Source: CONNECTICUT AGRICULTURAL EXPERIMENT STATION submitted to
MITIGATING LYME DISEASE RISK THROUGH CONTROL OF AN INVASIVE PLANT SPECIES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0224920
Grant No.
(N/A)
Project No.
CONH00577
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Mar 1, 2011
Project End Date
Feb 28, 2014
Grant Year
(N/A)
Project Director
Williams, S.
Recipient Organization
CONNECTICUT AGRICULTURAL EXPERIMENT STATION
PO BOX 1106
NEW HAVEN,CT 06504
Performing Department
Forestry & Horticulture
Non Technical Summary
Issue: Japanese barberry, a plant species native to Japan, was brought to the United States in the late 1800s. It has since escaped cultivation and has invaded and become naturalized in at least thirty one states and is listed as invasive in twenty. Research has shown that Japanese barberry can alter soil structure and function and severely limits native forest plant regeneration. Japanese barberry has also been shown to create microclimatic conditions that are favorable for blacklegged tick survival. Ticks found in Japanese barberry infestations have been shown to have elevated infection prevalence with the Lyme disease-causing spirochete Borrelia burgdorferi. The impacts of Japanese barberry management on blacklegged ticks, white-footed mice, and associated Borrelia burgdorferi presence needs to be documented in the interest of public health. Response: Researchers in the Department of Forestry and Horticulture at The Connecticut Agricultural Experiment Station have established five research plots and are working on a sixth to examine the effect of Japanese barberry management on blacklegged ticks, white-footed mice, and Borrelia burgdorferi prevalence. The Aquarion Water Company, South Central Connecticut Regional Water Authority, Division of Forestry of the Connecticut Department of Environmental Protection, The Nature Conservancy, the University of Connecticut, and Lord Creek Farm have all provided use of their land and personnel to assist with this study. Impact: Japanese barberry is an exotic invasive plant that overwhelms the forest shrub layer and virtually eliminates other native plants. In addition, it harbors increased abundances of blacklegged ticks infected with disease-causing organisms that can be transmitted to humans. Managing barberry infestations can improve the health of forests and citizens of the State of Connecticut.
Animal Health Component
20%
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
7233120117020%
7223120117015%
7213120117015%
1350850107010%
1360850107010%
3123120113010%
1230850107010%
2052420107010%
Goals / Objectives
Our previous work revealed that Japanese barberry provides a microclimate favorable for blacklegged tick survival. Because barberry patches retain high relative humidity levels throughout the day, blacklegged ticks found within are much less prone to desiccation-induced mortality and can spend more time seeking hosts and less time retreating to high humidity refugia. We observed white-tailed deer using barberry patches for cover and bedding areas. Deer also can transport ticks within and between barberry patches. We still do not fully understand why there are more ticks infected with B. burgdorferi in barberry infestations than in adjacent forests without barberry. Although not shown by our data, we suspect that barberry provides white-footed mice protection from predators and that mouse populations should be higher in areas with barberry than in areas without barberry. Our data may not show this relationship due to edge effects arising from the small size of our original study areas (0.5 and 2.0 ha). Because home ranges of white-footed mice can be upwards of 0.15 ha (DeGraff and Rudis 1986), much of the original study areas are in fact habitat edges with mice moving between areas with and without barberry. Therefore, estimations of mouse populations could have been confounded by immigration of mice into areas without barberry via emigration of mice out of barberry infestations. Presently we are working to clear much larger areas of Japanese barberry (2 blocks of approx. 