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Detailed Investigations"I was delighted to find that Wells was a man of quite unusual breadth of interests and understanding. Our discussions were by no means limited to coast ecology; they included the ecology of bogs, savannas, grasslands, balds, the effects of fire and of primitive manthe origin of the Carolina Bays and human ecology." A. W. Bayer, Head of Department of Botany, University of Natal
While studying the sandhills, Wells came across a previously unknown type of pyxie moss. It was a rare, locally occurring form of the more common Pyxadanthera barbulata. After confirming his find with the New York Botanical Garden, Wells published his findings in the article, "A New Pyxie from North Carolina", which featured this image.
In the summers of 1933-34, Wells taught at New College located at the foot of Mount Pisgah. This location exposed Wells to the unsolved ecological question of the cause of grass balds, small treeless patches scattered throughout the mountains. After careful research and comparison to old Native American trails, he became convinced that they were caused by Native Americans who had disturbed the land when making camp. Building on the ecological term disclimax, meaning a plant community maintained by human disturbance, he coined the phrase archeological disclimax and used it to describe the balds.
Wells was the first ecologist to examine the early herbaceous stages of the succession of plants that occur on abandoned farm fields in North Carolina. He defined three communities which fit this description, the oldfield, meadow, and roadside communities. For each he noted a sequence of three stages that he found in the piedmont and eastern regions: annual pioneers, tall weeds, and broomsedge. This last stage was almost always followed by a pine dominated community.
In 1931, Wells presented this paper on the coastal plain. It features an in-depth discussion of the soils, vegetation, and other habitat features of the sandhills region, focusing on how the plants are able to survive and interact with the dry, hot climate. This publication is his first presentation of the theory he called the vicious circle, in which high temperatures and the sandy soil result in dry, easily combustible plants, leading to an increase in fires. The types of plants that survive the fires continue to promote high ground temperatures, thus repeating the cycle.
During World War II, Wells' ability to travel the state was hampered by gas rationing. However, by 1946, he was able to publish this study of Holly Shelter. As was the case for the Big Savannah, he identifies a high water table and the frequency of fire as major determinants in the ecology of the site. For the first time in his career, Wells made use of aerial photography in determining major vegetation features of the site. He compared the vegetation that he observed with the vegetation documented in the photographs some seven years earlier.
Carolina bays are wetlands in shallow depressions with an elliptical shape. With the proliferation of aerial photography in the 1930s, scientists became aware that they are all oriented in the same direction. Several scientists proposed that a meteor shower must have caused the bays, an idea Wells promoted. Although geologists have moved away from this theory, his other assertions, including the fact that the bays are growing, not filling in as others thought, and that they are newly developed lakes caused by water filling in depressions left by deep burning of peat from older bays, have been accepted. 
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