Assessing a landscape as a continuum through history is critical in assessing cultural and historic value. Based on analysis, individual features may be attributed to a discrete period of introduction, their presence or absence substantiated to a given date and, therefore the landscape's significance and integrity evaluated. In addition, analysis allows the property to be viewed within the context of other cultural landscapes. In order for the landscape to be considered significant, character-defining features that convey its significance in history must not only be present, but they also must possess historic integrity. Location, setting, design, materials, workmanship, feeling and association should be considered in determining whether a landscape and its character-defining features possess historic integrity.
Preservation planning for cultural landscapes involves a broad array of dynamic variables.
Adopting comprehensive treatment and management plans, in concert with a preservation maintenance strategy, acknowledges a cultural landscape's ever-changing nature and the interrelationship of treatment, management and maintenance. The Standards are neither technical nor prescriptive, but are intended to promote responsible preservation practices that help protect our Nation's irreplaceable cultural resources. They cannot be used to make essential decisions about which contributing features of a cultural landscape should be retained and which can be changed . But once a specific treatment is selected, the Standards can provide the necessary philosophical framework for a consistent and holistic approach for a cultural landscape project. There are many practical and philosophical variables that influence the selection of a treatment for a landscape.