6.5 ha each) in Lyme, CT. We feel that a larger block of cleared barberry will limit edge effects and provide a better understanding of the impact of barberry control on mouse populations. We plan to trap mice in these areas as well as continue to sample ticks and trap mice in the established research areas. Comparing results from the original study areas with the larger cleared block in Lyme will allow a comparison of the impact of Japanese barberry removal at several spatial scales to continue tracking small mammal and blacklegged tick abundance population dynamics. Objectives: 1.Determine impact of Japanese barberry removal at several spatial scales on blacklegged tick abundance and associated Borrelia burgdorferi prevalence. 2.Determine impact of Japanese barberry removal at several spatial scales on the white-footed mouse population and associated Borrelia burgdorferi prevalence. Expected outputs would include a better understanding of the deleterious impacts of non-native plant species on native ecosystems and would also provide a scientific justification for management of this particular plant.
Project Methods
Tick Sampling: Adult blacklegged ticks will be sampled in all habitats at all study areas using standard flagging techniques when ticks are active in early spring and late autumn. A 1 m2 piece of white duck cloth attached to a dowel will be used to flag vegetation or the forest floor over linear transects totaling 200 m in each habitat plot at North Branford A, Redding A, and Storrs. Linear transects totaling 400 m will continue to be flagged in all habitat plots at both Redding B and North Branford B. Linear transects totaling 400 m will be established and flagged at the new Lyme location. Flags will be checked for ticks approximately every 15-20 m. Gathered ticks will be transported to a laboratory, stored in a hydrator, and incubated at 10 degrees C. Blacklegged tick densities (ticks/ha) will be calculated for each plot, within each study area, for each year of the study. To determine B. burgdorferi presence, gathered tick midguts will be dissected under a stereo microscope and contents smeared on 12 well glass microscope slides (# 30-103HTC, Thermo Fisher Scientific, Portsmouth, NH). Borrelia burgdorferi spirochetes will be identified in midgut contents by using indirect fluorescent antibody (IFA) staining methods with monoclonal antibody H5332, which is specific for outer surface protein A of B. burgdorferi (Magnarelli et al. 1994). Fluorescein isothiocyanate-conjugated goat anti-mouse immunoglobulins (KPL, Inc., Gaithersburg, MD) will be diluted 1:40 in phosphate-buffered saline solution and used as the second antibody. Procedural details will continue to follow established protocols (Anderson et al. 1991, Magnarelli et al. 1994, Magnarelli et al. 1997). All data will be compiled and used for publication in relevant peer-reviewed scientific journals. Mouse Trapping: Mice will be trapped using folding Sherman live traps at the original study areas (North Branford B, North Branford A, Redding A, Redding B, Storrs) as well as the new study area (Lyme) from June-September. Twenty traps will be set in permanent grids at 15m spacing at each of the three treatment plots (n = 60) at each replicate study area and baited with peanut butter. Captured mice will be temporarily sedated using the inhalant anesthetic isofluorane. Each mouse will receive a uniquely numbered ear tag. A 0.1 cc blood sample will be drawn via cardiac puncture with an insulin syringe with a 1.6 cm, 27 gauge needle. Blood samples will centrifuged, the serum will be separated from whole blood, and all will be stored at -50 degrees C until B. burgdorferi antibody titer levels can be determined using procedures as described in Magnarelli et al. (2006). Additionally, the number of larval ticks feeding on mice will be recorded without removal after each capture. Sedated mice will be allowed to recover from the effects of isofluorane and will be released back to the plot from which they were originally captured.

