Progress 10/01/07 to 09/30/10
Outputs
OUTPUTS: Findings from this research project were presented at the following scientific meetings, workshops, and/or short courses: 1. Joint Annual Meeting of the Society for Range Management and Weed Science Society of America. Feb. 7-11, 2010 Denver, CO; 2. Annual Meeting of the Entomological Society of America, Indianapolis, IN. Dec. 13-16, 2010; 3. 64th Annual Meeting of the Northeastern Weed Science Society, Cambridge, MA Jan. 4-7, 2010; 4. Cornell Cooperative Extension In-service Agriculture and Food Systems Program. Co-sponsored by the NY Invasive Species Clearinghouse and NY Invasive Species Research Institute. Ithaca, NY. [Nov. 11, 2009. 5. Northeastern Weed Science Society (NEWSS) Noxious and Invasive Vegetation Management Short Course. Mount Gretna, PA. Sept. 21-24, 2009. 6. Swallow-wort Control at Wehle State Park Worksho, NY State Office of Parks, Recreation, and Historic Preservation (OPRHP) in Albany, NY on May 12, 2009; 7. Odum Conference in Rensselaerville, NY. April 30-May1, 2009; 8. Town of Ithaca Conservation Board April Meeting. Ithaca, NY. April 2, 2009. PARTICIPANTS: Dr. Lindsey R. Milbrath, USDA-ARS, Ithaca, NY 14853; Co-PI - Dr. Charles L. Mohler, Department of Crop and Soil Sciences, Cornell University, Ithaca NY 14853. A total of four undergraduate students and a part-time research assistant worked directly on this project both during the growing season and in the off season. TARGET AUDIENCES: Relevant findings from this research were presented at scientific meetings as well as cooperative extension meetings to inform participants of the relevance of the research for long term sustainbale management of the invasive swallow-wort species. Undegraduate students involved in the project were afforded an opportunity to work directly with trained weed scientists and entomologists and were exposed to the design and execution of multi-season field-based experiments. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The objectives of this research were to determine the effects of multiple seasons of above-ground tissue removal on the: (1) survival, (2) growth, and (3) reproduction of mature pale and black swallow-wort plants under common garden field conditions. Both cutting and artificial defoliation will be used, as well as different frequencies of tissue removal. This field experiment was initiated in spring 2008 and the 2009 growing season was the first where data were collected. To summarize, this experiment is a completely randomized design consisting of two swallowwort species (black (BSW) and pale (PSW) swallowwort), eight foliar manipulations (non-defoliated control; stems clipped once, twice or four times; 50 percent defoliation once or twice; 100 percent defoliation once or twice), and four harvest dates. Although findings from this research reflect the first two years of data collection for this project, it is anticipated that the project will continue for at least several more years to assess longer term effects of defoliation.Pale and black swallow-wort display a high tolerance to above-ground tissue loss in high-light environments, whether by artificial defoliation or clipping (a surrogate for mowing). Four clippings per season was the only type of damage that consistently reduced most, but not all, reproductive and growth parameters, a severe mechanical management approach not currently practiced. Even after two years, 100% defoliation twice per season (simulating a bivoltine defoliator) did not significantly reduce swallow-wort performance, and some damage treatments of lesser severity stimulated reproduction. The potential efficacy of a defoliating insect against field populations of swallow-worts appears questionable. However, it is not uncommon that several seasons of damage are needed before perennial species, such as swallow-worts, begin to decline in vigor. We will continue to track plant performance over the next several years.
Publications
- Blanchard, M.L., J.N. Barney, K.M. Averill, C.L. Mohler, and A. DiTommaso. 2010. Does polyembryony confer a competitive advantage to the invasive perennial vine Vincetoxicum rossicum (Apocynaceae) American Journal of Botany 97(2):251-260.
