ABSTRACT Black walnut, Juglans nigra, an important tree, both economically and culturally, is wid... more ABSTRACT Black walnut, Juglans nigra, an important tree, both economically and culturally, is widely grown and valued for its wood and its nuts. Thousand cankers disease (TCD), caused by the fungus Geosmithia morbida vectored by the walnut twig beetle, Pityopththorus juglandis, was discovered in the native range (Knox County, Tennessee) of black walnut in 2010. TCD has already killed thousands of non-native black walnut trees in the western U.S., and threatens those in its native range, where it also has been documented in North Carolina, Ohio, Pennsylvania, Tennessee, and Virginia. State quarantines have been enacted in all confirmed states to curtail the spread and impact of this deadly disease. Unfortunately, the general public is not aware of the problem, its potential impact, or mitigation efforts. The overall goal of this poster is to describe a regional Outreach Plan titled “Walnut Alert” – this Plan involves the development and implementation of outreach tools and programs (web-based materials, educational displays, pamphlets, posters, fact sheets, technical papers and presentations, workshops, field days, news media outlets, etc.) to inform growers, industry, scientists, regulators, and the general public of the issues surrounding TCD in the native range of black walnut, as well as to train students to be more knowledgeable in the workforce. A well-developed Outreach Plan can educate endusers, consumers, and the general public, resulting in a reduction in the spread of this deadly disease and providing the necessary time to develop appropriate and effective management strategies.
In East Tennessee, three clerid species have been observed feeding on the walnut twig beetle, Pit... more In East Tennessee, three clerid species have been observed feeding on the walnut twig beetle, Pityophthorus juglandis, the vector for Thousand Cankers disease on black walnut. These predators were collected from black walnut and are under evaluation as potential biological control agents for the walnut twig beetle.
Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens... more Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens to significantly diminish populations of Juglans nigra (black walnut) throughout its native range. Two insecticides (imidacloprid, dinotefuran) and one fungicide (potassium phosphite) are under evaluation as potential chemical control agents for P. juglandis and the thousand canker disease.
Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens... more Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens to significantly diminish populations of Juglans nigra (black walnut) throughout its native range. Since little is known about P. juglandis in Tennessee, the flight activity, habitat behavior, and life stages are being evaluated to better understand this pest. Also, two insecticides (imidacloprid, dinotefuran) and one fungicide (potassium phosphite) are under evaluation as potential chemical control agents for P. juglandis and the thousand canker disease. In addition, three clerid species have been discovered in the eastern US that feed on P. juglandis. Tests are underway to determine the impact of clerids’ as biological control agents for P. juglandis.
Black walnut, a valuable economic and environmentally important species, is threatened by thousan... more Black walnut, a valuable economic and environmentally important species, is threatened by thousand cankers disease. Systemic imidacloprid and dinotefuran applications were made to mature black walnut trees to evaluate their translocation and concentration levels in various tissue types including leaf, twig, trunk core, nutmeat, and walnut husk. The metabolism of imidacloprid in plants produces a metabolite, olefin-imidacloprid, which has been documented to have insecticidal properties in other systems. Trunk CoreTect (imidacloprid) soil pellets and a trunk spray of dinotefuran were applied to mature black walnuts in spring 2011. Imidacloprid concentrations were detected in both the lower and upper strata in all tissue types tested and progressively increased through month 12 post-treatment in twig and leaf tissue. Olefin-imidacloprid was detected in the nutmeat and walnut husk. Dinotefuran was only detected in the first sampling period and was found in low concentration levels in leaf and twig tissue types, and was not detected in the trunk, nutmeat or the walnut husk.
Black walnut, Juglans nigra, is an important tree, both economically and culturally, and it is wi... more Black walnut, Juglans nigra, is an important tree, both economically and culturally, and it is widely grown and valued for its wood and its nuts. Thousand cankers disease (TCD), caused primarily by the fungus Geosmithia morbida vectored by the walnut twig beetle, Pityophthorus juglandis, was discovered in the native range of black walnut in 2010. TCD is a devastating threat to black walnut and has the potential to lead to the extinction of this important tree species if effective management plans are not developed and implemented quickly. In western states, TCD has killed thousands of non-native black walnut trees, and in Tennessee, which represents the first documentation of this beetle and its associated pathogen, G. morbida, in the native range of black walnut, tree mortality and decline have already been observed. TCD has been documented in seven counties in Tennessee, and this disease was found in Pennsylvania and Virginia in 2011 and in North Carolina in 2012. State quarantine...
