In considering whether a structure is permanent in nature, a court should evaluate a variety of factors, such as the structure's size, weight, durability, stability and mobility. In this easement dispute, Bruce Zirinsky, holder of the servient estate, brought suit against his abutting neighbors, the dominant estate holders, Carnegie Hill Capital Asset Management, LLC and Michael and Janice Jamison, alleging that the defendants' erection of a play system within the easement area violated the easement's prohibition against permanent structures. The defendants' answer admitted the complaint's essential factual allegations but denied that the structure violated the easement and constituted a trespass. The defendants counterclaimed alleging that the plaintiff's planting of six spruce trees within the easement area constituted a trespass on their exclusive right to maintain landscaping within the easement area and interfered with their use of the easement. Following a court trial, the court concluded that the play set was a permanent structure and granted an injunction requiring its removal. The court ordered the plaintiff to remove three trees determining that they impeded access over the easement to a park and constituted an unreasonable use of the easement. The defendants appealed claiming, first, that all six trees violated the easement's terms. The Appellate Court agreed and reversed the judgment, in part. The easement granted the dominant estate holder the right to use the easement area "for any lawful purpose, including, but not limited to landscaping and maintaining the grounds…" It contained no restriction, save for the prohibition of permanent structures. The defendants introduced evidence that the trees interfered with the ability of the Jamison children to run around the area freely. Further, the plantings interfered with the defendants' right to landscape and maintain the area. However, the court's finding that the play system constituted a permanent structure was not clearly erroneous and upheld. Only after weighing such factors as a structure's size, weight, durability, stability and mobility, may a court render a factual finding as to whether the structure is a permanent one. The trial court credited the manufacturer's description of the play system as "built like a tank" and its "lifetime guarantee." The court observed the site and emphasized the significant size and weight of the "Monster Double Whammy" play system, which had not been moved since installation.