often leads to cracked sidewalks. References External links USDA Natural Resources Conservation Service: Quercus phellos Plant Profile Quercus phellos information and images from Vanderbilt University Interactive Distribution Map of Quercus phellos photo of herbarium specimen at Missouri Botanical Garden, collected in Missouri in 1897 phellos Trees of the United States Trees of the Southeastern United States Flora of the Southern United States Plants described in 1753 Taxa named by Carl Linnaeus