The Entomology Program, Bureau of Plant Industry, 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 will be sampled in September, October, and November. In 2016, a total of 27 soil samples were taken in 11 counties across Nebraska. Samples were analyzed by 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 conducted 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. The documentation of species distribution will exhibit compliance to certification of potatoes. Results are pending.
During the 2016 season, NDA staff inspected Christmas trees at 78 dealers in 17 counties. Inspections took place 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.
Beginning in May 2016, NDA inspectors set traps and conducted visual surveys and sampling as part of the corn commodity survey. Targeted pests included old world bollworm (Helicoverpa armigera), brown stripe downy mildew (Sclerophthora rayssiae var. zeae), Philippine downy mildew (Peronosclerospora philippinensis), java downy mildew (Peronosclerospora maydis), tar spot (Phyllachora maydis), and Xanthomonas. In 2016, surveys of 64 corn fields were conducted in 14 counties. Thirty-nine fields tested positive for disease and all counties in surveyed were positive. The most prevalent disease detected was bacterial blight.
NDA inspectors also set traps and conducted visual surveys for old world bollworm. Ten traps were set and all results were negative.
As part of a national survey, NDA set and monitored 38 traps in five counties at high-risk areas, such as state parks and rest stops. All traps were negative. NDA did, however, confirm the first emerald ash borer (EAB) find in Douglas County in Spring, 2016. There was also a non-survey EAB find in Cass County. NDA issued a quarantine for Douglas, Sarpy, Cass Washington and Dodge counties prohibiting ash nursery stock from leaving the quarantine area. The quarantine also regulates the movement of hardwood firewood and mulch, ash timber products and green waste out of the quarantined areas to assist in the prevention of human-driven spread of EAB to uninfested areas.
NDA continues to inspect nursery stock for insect and disease problems, including EAB. Particular attention is given to ash stock entering the state. NDA Inspectors 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 continues 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. Additional information on EAB, including quarantine information, can be found on our EAB page.
NDA inspectors have inspected firewood dealers across the state to collect data on the distribution of firewood in Nebraska, as well as the origins of the firewood. A total of 78 firewood dealers in 17 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 quarantine. While most of the wood was of Nebraska origin, wood was also found to have originated in eleven other states or countries, including Alabama, Georgia, Illinois, Kentucky, Minnesota, Missouri, New York, North Carolina, Virginia, Wisconsin, and Latvia. Three Withdrawal-From-Distribution Orders were issued for 56 bundles of firewood that originated within the Nebraska quarantine area and were found outside of the quarantine.
A total of 566 gypsy moth traps were set in 2016. All were detection traps. Traps were set in 37 counties across the state. All traps 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 2016, a total of 128 JB traps were set in non-infested counties. Fifty-eight traps were set in known infested counties. 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 sights and, therefore, trapped individually. The traps were in place from the end of May until October 1.
After the 2016 trapping season, NDA declared three more counties as being infested with JB: Clay, Colfax, and Merrick. Prior to 2016, Adams, Buffalo, Burt, Cass, Dakota, Dawson, Dodge, Douglas, Gage, Hall, Hamilton, Jefferson, Lancaster, Lincoln, Madison, Merrick, Otoe, Phelps, Platte, Saline, Sarpy, Saunders, Seward, Thayer, Washington, Wayne, and York were already listed as infested.
Soil sampling for JB grubs was conducted in 2016, at select firms in known infested counties, where JB populations had previously been confirmed via trapping. Firms were selected based on several factors, including level of infestation, nursery production methods, and desire to ship out of state. A total of 325 soil samples were collected on over 371 acres from five firms in five counties. No JB grubs were found.
Karnal Bunt sampling occurred in June and July 2016. A total of 68, four-pound wheat samples were pulled in 27 counties, based on the 2016 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.
In 2016, a total of 120 Khapra beetle traps were set at 40 sites in 5 counties. Traps were screened for Khapra beetles every 30 days during lure replacement and remained in place for 90 days. All traps were negative for Khapra beetle.
NDA participated in the National PCN survey from September through early November 2016. Upon completion, 1, 498 five-pound soil samples were collected from potato fields in four potato producing counties. All samples were sent to the USDA Idaho Falls PCN laboratory for PCN (Globodera pallida and Globodera rostochiensis). Results are pending.
During early spring of 2016, NDA inspectors conducted compliance inspections at 103 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. Seven violations were found.
In June 2016, NDA inspectors set various traps, collected samples, conducted sweep net sampling, and conducted visual surveys for numerous pests as part of the small grain commodity survey. These pests included wheat bug (Nysius huttoni), curcurbit beetle (Diabrotica speciose), maritime garden snail (Cernuella virgata), conical snails (Cochlicella spp), dwarf-bunt (Tilletia controversa), wheat flag smut (Urocystis agropyri), black stem rust (Puccinia graminis), Philippine downy mildew (Peronosclerospora philippinensis), cereal cyst nematode (Heterodera filipjevi), Mediterranean cereal cyst nematode (Heterodera latipons), British root-knot nematode (Meloidogyne artiellia), and rust susceptible barberry plants. Visual survey and soil sampling was conducted in 87 sites from 22 counties. All results were negative.
In 2016, NDA trapped for walnut twig beetle at a total of 17 sites in 11 counties. Each trapping site consisted of 3-6 funnel traps in various locations for a total of 56 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. All traps were negative.