La Selva has over 1,500 hectares of old growth and second growth forests with an extensive trail system and well-equipped laboratories. Las Cruces Biological Station located at 1,200 meters elevation has a world-class plant collection in the Wilson Botanical Garden and an associated 160 hectare tract of old growth rain forest. The station maintains shade houses and a laboratory. Las Cruces is located in the southern part of the country near the Panamanian border and La Amistad National Park. Palo Verde Biological Station is in the heart of Palo Verde National Park, located in dry forest in the northwestern province of Guanacaste.
Some sites are in remote areas with no electricity or telephones.
Living conditions are cramped so students need to be flexible in their personal needs. On the first day at each of the several locations, orientation walks introduce small groups of students to this site. The walks focus on the plants and animals of the habitat and include discussion of major ecological factors, such as biotic interactions, climate, and soils, that shape local ecosystems. The history of the site and local conservation issues are also explored. Beginning on the second day at each site, students break into small groups to participate in short field problems designed by faculty in consultation with the students.