ABSTRACT Black walnut, Juglans nigra, an important tree, both economically and culturally, is wid... more ABSTRACT Black walnut, Juglans nigra, an important tree, both economically and culturally, is widely grown and valued for its wood and its nuts. Thousand cankers disease (TCD), caused by the fungus Geosmithia morbida vectored by the walnut twig beetle, Pityopththorus juglandis, was discovered in the native range (Knox County, Tennessee) of black walnut in 2010. TCD has already killed thousands of non-native black walnut trees in the western U.S., and threatens those in its native range, where it also has been documented in North Carolina, Ohio, Pennsylvania, Tennessee, and Virginia. State quarantines have been enacted in all confirmed states to curtail the spread and impact of this deadly disease. Unfortunately, the general public is not aware of the problem, its potential impact, or mitigation efforts. The overall goal of this poster is to describe a regional Outreach Plan titled “Walnut Alert” – this Plan involves the development and implementation of outreach tools and programs (web-based materials, educational displays, pamphlets, posters, fact sheets, technical papers and presentations, workshops, field days, news media outlets, etc.) to inform growers, industry, scientists, regulators, and the general public of the issues surrounding TCD in the native range of black walnut, as well as to train students to be more knowledgeable in the workforce. A well-developed Outreach Plan can educate endusers, consumers, and the general public, resulting in a reduction in the spread of this deadly disease and providing the necessary time to develop appropriate and effective management strategies.
In East Tennessee, three clerid species have been observed feeding on the walnut twig beetle, Pit... more In East Tennessee, three clerid species have been observed feeding on the walnut twig beetle, Pityophthorus juglandis, the vector for Thousand Cankers disease on black walnut. These predators were collected from black walnut and are under evaluation as potential biological control agents for the walnut twig beetle.
Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens... more Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens to significantly diminish populations of Juglans nigra (black walnut) throughout its native range. Two insecticides (imidacloprid, dinotefuran) and one fungicide (potassium phosphite) are under evaluation as potential chemical control agents for P. juglandis and the thousand canker disease.
Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens... more Pityophthorus juglandis, a newly discovered invasive pest species in eastern Tennessee, threatens to significantly diminish populations of Juglans nigra (black walnut) throughout its native range. Since little is known about P. juglandis in Tennessee, the flight activity, habitat behavior, and life stages are being evaluated to better understand this pest. Also, two insecticides (imidacloprid, dinotefuran) and one fungicide (potassium phosphite) are under evaluation as potential chemical control agents for P. juglandis and the thousand canker disease. In addition, three clerid species have been discovered in the eastern US that feed on P. juglandis. Tests are underway to determine the impact of clerids’ as biological control agents for P. juglandis.
Black walnut, a valuable economic and environmentally important species, is threatened by thousan... more Black walnut, a valuable economic and environmentally important species, is threatened by thousand cankers disease. Systemic imidacloprid and dinotefuran applications were made to mature black walnut trees to evaluate their translocation and concentration levels in various tissue types including leaf, twig, trunk core, nutmeat, and walnut husk. The metabolism of imidacloprid in plants produces a metabolite, olefin-imidacloprid, which has been documented to have insecticidal properties in other systems. Trunk CoreTect (imidacloprid) soil pellets and a trunk spray of dinotefuran were applied to mature black walnuts in spring 2011. Imidacloprid concentrations were detected in both the lower and upper strata in all tissue types tested and progressively increased through month 12 post-treatment in twig and leaf tissue. Olefin-imidacloprid was detected in the nutmeat and walnut husk. Dinotefuran was only detected in the first sampling period and was found in low concentration levels in leaf and twig tissue types, and was not detected in the trunk, nutmeat or the walnut husk.
Black walnut, Juglans nigra, is an important tree, both economically and culturally, and it is wi... more Black walnut, Juglans nigra, is an important tree, both economically and culturally, and it is widely grown and valued for its wood and its nuts. Thousand cankers disease (TCD), caused primarily by the fungus Geosmithia morbida vectored by the walnut twig beetle, Pityophthorus juglandis, was discovered in the native range of black walnut in 2010. TCD is a devastating threat to black walnut and has the potential to lead to the extinction of this important tree species if effective management plans are not developed and implemented quickly. In western states, TCD has killed thousands of non-native black walnut trees, and in Tennessee, which represents the first documentation of this beetle and its associated pathogen, G. morbida, in the native range of black walnut, tree mortality and decline have already been observed. TCD has been documented in seven counties in Tennessee, and this disease was found in Pennsylvania and Virginia in 2011 and in North Carolina in 2012. State quarantine...
Uploads
Papers by Katheryne Nix