The greenhouse range and the main structure completed in 1915, provide laboratory and office space to the Department of Horticulture at Iowa State University. The greenhouse range was built with 27,000 square feet and 3750 square feet was added and opened in 1980. This is separated into two areas designated Old Range and New Range. The Old Range was built in 1915 and re-glazed in 1975. It consists of ten 25ft. x 75ft. houses plus three greenhouses reserved for a conservatory and plant collection area. The plant collection consists of two houses with benches containing over 400 species of tropical and sub-tropical plants organized and labeled alphabetically within family groups. Between these houses is the center conservatory where these plants are grown in a natural setting with ponds and water -falls. The New Range built in 1980, consists of six 19ft. x 25ft. houses with concrete floors. Each house is equipped with automatic vents, exhaust fans, chilled water cooling and steam heat. Supplemental lighting and de-ionized water are available in most houses. The smaller houses are used for faculty and graduate student research. This model was completed by Kurtis Wolgast and modified by Benjamin Schwartz.