Progress 03/01/11 to 02/28/14

Outputs
Target Audience: Local Land Trusts and other conservation organizations, private landowners, land managers, forest products industry personnel, hikers, bikers, outdoor enthusiasts, municipalities, garden clubs, local Audubon Society chapters, undergraduate and graduate students, elementary school students, and urban foresters. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The project provided an excellent opportunity for a graduate student to earn an advanced degree while also helping to protect the health of the citizens of the State of Connecticut and beyond. Additionally, it has created an excellent educational platform to demonstrate to undergraduate students the relationship between invasive plants, ticks, and mice and also to explain and better understand the Lyme disease ecological cycle. Additionally, it has created an excellent opportunity to put a focus on the management of invasive plants as in this case, they can have an indirect negative effect on public health. As such, it has been a very popular subject for lectures to various Land Trusts, garden clubs, and other agencies that manage land. It has energized their base and we have been seeing an increased interest in people getting outside and using our techniques to manage invasives in the interest of both the health of the public and ecosystems alike. How have the results been disseminated to communities of interest? Results have been disseminated to the public in the form of workshops, bulletins, popular articles, as well as peer-reviewed publications. Additionally, public lectures are frequently given on the topic as requested. It is a very popular ecological talk and is of interest and well received by the public. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? We were successful in clearing the two larger areas of invasives in Lyme, CT and have been capturing mice there for three years toward our research hypothesis that Japanese barberry provides an ideal habitat for white-footed mice resulting in increased blacklegged tick abundances and associated tick-borne disease risk. We continue to sample blacklegged ticks from the site as well as our 5 other historic research sites. Our graduate student, Ms. Floyd, successfully defended her Master's Degree at the University of Connecticut using these data toward her thesis. She used the program MARK to conduct Jolly-Seber mark-recapture analyses on white-footed mouse abundance in areas of Japanese barberry domination and in areas where barberry was managed to areas where barberry was minimal or absent. She found that there were no significant differences in mouse population abundances between the various treatment areas, though significant differences in overall mouse abundances fluctuated by year and by research site. She also determined that the driving health risk to the public was the increased pathogen vector (ticks) and their positive association with Japanese barberry dominated sites. We had hypothesized that it was differing reservoir (mouse) abundances that was driving the increased tick-borne pathogen risk in this system. But as it turns out, this was not the case and it was determined that the increased tick abundances in the Japanese barberry dominated areas infecting and reinfecting the same reservoir cohort was ramping up the infection prevalence in the mice, which then lead to significant increases in abundances of Borrelia-infected ticks in Japanese barberry dominated areas. Both areas where Japanese barberry had been managed and was minimal or absent had significantly lower densities of infected ticks. Ms. Floyd will continue to investigate this system toward her Ph. D. also at the University of Connecticut.

Publications

  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2014 Citation: Invited lecture on "Barberry, deer, and ticks" to the Southbury, CT Land Trust, 27 May 2014 (Ward)
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2014 Citation: Invited lecture on "Barberry, deer, and ticks" to the West Haven, CT Land Trust, 27 May 2014 (Ward)
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2013 Citation: Invited lecture titled Ecological interconnectedness between a native ectoparasite, an alien invasive shrub, a native rodent, and a native invasive mammal and potential health impacts to humans to the Potapaug Chapter of the National Audubon Society Lecture Series, Old Lyme, CT, 7 November 2013.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2014 Citation: Invited lecture at the headquarters of the Stewart B. McKinney National Wildlife Refuge titled TICKED OFF!: Invasive Plants and Lyme Disease  A Surprising Connection in Westbrook, CT 27 March 2014.


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: The target audience for this project includes local land trusts and other conservation organizations, private landowners, land managers, forest products industry personnel, hikers, bikers, outdoor enthusiasts, municipalities, garden clubs, local Audubon Society chapters, undergraduate and graduate students, elementary school students, and urban foresters. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The project has provided an excellent opportunity for a graduate student to use data gathered from the project to help her to earn two advanced degrees while also helping to protect the health of the citizens of the State of Connecticut and beyond. Additionally, I have been contacted just recently by another graduate student who is interested in the small mammal data, investigating whether tick-borne pathogens are less prevalent in areas where small mammal populations are more diverse. How have the results been disseminated to communities of interest? Results have been disseminated to the public in the form of workshops, bulletins, popular articles, as well as peer-reviewed publications. Additionally, public lectures are frequently given on the topic as requested. It is a very popular ecological talk and is of interest and well received by the public. What do you plan to do during the next reporting period to accomplish the goals? We will continue to trap mice in our research areas during the summer months.We will continue to sample for blacklegged ticks in our sites as well in the spring, summer, and fall. We will continue to monitor tick-borne pathogen presence in sampled ticks, as well as in the blood samples gatheredfrom captured mice. We will continue to work with graduate students on mouse population assessments in our research locations. We will continue to give public talks and disseminate information as requested.

