Magnolia trees rarely survive north of Philadelphia, but that isn’t the only reason this evergreen tree, which is more than 100 years old and stands 80 feet tall, is considered one of the Great Trees of New York City. Even the New York City Landmarks commission notes its importance having listed it as the only landmarked tree, and only living landmark, in all five boroughs. This Magnolia grandiflora, or laurel magnolia, was planted as a seedling in 1885 by William Lemken who had it sent up from North Carolina to…