Potential Impacts and Control of the non-native Box Tree in Canada

Mariaelena A. Guarrasi

Frans Eggermont, 2018 perspectalis (Box Tree Moth)

Identified in Canada in August 2018 through iNaturalist

Karen Yukich, 2018 European Invasion

Status not recorded Native Invasive CABI, 2019 Host Plants

● Feeds on all common varieties of (Boxwood)

● Buxus is a native forest understory plant in Asia and

● Used as an ornamental worldwide

● In , C. perspectalis has been observed to feed on Euonymus alatus, E. japonicus, and Ilex purpurea, but this was not observed in Europe (Santi et al., 2015)

Mariaelena Guarrasi, 2019 Effects of BTM

Mariaelena Guarrasi, 2019 Predicted European Distribution ● Overwintering larvae survived temperatures of -25°C in (Nacambo et al., 2014)

● Northern Chinese and Eastern Russian populations experience overwintering temperatures of -30°C (Nacambo et al., 2014)

Nacambo et al., 2014 Mariaelena Guarrasi, 2019 Objectives

1. To determine the biology, phenology, and distribution of the species in Canada

2. To review possible control measures and their effectiveness

3. To examine what role citizen science will play in monitoring and control 1) BIOLOGY, PHENOLOGY, and DISTRIBUTION

Phenology: Life Cycle Florine Leuthardt, 2013 Leuthardt, Florine

Phenology: Life Cycle

Florine Leuthardt, 2013 Leuthardt, Florine Didier Descouens,Didier2014

Phenology: Life Cycle

Florine Leuthardt, 2013 Leuthardt, Florine

Didier Descouens,Didier2014 Didier Descouens,Didier2014

Phenology: Life Cycle

Florine Leuthardt, 2013 Leuthardt, Florine

Didier Descouens,Didier2014

Didier Descouens,Didier2014 2013 Leuthardt, Florine Biology and Phenology: Regional Differences

Europe Asia Canada

Generations 2a, 3b, c 3d ?

Number of Larval 3-7b, 7e 5-7f ? Instars

Minimum 8.38℃e 10.1℃d ? Temperature Threshold (Larval) rd nd th th th Overwintering Instar 3 c 2 -4 e, 4 or 5 f ?

a) Leuthardt et al., 2010 b) Leuthardt & Baur, 2013 e) Nacambo et al, 2014 c) Santi et al., 2015 f) Maruyama & Shinkaji, 1991 d) Maruyama & Shinkaji, 1987 Methodology

● Pheromone traps for capturing adult males - multiple trap designs were tested

● Boxwood in parks and gardens were monitored to record phenology and behavioural data

● Presence/absence data collected

● Measuring larval length as well as head width to determine instar

Mariaelena Guarrasi, 2019 Distribution: Results

● 1241 properties scouted for the presence of BTM

● 359 positive finds

● 384 possible positive finds (only damage)

Mariaelena Guarrasi, 2019 Biology and Phenology: Results

Europe Asia Canada

Generations 2a, 3b, c 3d 2

Number of Larval 3-7b, 7e 5-7f ? Instars

Minimum 8.38℃e 10.1℃d ? Temperature Threshold (Larval) rd nd th th th rd Overwintering Instar 3 c 2 -4 e, 4 or 5 f possibly 3

a) Leuthardt et al., 2010 b) Leuthardt & Baur, 2013 e) Nacambo et al, 2014 c) Santi et al., 2015 f) Maruyama & Shinkaji, 1991 d) Maruyama & Shinkaji, 1987 Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results Biology and Phenology: Results 2) CONTROL MEASURES Control Measures: Background ● Pheromone traps for adult males are commercially available (Kim & Park, 2013)

● Biopesticides based on Bacillus thuringiensis (Bt) are preferred over chemical insecticides (Kenis et al., 2013; CABI, 2019)

● Physical removal of larvae is possible but time consuming(CABI, 2019)

● Biological control is currently not effective (CABI, 2019) Mariaelena Guarrasi, 2019 Control Measures: Methodology

● Bt-based biopesticides were applied

● Pesticide has to be ingested by

caterpillars for effectiveness Mariaelena Mariaelena Guarrasi, 2019 ● Boxwood was monitored post- application Control Measures: Results

● Pheromone traps and physical removal were not effective for management

● Over 300 homes sprayed

● Biopesticides were effective at killing caterpillars

● Pesticide application should be repeated after each adult generation

Mariaelena Guarrasi, 2019 3) CITIZEN SCIENCE Citizen Science: Background

● Originally detected through a citizen science database

● Citizen science initiatives have shown promising outcomes (Gallo & Waitt, 2011) ○ Invaders of Texas Program ○ Invasive Plant Atlas of New England

● Errors in species identification can be diminished with the use of voucher specimens and validation of photographed sightings (Crall et al., 2011; Gallo & Waitt, 2011) Mariaelena Guarrasi, 2019 Citizen Science: Methodology

● Traps distributed to interested citizen scientists

● Weekly monitoring, monthly pheromone changes

● Positive finds validated with photographs

● Raised awareness through contact with over 1,000 homeowners Citizen Science: Results

● 70 traps distributed

● Identification skills were poor, photograph validation was essential

Mariaelena Guarrasi, 2019 iNaturalist research-grade observations Citizen Science: Results used Generations in Europe vs Canada

Santi et al., 2015

Mariaelena Guarrasi, 2019 Takeaways from my internship...