Impacts
What was accomplished under these goals? We were successful in clearing the two larger areas of invasives in Lyme, CT and have been capturing mice there for two years toward our research hypothesis that Japanese barberry provides an ideal habitat for white-footed mice, resulting in increased blacklegged tick abundances and associated tick-borne disease risk. We continue to sample blacklegged ticks from the site as well as our 5 other historic research sites. Our graduate student, Ms. Floyd, is currently investigating the differing mouse population abundances at our different research sites and treatments. She is using program MARK to conduct Jolly-Seber mark-recapture analyses. During this reporting period, we trapped mice at each of our 6 research sites on three occasions resulting in 90 captures of 67 unique mice. Blood samples were drawn from all mice. Mice trapped from unmanipulated barberry stands had an average of 7.7 larval ticks, mice trapped from areas where barberry was managed had 2.9 larval ticks/mouse, and mice from areas where barberry was minimal or absent had 3.1 larval ticks/mouse. Additionally, each of the 6 sites were sampled for adult ticks on 4 separate occasions. In unmanipulated barberry stands, there wasan average of205 ticks/acre; where barberry was managed had54 ticks/acre, andareas where barberry was minimal or absent had23 adult ticks/acre. Results continue to show that Japanese barberry infestations are a favorable microclimate for blacklegged ticks.

Publications

  • Type: Conference Papers and Presentations Status: Other Year Published: 2013 Citation: Invited lecture given titled Invasive Plant Species, Blacklegged Ticks, and Lyme Disease, Town of Greenwich Symposium on Lyme Disease, Greenwich, CT, 21 February 2013.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2013 Citation: Invited lecture given titled Japanese Barberry Control Treatments and Herbivory Reduction on Non-Native and Native Plant Communities, 7th Connecticut Conference on Natural Resources, Storrs, CT, 18 March 2013.
  • Type: Other Status: Accepted Year Published: 2013 Citation: Ward, J. S., S. C. Williams, and T. E. Worthley. 2013. Japanese barberry control methods reference guide for foresters and professional woodland managers. Connecticut Agricultural Experiment Station Special Bulletin - February 2013. 12p. http://www.ct.gov/caes/lib/caes/documents/publications/special_bulletins/special_bulletin_feb_2013_ward.pdf


