Monitoring the Effects of Emerald Ash Borer in the Philadelphia Urban Forest

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1 Monitoring the Effects of Emerald Ash Borer in the Philadelphia Urban Forest Natalie Howe Rutgers, The State University of New Jersey Center for Resilient Landscapes 2016 Fall Symposium 6/10/2016

2 Outline Emerald Ash Borer Insect life cycle EAB ecosystem effects Philadelphia urban forest Ash in Philadelphia EAB management plan EAB treatment Study: Goals of study Study design Preliminary results Long term plans

3 Emerald Ash Borer Agrilus planipennis Fairmaire Bark beetle Discovered in Michigan in 2002 & in Philadelphia in 2016 Kills north american Ash trees (Fraxinus sp.) as larvae drill through bark David Cappaert ;

4 Emerald Ash Borer and Ash Trees Ash trees are common in forests and urban areas. Dead trees can be hazardous, but removal is expensive. Solution: Ash tree treatment

5 Tree Cover in Philadelphia: 2.9 million trees, 7% of them are ash Hoehn et al., 2015

6 EAB discovered in Warrington PA, 15 miles north of Philadelphia, on March 14, 2012 Arrival in Philadelphia June(?) 2016 Plan for Conduct inventory treat 500 trees remove 5000 plant 2000 replacements

7 Ash treatment Emamectin benzoate chosen in Philadelphia because it has fewest effects on non target organisms, and applications protect trees for 2-3 years

8 Philadelphia Urban Forest Understory Deer herbivory provides competitive advantage to many invasive plants

9 Philadelphia Urban Forest Cobbs Creek Wissahickon / Fairmount Pennypack This study will help clarify some aspects of urban ash ecology: What are the consequences of ash loss for urban forest vegetation? What are the consequences of PPR treatment of ash trees for urban forest vegetation? How do urban forests respond differently to EAB than other forests?

10 Study design 4 study sites in each of 3 watershed parks (sites found using PPS maps of treatment locations) At each site, 4 plots are sampled Each plot includes 1 or more treated or untreated ash trees Sampled all levels of forest Canopy Understory Herbaceous layer Study will be repeated over course of ash tree decline Untreated Treated

11 Map of EAB monitoring Sites All Sites Include 1 PPR labeled ash Are 1 m off trail Include only unmanaged vegetation

12 12.62m radius plot: Live trees > 10cm dbh: Tree species Tree DBH Tree crown class Dataset: Canopy layer opy position Canopy rating Klooster et al., (2013) Q: How does canopy tree diversity and dominance change as ash trees die?

13 Woody debris 2 transects, 120 apart Fine woody debris Counts by size class S: < ¼ in M: ¼ in - 1 in L: 1in - 3 in Coarse woody debris (> 3in diam) Hardwood / Softwood Diameter at intersection Length Decay Condition Q: How does woody debris availability change as trees die? - What are implications for arthropods, birds, epiphytes? Peeling bark Heartwood sound Heartwood Klooster et al., rotten (2013); Powdery

14 8m radius plot Woody plants cm DBH Species DBH Woody plants < 2.5cm DBH but more than 1.37 m high Species Diameter at root collar subcanopy Q: What regeneration patterns change as trees die? Q: How does the subcanopy moderate the effects of canopy ash loss?

15 4 x 4m 2 diam plot % cover for each species Counts for woody seedlings: Seedlings cm established seedlings Seedlings <25cm tall young seedlings Herbaceous layer Q: How is understory affected by loss or treatment of ash trees?

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18 Data analysis Prepare a data paper for one of these (suggestions?) PLoS ONE Biomed Centeral BMC Ecology SpringerOpen - Botanical Studies Nature Publishing Group Scientific Data Pensoft NeoBiota Data to include Overstory tree and understory woody plant density, diversity and basal area. Understory diversity and comparison of native vs. non-native plants in the understory Woody plant germination in understory Woody debris prevalence Discussion points: How do the urban ash forests differ from rural forests where the ash death cycle has already taken place (Smith (2006) others. Does the ash-associated species diversity differ more between or within watersheds?

19 Questions for future years: How does death & treatment of ash trees affect the forests in terms of: Canopy composition? Forest structure Undestory diversity? Soil nutrient availability? Questions we can address with collaborations: Arthropod study: how does ash death and associated woody debris habitat influence arthropod communities? Epiphtye study: how does ash death influence epiphyte communities on live or dead trees? How do bird communities respond to ash death? Red bellied woodpecker: Ken Thomas, wikimedia Social questions: How are municipalities of NJ and PA addressing the ash crisis differently and what consequences will those decisions have? How do the people of Philadelphia respond to ash loss? Which Philadelphians care that it is happening? What is an effective, compelling, and non-depressing way to tell this story?

20 Questions? Emma Lasky Bryn Mawr College, USDA Forest Service Philadelphia Field Station Intern Sarah Dennis Every Kid in a Park Resource Assistant, USDA Forest Service, Philadelphia Field Station Grace Jesche University of Pennsylvania Master of Environmental Studies Program, USDA Forest Service Philadelphia Field Station. Volunteer Sarah Low USDA Forest Service Philadelphia Field Station Lara Roman USDA Forest Service Philadelphia Field Station Alain Plante University of Pennsylvania