● BTM has established in Canada due to its cold tolerance and wide-spread host plant

● Effective control measures exist, but eradication is unlikely

● Citizen science can be a useful tool

● Collaboration between government, industry, public, and NGO’s is key

Mariaelena Guarrasi, 2019 Future Directions

● Collect more data on the phenology of BTM in Canada - larval head width

● Examine possible biological control measures

● Track the spread of BTM (more traps, more citizen science?)

Florine Leuthardt, 2013 Acknowledgements I would like to thank:

Dr. Sandy Smith for her supervision and assistance

Jennifer Llewellyn of OMAFRA, Erin Bullas-Appleton of CFIA, Jamie Aalbers of Landscape Ontario, and Bart Brussee of Sheridan Nurseries for their guidance and support of this project

Thank You for Listening! Literature Cited Billen, W. 2007. Diaphania perspectalis (: Pyrallidae) – a new moth in Europe. Mitteilungen der Entomologischen Gesellschaft Basel 57: 135-137. CABI. 2019. Cydalima perspectalis (box tree moth). Original text by Florine Leuthardt. In: Invasive Species Compendium. Wallingford, UK: CAB International. Retrieved from: https://www.cabi.org/ISC/datasheet/118433. Crall, A. W., Newman, G. J., Stohlgren, T. J., Holfelder, K. A., Graham, J., Waller, D. M. 2011. Assessing citizen science data quality: an invasive species case study. Conservation Letters 4:433-422. Gallo, T., Waitt, D. 2011. Creating a successful citizen science model to detect and report invasive species. BioScience 61(6):459-465. iNaturalist.org web application. Retrieved from: https://www.inaturalist.org/observations/15879362. Accessed 14 February 2019. Kenis, M., Nacambo, S., Leuthardt, F. L. G., Di Domenico, F., Haye, T. 2013. The box tree moth, Cydalima perspectalis, in Europe: horticultural pest or environmental disaster? Aliens: The Invasive Species Bulletin 33:38-41. Kim, J., Park, I. 2013. Female sex pheromone components of the box tree pyralid, Glyphodes perspectalis, in : field test and development of film-type lure. Journal of Asia-Pacific 16:473-477. Leuthardt, F. L. G., Baur, B. 2013. Oviposition preference and larval development of the invasive moth Cydalima perspectalis on five European box-tree varieties. Journal of Applied Entomology 137:437-444. Maruyama, T., Shinkaji, N. 1987. Studies on the life cycle of the box-tree pyralid, Glyphodes perspectalis (Walker) (Lepidoptera: Pyralidae). I. Seasonal adult emergence and developmental velocity. Japanese Journal of Applied Entomology and Zoology 31:226-232. [Japanese with English Abstract] Maruyama, T., Shinkaji, N. 1991. The life-cycle of the box-tree pyralid, Glyphodes perspectalis (Walker) (Lepidoptera: Pyralidae). II. Developmental characteristics of larvae. Japanese Journal of Applied Entomology and Zoology 35:221-230. [Japanese with English Abstract] Nacambo, S., Leuthard, F. L. G., Wan, H., Li, H., Haye, T., Baur, B., Weiss, R. M., Kenis, M. 2014. Development characteristics of the box-tree moth Cydalima perspectalis and its potential distribution in Europe. Journal of Applied Entomology 138:14-26. Santi, F., Radegheri, P., Sigurita, G. I., Maini, S. 2015. Sex pheromone traps for detection of the invasive box tree moth in . Bulletin of Insectology 68(1):158-160. van der Straten, M. J., Muus, T. S. T. 2010. The box tree pyralid, Glyphodes perspectalis (Lepidoptera: ), an invasive alien moth ruining box trees. Proceedings of the Entomological Society Meeting 21:107-111. van der Straten, M. J., Muus, T. S. T. 2010. The box tree pyralid, Glyphodes perspectalis (Lepidoptera: Crambidae), an invasive alien moth ruining box trees. Proceedings of the Netherlands Entomological Society Meeting 21:107-111. Wan, H., Haye, T., Kenis, M., Nacambo, S., Xu, H., Zhang, F., Li, H. 2014. Biology and natural enemies of Cydalima perspectalis in Asia: is there biological control potential in Europe? Journal of Applied Entomology 138:715-722.