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: In many Connecticut forests with an overabundance of white-tailed deer (Odocoileus virginianus), Japanese barberry (Berberis thunbergii) has become the dominant understory shrub. This exotic invasive shrub provides habitat favorable to blacklegged tick (Ixodes scapularis) and white-footed mouse (Peromyscus leucopus) survival. To determine mouse and larval tick abundances at six replicate sites, we have been trapping mice since 2007 in unmanipulated dense barberry infestations, areas where barberry was controlled, and areas where barberry was minimal or absent. The number of feeding larval ticks/mouse was recorded. Adult and nymphal ticks were sampled along permanent draglines within each treatment area, retained, and were tested for the presence of Borrelia burgdorferi, the causal agent of Lyme disease in humans, pets, and domesticated livestock. To date, there have been 2,007 white-footed mice captures. The number of captured mice did not differ between treatments. However, the average number of feeding larval ticks per mouse was highest on mice captured in dense barberry (6.1 larvae/mouse). We have collected 5,497 blacklegged ticks and adult tick densities in dense barberry (239/acre) were higher than in both controlled barberry (136/acre) and no barberry (75/acre) areas. Ticks sampled from dense barberry infestations and controlled barberry areas had similar infection prevalence with B. burgdorferi, 52 and 53% respectively. Adult tick infection prevalence with B. burgdorferi varied widely between treatments and study areas, but was lowest in areas where barberry was absent and generally lower where barberry was controlled. This in concert with the overall reduction in the adult tick cohort in areas where barberry was controlled resulted in 124 B. burgdorferi-infected ticks/acre in dense barberry, 40/acre where barberry was controlled, and 11/acre where barberry was absent. Results indicate that managing Japanese barberry will have a positive effect on public health by reducing the number of B. burgdorferi-infected blacklegged ticks that can develop into motile life stages that commonly feed on humans. Mouse trapping and tick sampling efforts will continue for several more years to monitor long-term effects of controlling Japanese barberry. Data from this work have been published in two peer-reviewed scientific journal articles and have been referenced in 12 others. In collaboration with the University of Connecticut, Department of Extension, results have been presented in over 200 different lectures ranging from university symposia to garden club talks and land trust workshops to professional conferences. Informational packets summarizing this research were distributed at the majority of these lectures. PARTICIPANTS: Individuals: Michael Short, Research Technician, Connecticut Agricultural Experiment Station Megan Floyd, Seasonal Employee, Connecticut Agricultural Experiment Station Partner Organizations: Aquarion Water Company The Nature Conservancy Connecticut Department of Energy and Environmental Protection Lord Creek Farm South Central Connecticut Regional Water Authority University of Connecticut, Storrs TARGET AUDIENCES: Target Audiences: Local Land Trusts and other conservation organizations, private landowners, hikers, bikers, outdoor enthusiasts, municipalities. Underserved audiences: Latinos working in landscaping or agricultural settings who would be exposed to Japanese barberry and resulting tick bites and associated Lyme disease threat. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
This research is not only of interest from an ecological perspective, but also serves to scientifically document the potential negative impacts an invasive plant can have on human health. This research has been featured on the radio, gardening and scientific websites, and multiple forest land managers have used it to strengthen their argument for the increased need to control invasive plants. Results from this research will lead to improved interest in the control of invasives, and ultimately, a reduction in the number of ticks capable of causing Lyme disease in humans and domesticated animals. Various entities within the towns of Redding, Weston, Easton, Guilford, Greenwich, Hampton, Mansfield, Newtown, Ridgefield, Lyme, Norfolk, Litchfield, North Branford, and Coventry and in the states of Massachusetts, Rhode Island, Vermont, and New York have used these results in part to justify equipment purchase and initiate or reinvigorate invasive plant control programs. Many different University Departments of Extension (Connecticut, New York, Maryland, Vermont, Pennsylvania) are teaching these research findings in their Master Gardener certification programs. Additionally, numerous towns in Connecticut as well as the states of Delaware and Maryland and the Province of British Columbia have used our research linking deer and invasive plants to scientifically justify their respective deer management programs.

