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.
Field locations for seed potatoes, tablestock potatoes, and nursery growers who export were sampled from September through November 2019. A total of 33 soil samples were taken from 12 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. Results are pending.
During the 2019 season, NDA inspected 38 Christmas trees dealer locations in 16 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.
Trees showing signs of an EAB infestation were found in Lancaster County in May 2019. This was confirmed by NDA. This find did not affect the existing quarantine for Cass, Dodge, Douglas, Lancaster, Otoe, Sarpy, Saunders, and Washington counties.
NDA continues to inspect nursery stock for insect and disease problems, including EAB. NDA Inspectors also check for labeling of place of origin on nursery stock, as required by the Nebraska Plant Protection and Plant Pest Act, to ensure federal and state quarantines are being followed. NDA works 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 129 firewood dealers in 24 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. Two Withdrawal-From-Distribution Orders were issued for 31 bundles of firewood where origin was unknown.
Outreach is also part of this effort. For more information, please see the Education and Outreach Events section.
Firewood surveys are also conducted as part of Nebraska’s gypsy moth prevention efforts. For details, see Firewood Dealer Quarantine Compliance Inspections above.
In 2019, a total of 140 JB traps (112 detection and 28 certification traps) were set in 27 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. 2019. A total of 37 traps were positive, in 13 counties.
After the 2019 trapping season, NDA declared four more counties as being infested with JB (Red): Furnas, Kearney, Scottsbluff, and Thomas. Prior to 2019, Adams, Buffalo, Burt, Butler, Cass, Clay, Colfax, Cuming, Dakota, Dawson, Dodge, Douglas, Fillmore, Gage, Hall, Hamilton, Howard, Jefferson, Johnson, Lancaster, Lincoln, Madison, Merrick, Nance, Nemaha, Otoe, Pawnee, Phelps, Pierce, Platte, Polk, Richardson, Saline, Sarpy, Saunders, Seward, Thayer, Thurston, Washington, Wayne, and York were already listed as infested ((Green).
Karnal Bunt sampling occurred in July 2019. A total of 41, four-pound wheat samples were pulled in 20 counties, based on the 2018 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 2018 with an additional 102 traps scheduled to be set in January 2019 in 11 additional counties. Traps will be monitored monthly, for 90 days in the winter of 2019 with survey concluding by the end of April 2019. No traps were positive for Khapra beetle. Khapra beetle surveys for 2020 began in December of 2019.
This detection survey will gather data to determine the presence or absence of the following oak insects not known to occur in Nebraska: oak ambrosia beetle (Platypus quercivorus), pink gypsy moth (aka rosy moth - Lymantria mathura), variegated golden tortrix (Archips xylosteanus), and oak processionary moth (Thaumetopoea processionea). The survey involves two different trap types: multi-funnel traps and wing traps. Traps were placed in May and June 2019, and monitored throughout the summer. A total of 15 sites in 9 counties were surveyed for these pests, with a total of 60 traps set. All traps were negative.
NDA participated in the National PCN survey from September through November 2019. 2,837 – 5-pound soil samples were collected, from 7 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 2019, NDA inspectors conducted compliance inspections at 68 seed potato dealer locations in 20 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.
From May-September 2019, NDA conducted 93 visual surveys in 25 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 70 of the 93 locations surveyed had ToH present. SLF was not detected at any location surveyed this year.
In 2019, NDA trapped for walnut twig beetle at a total of 17 sites in 12 counties. Each trapping site consisted of three mulit-funnel traps in various locations for a total of 54 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. Two traps at one location in Scottsbluff County (Red) were positive for walnut twig beetle. In 2020, NDA will conduct surveys in Scottsbluff County for trees infected with Geosmithia morbida, the causative agent of Thousand Cankers Disease. There is currently no quarantine or export restrictions in place for this pest, pending the detection of infected trees.
In 2019, NDA trapped for VLB at 16 sites in 14 counties from June- August 2019. Each trap site consisted of 3-6 cross-vein panel traps totaling 51 traps in the state. Traps were serviced every two weeks. VLB were collected from traps in Keith, Douglas, and Cass counties ((Red) in 2019. These collections have not changed any existing nor created any new quarantines or export restrictions within the state.