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Emerald ash borer (EAB)(Agrilus planipennis), an introduced wood-boring insect, has killed millions of ash (Fraxinus spp.) trees in the Midwest region of the United States and Canada. However, in some areas where EAB has caused almost complete mortality of mature ash trees, a small number of healthy ash trees intermingled with the dead ash trees have been discovered, sparking interest in these “lingering” ash trees. Here we present the results of surveys in 2010 and 2011 of two populations of surviving ash trees in southeast Michigan and northwest Ohio, where the vast majority of ash trees had died by 2008. A 2010 survey of ash trees≥ 10 cm DBH (diameter at breast height, 1.4 m) along 10 km of floodplain forest in northwest Ohio found 2.6 percent of the ash trees were alive and 1 percent of the ash trees were healthy in an area where most of the ash trees had died by 2008. The canopy condition and EAB symptoms of these surviving trees were recorded. A repeated survey in 2011 found that most of the surviving trees that had healthy canopies in 2010 remained healthy in 2011, while trees with unhealthy canopies declined or died by 2011. In southeast Michigan, a population of living ash trees was discovered in 2010, at which time 39 trees were tagged and their canopy condition and EAB symptoms were recorded. When the trees were re-surveyed in 2011, the same pattern observed in northwest Ohio was evident: most of the trees that had healthy canopies in 2010 remained healthy in 2011, while trees with unhealthy canopies declined or had died by 2011. At both sites, some of the trees with healthy canopies show evidence of past …