One of America's most visionary prairie school landscape architects, Jensen's design work incorporated horizontal lines in landforms and stonework, the natural branching habits of plants, and the restoration and conservation of native plant materials. The collection is comprised mainly of landscape architectural drawings for more than four hundred and sixty projects, along with a small amount of manuscript material and photographs.
Jensen's landscape work encompassed a broad range of projects -- residential, subdivisions, parks and preserves, schools and educational facilities, hospitals, office complexes and government centers, all of which are represented in the collection. Jensen's view of landscape architecture as a social force for integrating art, home, and commerce is a significant and unique characteristic of his work. While the native landscape itself, both as he experienced it in Denmark and in America, was his primary inspiration, Jensen was also influenced by the social and economic reform movements of the late nineteenth and early twentieth centuries. His theories related to urban planning, his recognition of the restorative value of nature and wilderness, his genuine concern for the environment, and his love of people are reflected in the material and will interest researchers from a range of disciplines and subject areas -- although the documentation is almost wholly visual.
When looked upon as a whole, the collection richly illustrates Jensen's consistent philosophy of design. While each project had its own character reflecting the nature of the site and client requirements, certain recurring design features in the drawings are evidence of Jensen's particular style. His plans almost always show plants in masses -- creating unity through repetition of similar species, textures, and forms and suggesting groupings found in native habitats. The hawthorn, with its low, horizontal branching habit, a symbol of the prairie for Jensen, is found often in his designs, along with other small native trees, sometimes scattered individually, but more often in repetition to reinforce prairie views and provide a transition to larger trees along woodland borders. Also evident is the adept handling of open spaces found at the core of most of his designs -- great meadows, linear "long views," prairie views and prairie vistas, sun openings, garden rooms, clearings. Smaller clearings and sun openings emphasize the importance Jensen placed on light and shadow as integral to the art of landscaping; a series of broad curving drives, footpaths, and trails invite movement and ensure that visitors experience sequences of sun and shade, sometimes leading "to the setting sun" or "to the rising sun." Water is another distinctive feature -- quiet pools, prairie rivers, lagoons, ponds, streams enhanced with rock work skillfully executed to suggest ravines and bluffs. The drawings also provide many examples of Jensen's council rings tucked into edges of woodland borders, surrounded by trees or placed to view a meadow or lake; player's greens created for outdoor drama; and small areas set aside and screened with walls, trellises, or shrubbery for vegetable and "picking" gardens.