Abstract Detail

Ecology

Kilgore, Jason Scott [1], Dolan, Benjamin James [2].

Driving changes: Exploring the influence of emerald ash borer (Agrilus planipennis) on the diversity of forest ground flora.

Agrilus planipennis (EAB) is an exotic, invasive insect, discovered in North America in 2002. The insect is native to temperate forests of eastern Asia, where its larvae feed on the phloem and inner bark of ash (Fraxinus spp.) without much noticeable impact. In EAB’s introduced range, the impact is much more lethal: infested ash trees die within 3-5 years. As of 2015, the insect has spread to 25 U.S. states and two Canadian provinces, and many ash trees in southern Michigan and northern Ohio have succumbed and fallen. Prior research shows that the decline of each tree provides resources that allow for increased growth of established canopy trees; but the impact of the shifting resources on ground flora is not fully known. We utilize long-term research plots developed as part the Ecological Research as Education Network’s Permanent Forest Plot Project as a basis on which to build additional protocols that examine the loss of overstory ash trees on the diversity of ground flora and dominance of woody seedlings and saplings. Our research includes sites in four locations in eastern North America where ash trees are present and have succumbed, are currently infested, or are not yet affected by EAB.
Preliminary results indicate that changes in diversity of ground flora from 2012 to 2015, as measured by the inverse Simpson Index, are minimal. In northwest Ohio sites, where most ash trees died by 2012, initial analysis indicates a negligible increase in diversity, from 0.90 to 0.93. This did not differ substantially from observations in southwest Pennsylvania, where diversity increased from 0.88 to 0.93, over the same period. Ash trees in southwest Pennsylvania were impacted by EAB but had not shown decline in canopy cover during the study period. Among the woody species, trends in species dominance varied by location. Fraxinus and Celtis occidentalis increased in the sapling layer in Ohio sites, while invasive species such as Celastrus orbiculatus, Euonymus, and Lonicera increased in Pennsylvania sites. In the seedling layer, both sites saw a decrease in Ulmus, while Acer saccharum and Carya cordiformis increased in Ohio and Crataegus and Prunus serotina increased in Pennsylvania. As EAB continues to spread through forests of eastern North America and data from additional sites are contributed to this collaborative project, we expect to further elucidate the role of other factors, including prior vegetation composition, soil differences, and geographic location.

Related Links:
EAB Impacts Study (EREN - PFPP)

1 - Washington & Jefferson College, Biology, 60 South Lincoln Street, Washington, PA, 15301, USA
2 - The University of Findlay, Natural Sciences, 1000 N Main Street, Findlay, OH, 45840, USA

Keywords:
ash
EAB
diversity
EREN.

Presentation Type: Oral Paper
Session: 15, Ecology Section: Forest Ecology
Location: 104/Savannah International Trade and Convention Center
Date: Tuesday, August 2nd, 2016
Time: 9:15 AM
Number: 15006
Abstract ID:577
Candidate for Awards:None