Publications

  • Bobowick, K. 2012. Town invests in cutting back the invasives at Fairfield Hills. The Newtown (CT) Bee. http://newtownbee.com/News/2012-08-30__14-13-32/Town+Invests+In+Cutti ng+Back+The+Invasives+At+Fairfield+Hills.
  • Fahrner, A. J. 2012. Beware the impact of invasive plants. Poughkeepsie Journal. http://www.caryinstitute.org/newsroom/beware-impact-invasive-plants.
  • Foran, S. 2012. Controlling Japanese Barberry Helps Stop Spread of Tick-Borne Diseases. UConn Today. http://today.uconn.edu/blog/2012/02/controlling-japanese-barberry-hel ps-stop-spread-of-tick-borne-diseases/
  • Gaudet-Wilson, M. and A. Henderson. 2012. The Barberry-Tick Connection: Barberry Blitz in Newtown, CT, Spring 2012. http://www.hamlethub.com/newtown-life/cat/health/6872-the-barberry-ti ck-connection.
  • Green, M. 2012. Conservation Commission sets sights on invasive plants. Town of Harvard (MA) Conservation Commission. http://www.harvardpress.com/Home/AllArticles/tabid/2190/ID/9335/ConsC om_sets_sights_on_invasive_plants.aspx.
  • Greene, E. 2012. The aliens are invading our hardwood forests. Upper Hudson River Region News Enterprise. http://www.newsenterprise.org/news/2012/may/16/aliens-are-invading-ou r-hardwood-forests/.
  • Henderson, A. 2012. Be wary of barberry plants. Wethersfield's (CT) HamletHub. http://www.hamlethub.com/wethersfield-life/cat/home-and-garden/11411- be-wary-of-barberry-plants.
  • Hendry, J. 2012. Now is the time to identify and control Japanese barberry. Joene's Garden. http://www.joenesgarden.com/2012/03/30/now-is-the-time-to-identify-an d-control-japanese-barberry/.
  • Landro, L. 2012. This Season's Ticking Time Bomb. Wall Street Journal. http://online.wsj.com/article/SB1000142405270230340470457730563026798 8716.html.
  • Mustane, F. 2012. Town Takes Aim at Invasive Japanese Barberry. Newtown, CT Patch. http://newtown.patch.com/articles/town-takes-aim-at-invasive-japanese -barberry-shrubs.
  • Ross, J. 2012. Beware of barberry, a 'scaffold for ticks'. The Home Monthly. http://thehomemonthly.com/2012/08/2351-beware-of-barberry-a-scaffold- for-ticks/.
  • Rowlands, W. 2012. So what's all this I hear about invading plants Fairfield County (CT) Sun. http://www.fairfield-sun.com/2654/so-whats-all-this-i-hear-about-inva ding-plants/.
  • Smith, H. 2012. Japanese barberry: a ticking time bomb. Adirondack Daily Enterprise. http://www.adirondackdailyenterprise.com/page/content.detail/id/53293 5.html.
  • The Faith Middleton Show. 2012. Lyme Disease in 2012. Connecticut Public Radio. http://www.yourpublicmedia.org/content/wnpr/faith-middleton-show-lyme -disease-2012-plus-authors-father-s-love-and-roxy-s-forever-ho
  • Williams, S. C. 2012. Impact of a warm winter on deer tick abundance. Connecticut Timber Producers Newsletter.
  • Electronic articles where this research was highlighted in 2012.
  • Anon. 2012. Invasive Species, Best Control Practices- Japanese Barberry (Berberis thunbergii). Michigan Department of Natural Resources, Michigan Natural Features Inventory, 2/2012. mnfi.anr.msu.edu/invasive-species/JapaneseBarberryBCP.pdf.
  • Anon. 2012. Town of Ridgefield, CT Conservation Commission. Japanese Barberry (Berberis thunbergii). http://www.ridgefieldct.org/content/52/124/15162.aspx.
  • Barnard, P. 2012. Ridgefield Urges Residents to Remove Japanese Barberry. Ridgefield Patch. http://ridgefield.patch.com/articles/ridgefield-urges-residents-to-re move-japanese-barberry#comment_5799943.