- Ho, M., K. Averill, C. Mohler and A. DiTommaso. 2010. Biomass allocation of pale and black swallow-wort (Vincetoxicum rossicum and V. nigrum) in contrasting competitive environments and water availabilities. Abstracts from the Joint Annual Meeting of the Society for Range Management and Weed Science Society of America. February 7-11, Denver, CO. O-346.
- Little, N., S. Morse, A. DiTommaso, and L. Milbrath. 2010. Mapping the current and projected ranges of two swallow-wort invasive vines. In: Armel, G.R. (ed.) Proceedings of the 64th Annual Meeting of the Northeastern Weed Science Society, 64:54.
- Milbrath, L.R., J. Biazzo, A.R. Davis, A. DiTommaso, and K.M. Averill. 2009. Matrix population models to guide swallow-wort (Vincetoxicum spp.) biological control. Poster no. D0221. Annual Meeting of the Entomological Society of America, Indianapolis, IN. December 13-16.
|
Progress 10/01/08 to 09/30/09
Outputs
OUTPUTS: Findings from this ongoing research project were presented at the following scientific meetings and/or workshops: 1. Swallow-wort Control at Wehle State Park Workshop, NY State Office of Parks, Recreation, and Historic Preservation (OPRHP) in Albany, NY in May 2009. 2. 50th Annual Meeting of the Weed Science Society of America in Orlando, FL in February 2009. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This field experiment was initiated in spring 2008 and the 2009 growing season was the first where data were collected and these are currently being analyzed. To summarize, this experiment is a completely randomized design consisting of two swallowwort species (black (BSW) and pale (PSW) swallowwort), eight foliar manipulations (non-defoliated control; stems clipped once, twice or four times; 50 percent defoliation once or twice; 100 percent defoliation once or twice), and four harvest dates. Each treatment combination was replicated five times for a total of 320 experimental units. Rootstocks of BSW and PSW were collected from the field in fall 2007. BSW was collected from a densely infested site at Bear Mountain State Park, Rockland Co., NY, and PSW was collected from a densely infested property near Elbridge, Onondaga Co., NY. The rootstocks were washed of soil and stored in moist vermiculite at 4 C until early spring 2008. Following cold storage, rootstocks were weighed to determine initial fresh biomass. Rootstocks were planted every 2-m (within and between rows) into a common garden field setting in Ithaca, NY. To reduce weed competition within rows, landscape cloth (90-cm wide) was secured along the length of each row and 10 x 10 cm holes were cut out around each swallow-wort plant. No treatments were imposed during the 2008 growing season to allow swallow-wort plants to reestablish root systems. Plants will be left undisturbed (control), receive 50 or 100 percent defoliation once or twice during the season, or have their stems clipped once, twice or four times during the season. Plants will be defoliated or clipped in late May (4x clipped), late June (1x, 2x and 4x clipped; 2x defoliated), late July (2x and 4x clipped, 1x and 2x defoliated), and late August (4x clipped). Plants will be defoliated by removing 50 or 100 percent of the leaves and all stem tips whereas clipping treatments will involve cutting the stems to a height of 8 cm. Plants will be assessed yearly prior to the first defoliation or clipping for flowering, stem number and stem length, and at the end of the growing season for mortality, maximum stem length, and number of stems, axillary branches and follicles. Follicles will be collected at maturity but prior to seed dispersal and the number of seeds per plant estimated by counting seeds from a sub-sample of follicles. A subset of plants will be destructively harvested in October for biomass in the second, third, fifth and seventh year of the experiment, corresponding to one, two, four and six successive years of damage. Biomass will be separated into follicle, other aboveground tissue (stems and leaves), and root fractions. The follicle, stem-leaf, and root fractions will be dried at 65 C for at least 7 d and weighed for dry mass. Root-shoot ratios will be calculated. Survival data will be analyzed by log-linear analysis of (truncated) survival times. Stem length, and the number of stems, axillary branches, follicles, and seed produced will be analyzed by a repeated measures analysis of variance. Biomass, the number of crown buds, and root-shoot ratios will be analyzed by analysis of variance.
