebraska’s gypsy moth prevention efforts. For details, see Firewood Dealer Quarantine Compliance Inspections above.
In 2020, a total of 144 JB traps (92 detection and 52 certification traps) were set in 28 counties across the state. Traps are located at airports, state parks, special quarantine compliance areas, and nurseries. Nursery stock distributors in non-infested counties that import balled and burlapped nursery stock are considered high-risk sites and, therefore, trapped individually. The traps were in place from the end of May until October 1. 2020. A total of 49 traps were positive, in 13 counties.
In 2021 Nebraska will be moving to Category 3 status under the Japanese Beetle Harmonization Plan. This change will take Nebraska from Category 2, partially infested, to wholly infested.
After the 2020 trapping season, NDA declared 7 more counties (Boone, Box Butte, Franklin, Garden, Kimball, Nuckolls, and Webster) as being infested with JB. Prior to 2020, Adams, Buffalo, Burt, Butler, Cass, Clay, Colfax, Cuming, Dakota, Dawson, Dodge, Douglas, Fillmore, Furnas, Gage, Hall, Hamilton, Howard, Jefferson, Johnson, Kearney, Lancaster, Lincoln, Madison, Merrick, Nance, Nemaha, Otoe, Pawnee, Phelps, Pierce, Platte, Polk, Richardson, Saline, Sarpy, Saunders, Scottsbluff, Seward, Thayer, Thomas, Thurston, Washington, Wayne, and York were already listed as infested.
Karnal Bunt sampling occurred in July 2020. A total of 24, four-pound wheat samples were pulled in 18 counties, based on the 2020 National Karnal Bunt Survey Protocol. All samples were sent to the National Karnal Bunt Lab in Phoenix, Arizona, for analysis. All samples tested negative for Karnal Bunt.
Federal funding was approved for a Khapra beetle survey in Nebraska for 2019. Six traps were set in one county in December of 2019 with an additional 114 traps set in January 2020 in 11 additional counties. Traps are monitored monthly, for 90 days in the winter of 2020 with survey concluding by the end of April 2020. Travel restrictions and business closures from directed health measures related to COVID-19 delayed or prevented collection of all traps. 15 traps were not recovered due to business not reopening in 2020. None of the 105 traps collected were positive for Khapra beetle. Khapra beetle surveys for 2021 began in December of 2020.
NDA participated in the National PCN survey from September through November 2020. 1,618 – 5-pound soil samples were collected, from 4 counties. Samples were sent to the USDA Idaho Falls PCN laboratory for processing to determine the presence or absence of (Globodera pallida and Globodera rostochiensis). Results are pending.
During early spring of 2020, NDA inspectors conducted compliance inspections at 33 seed potato dealer locations in 11 counties. These inspections were to confirm compliance with Nebraska’s Columbia Root Knot Quarantine, and the Federal Potato Cyst Nematode quarantine. Four violations were found.
Travel restrictions from directed health measures related to COVID-19 limited the scope of this survey. Seed potato compliance inspections have a limited window for inspection in the spring of each year.
From May-December 2020, NDA conducted 139 visual surveys in 28 counties across Nebraska for SLF and Tree of Heaven (ToH), the preferred host of adult SLF. Visual surveys were conducted to determine the presence of SLF or ToH at nurseries, urban greenspaces, roadways, and forested areas across the state. These surveys will be used to record high-risk areas for introduction and establishment of SLF in Nebraska. A total of 75 of the 139 locations surveyed had ToH present. SLF was not detected at any location surveyed this year.
In 2020, NDA trapped for walnut twig beetle at a total of 15 sites in 12 counties. Each trapping site consisted of three mulit-funnel traps in various locations for a total of 48 traps in the state. This survey was very labor intensive. In order to maintain the viability of the sample for accurate ID of the pest, traps were serviced every two weeks. Three traps at two locations in Scottsbluff County were positive for walnut twig beetle. One location was positive in 2019. In 2020, NDA conducted baited branch surveys in Scottsbluff County for trees infected with Geosmithia morbida, the causative agent of Thousand Cankers Disease. There was no activity on the baited branches. There is currently no quarantine or export restrictions in place for this pest, pending the detection of infected trees.
In 2020, NDA trapped for VLB at 15 sites in 13 counties from June- August 2020. Each trap site consisted of 3-6 cross-vein panel traps totaling 45 traps in the state. Traps were serviced every two weeks. VLB were collected from traps in Keith, Douglas, and Cass counties in 2019. VLB were collected from traps in Kearney, Lancaster, Lincoln and Sarpy counties in 2020. These collections have not changed any existing nor created any new quarantines or export restrictions within the state.