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: In many Connecticut forests with an overabundance of white-tailed deer (Odocoileus virginianus), Japanese barberry (Berberis thunbergii) has become the dominant understory shrub. This exotic invasive shrub provides habitat favorable to the blacklegged tick (Ixodes scapularis) and white-footed mouse (Peromyscus leucopus) survival. To determine mouse and larval tick abundances at six replicate sites, we have been trapping mice since 2007 in unmanipulated dense barberry infestations, areas where barberry was controlled, and areas where barberry was minimal or absent. The number of feeding larval ticks/mouse was recorded. Adult and nymphal ticks were sampled along permanent draglines within each treatment area, retained, and were tested for the presence of Borrelia burgdorferi, the causal agent of Lyme disease in humans, pets, and domesticated livestock. To date, there have been 1,697 white-footed mice captures. The number of captured mice did not differ between treatments. However, the average number of feeding larval ticks per mouse was highest on mice captured in dense barberry (6.1 larvae/mouse). We have collected 4,568 blacklegged ticks and adult tick densities in dense barberry (259/acre) were higher than in both controlled barberry (154/acre) and no barberry (82/acre) areas. Ticks sampled from dense barberry infestations and controlled barberry areas had similar infection prevalence with B. burgdorferi, 52 and 53% respectively. Adult tick infection prevalence with B. burgdorferi varied widely between treatments and study areas, but was lowest in areas where barberry was absent and generally lower where barberry was controlled. This in concert with the overall reduction in the adult tick cohort in areas where barberry was controlled resulted in 113 B. burgdorferi-infected ticks/acre in dense barberry, 49/acre where barberry was controlled, and 12/acre where barberry was absent. Results indicate that managing Japanese barberry will have a positive effect on public health by reducing the number of B. burgdorferi infected blacklegged ticks that can develop into motile life stages that commonly feed on humans. Mouse trapping and tick sampling efforts will continue for several more years to monitor long-term effects of controlling Japanese barberry. Previously gathered data from this work have been published in two peer-reviewed scientific journal articles and have been referenced in 11 others. In collaboration with the University of Connecticut, Department of Extension, results have been presented in over 184 different lectures ranging from university symposia to garden club talks and land trust workshops to professional conferences (many of which occurred during this report period). Informational packets summarizing this research were distributed at the majority of these lectures. PARTICIPANTS: Individuals: Scott C. Williams-PI; Jeffrey Ward-Invasive control, extension; Joseph Barsky-Invasive control, tick collection, mouse trapping, extension; Michael Short-Invasive control, tick collection, mouse trapping, extension; Maribeth Chassey-Invasive control, tick collection, mouse trapping; Edward Candrella-Invasive control, tick collection, mouse trapping; Elizabeth White-Invasive control, tick collection, mouse trapping; Carolyn Ariori-Invasive control, tick collection, mouse trapping---Partners: University of Connecticut Department of Extension, South Central Connecticut Regional Water Authority, Aquarion Water Company, Connecticut Department of Energy and Environmental Protection, Forestry Division, The Nature Conservancy, Joshua's Trust, Guilford Land Conservation Trust, Town of Mansfield, Town of Greenwich, Town of Guilford, Great Mountain Forest Corp., White Memorial Foundation, Providence Water Company, Norcross Wildlife Foundation--- Training or professional development: -Workshop of Japanese barberry control in Hampton in cooperation with Joshua's Tract Conservation & Historic Trust (30 participants) (12/21/2010); -Flame-Weeding for Invasive Shrub Control Workshop sponsored by the USDA-NRCS in Vernon (42 participants) (3/22/2011); -Workshop of Japanese barberry control in Norfolk in cooperation with Great Mountain Forest (21 participants) (10/29/2011); -Workshop of Japanese barberry control in Litchfield in cooperation with White Memorial Foundation (26 participants) (11/15/2011); -Workshop of Japanese barberry control in Guilford in cooperation with Guilford Land Conservation Trust (13 participants) (12/4/2011); -Workshop of Japanese barberry control in Mansfield (20 participants) (12/30/2011) TARGET AUDIENCES: Target audiences were large landowners with invasive species problems: specifically land trusts, water companies, municipalities, corporations, and large private landowners. Workshops and demonstrations were well advertised and open to all members of the public to attend. This research was specifically presented to incarcerated youth on two occasions at the Manson Youth Facility in Cheshire, CT. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
This research is not only of interest from an ecological perspective, but also serves to scientifically document the potential negative impacts an invasive plant can have on human health. This research has been featured on the radio, gardening and scientific websites, and multiple forest land managers have used it to strengthen their argument for the increased need to control invasive plants. Results from this research will lead to improved interest in the control of invasives, and ultimately, a reduction in the number of ticks capable of causing Lyme disease in humans and domesticated animals. Various entities within the towns of Redding, Weston, Easton, Guilford, Greenwich, Hampton, Mansfield, Lyme, Norfolk, Litchfield, North Branford, and Coventry and in the states of Massachusetts, Rhode Island, and New York have used these results in part to justify equipment purchase and initiate or reinvigorate invasive plant control programs. Additionally, numerous towns in Connecticut as well as the states of Delaware and Maryland and the Province of British Columbia have used our research linking deer and invasive plants to scientifically justify their respective deer management programs.

Publications

  • Williams, S. C. and J. S. Ward. 2011. Relationship between Japanese barberry and blacklegged ticks. Guilford Land Conservation Trust Newsletter.
  • Williams, S. C., J. S. Ward, and T. E. Worthley. 2011. It is not the heat, it is the humidity: Deer ticks thrive in Japanese barberry. Connecticut Home and Garden Education Center Newsletter.