Publications
- Barney, J.N., T.W. Whitlow, and A. DiTommaso. 2009. Evolution of an invasive phenotype: shift to belowground dominance and enhanced competitive ability in the introduced range. Plant Ecology 202(2):275-284.
- Douglass, C.H., L.A. Weston, and A. DiTommaso. 2009. Black and Pale Swallow-wort (Vincetoxicum nigrum and V. rossicum): The Biology and Ecology of Two Perennial, Exotic and Invasive Vines. Chapter 13. In: Management of Invasive Weeds. Inderjit [ed.], Springer Science + Business Media B.V.,The Netherlands. pp. 261-276.
- DiTommaso, A., S.H. Morris, and A.A. Agrawal. 2009. Grazing by white-tailed deer alters weed seedbank composition in old-fields. Weed Science Society of America Abstracts. No. 39. Weed Science Society of America, Lawrence, KS. (Feb. 2009).
|
Progress 10/01/07 to 09/30/08
Outputs
OUTPUTS: No outputs are reported since this field project was initiated in spring 2008. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
This experiment was initiated in spring 2008 and is a completely randomized design consisting of two swallowwort species (black (BSW) and pale (PSW) swallowwort), eight foliar manipulations (non-defoliated control; stems clipped once, twice or four times; 50 percent defoliation once or twice; 100 percent defoliation once or twice), and four harvest dates. Each treatment combination was replicated five times for a total of 320 experimental units. Rootstocks of BSW and PSW were collected from the field in fall 2007. BSW was collected from a densely infested site at Bear Mountain State Park, Rockland Co., NY, and PSW was collected from a densely infested property near Elbridge, Onondaga Co., NY. The rootstocks were washed of soil and stored in moist vermiculite at 4 C until early spring 2008. Following cold storage, rootstocks were weighed to determine initial fresh biomass. Rootstocks were planted every 2-m (within and between rows) into a common garden field setting in Ithaca, NY. To reduce weed competition within rows, landscape cloth (90-cm wide) was secured along the length of each row and 10 x 10 cm holes were cut out around each swallow-wort plant. Grass was seeded into the alleyways to suppress weeds and prevent soil erosion. No treatments were imposed during the 2008 growing season to allow swallow-wort plants to reestablish root systems. Removal of aboveground biomass will commence during the 2009 growing season. Plants will be left undisturbed (control), receive 50 or 100 percent defoliation once or twice during the season, or have their stems clipped once, twice or four times during the season. Plants will be defoliated or clipped in late May (4x clipped), late June (1x, 2x and 4x clipped; 2x defoliated), late July (2x and 4x clipped, 1x and 2x defoliated), and late August (4x clipped). Plants will be defoliated by removing 50 or 100 percent of the leaves and all stem tips whereas clipping treatments will involve cutting the stems to a height of 8 cm. Plants will be assessed yearly prior to the first defoliation or clipping for flowering, stem number and stem length, and at the end of the growing season for mortality, maximum stem length, and number of stems, axillary branches and follicles. Follicles will be collected at maturity but prior to seed dispersal and the number of seeds per plant estimated by counting seeds from a sub-sample of follicles. A subset of plants will be destructively harvested in October for biomass in the second, third, fifth and seventh year of the experiment, corresponding to one, two, four and six successive years of damage. Biomass will be separated into follicle, other aboveground tissue (stems and leaves), and root fractions. The follicle, stem-leaf, and root fractions will be dried at 65 C for at least 7 d and weighed for dry mass. Root-shoot ratios will be calculated. Survival data will be analyzed by log-linear analysis of (truncated) survival times. Stem length, and the number of stems, axillary branches, follicles, and seed produced will be analyzed by a repeated measures analysis of variance. Biomass, the number of crown buds, and root-shoot ratios will be analyzed by analysis of variance.
Publications
- No publications reported this period
|
|