Predicting High Quality Sites of Fraxinus nigra (black ash) Across Maine and Northern New York: An Approach to Prioritizing a Region’s Response to Environmental Stressors Kara K. Lorion 1, Dr. William H. Livingston 1, Dr. John Daigle 1, Dr. Robert J. Lilieholm 1, Dr. Darren J. Ranco 2 1 School of Forest Resources; University of Maine 2 Department of Anthropology; University of Maine Part of Maine’s Sustainability Solutions Initiative Study Objective: To develop a GIS map that indicates the probable location of sites in Maine and northern New York which are deemed high quality sites for F. nigra. This map can then be used by local land owners, basket-tree harvesters, tribes, foresters, and researchers to prioritize areas with F. nigra for protection against the impending emerald ash borer invasion and other environmental stressors. Current Situation Black ash is a culturally important species to Native American tribes in Maine & New York used in basket-making Black ash habitat is widespread across northeastern & northern midwest US, as well as southeastern & south central Canada Black ash habitat is widespread, but occurrence is rather rare in natural habitat Black ash most commonly found on wetland or poorly drained sites, however it thrives on upland, more mesic sites All ash species in North America are being threatened by the Emerald Ash Borer (EAB), first found in North America in 2002 (suspected arrival 1990s) EAB is an invasive insect from Asia that burrows into the bark of ash trees, destroys vascular tissue, and essentially girdles the tree (can take < 5 years) EAB is often attracted to stressed or weakened trees Resource managers need to prioritize the use of limited resources available in order to minimize the impact of EAB and other environmental stressors Methods Select sample sites in ME and in northern NY(2-3 natural communities per twp, 2 twps per ecoregion; 6 ecoregions in ME and 2 in NY) Pair natural communities in each twp; looking for 1 mesic or seasonally wet site, 1 flooded or poorly drained site; add 1 additional site if available Sample site = Four acre subplots ( acre total plot size) including a minimum of 12 black ash trees >12.7cm DBH Collect 2 cores/tree from 12 trees/site and measure soil characteristics, regeneration, tree growth, crown characteristics, and stand data according to FIA inventory protocol Collaborate with basket-tree harvesters to evaluate quality of sites & trees Measure cores using WinDendro & Velmex with J2X Use t-scores calculated from a 3-yr average of consecutive increments subtracted from the mean of the previous 3 yrs, and divided by the standard error, to quantify tree decline and identify trees with no/minimal decline Use T-score values <0 to indicate trees suffering growth decline Run logistic regressions to calculate probability of sites having good growing conditions for black ash EX: Volume of basket-quality wood = constant + depth-to-groundwater + natural community type Use variables derived from logistic regressions to determine layers for a GIS probability map depicting potential high quality sites in ME and NY Progress to Date Maine: 12 townships selected; 8 townships confirmed sites, 4 pending New York: 6 townships selected; all pending Approximately 150 cores collected from 75 trees in Maine Collaboration with harvesters in Maine established; have visited 2 sites Findings positive; more black ash & wider increment growth than expected Future without action: Would see loss of culture and income for Native American tribes Likely to see decline of a drought- tolerant riparian species Future of black ash may be plantations, with seed collection starting now to prepare Future with action: Determine where to allocate resources in high priority areas (via identification of high quality sites) Suppression of EAB populations and slowing infestation spread Preserve ecosystem functions; maintain black ash in natural habitats Above: Core from a high quality black ash tree Above: Core from a poor quality black ash tree Why Black Ash? Two part answer: socio-economic and ecological rationale Socio-economic: black ash is culturally important to traditions and history of Native American tribes, as well as economically important (est. $150,000/year from basketry in Maine alone) Ecological: black ash trees occupy a specific ecological niche, can survive and live in harsher conditions, and are one of the most drought-tolerant species of Fraxinus Acknowledgements Dr. Alan White Dr. Eleanor Groden Dr. Michael Day Maine Indian Basketmakers Alliance Dave StrubleNathan Siegert (funding research) Above: Bark likely to be seen on a high quality black ash tree Above: Bark likely to be seen on a poor quality black ash tree