US Sierra Nevada Mixed conifer forests in the United States Sierra Nevada used to have fire return intervals that ranged from 5 years up to 300 years, depending on the locale. Lower elevations tended to have more frequent fire return intervals, whilst higher and wetter sites saw longer intervals between fires. Native Americans tended to set fires during fall and winter, and land at higher elevations was generally occupied by Native Americans only during the summer. Finnish boreal forests The decline of habitat area and quality has caused many species populations to be red-listed by the International Union for Conservation of Nature. According to a study on forest management of Finnish boreal forests, improving the habitat quality of areas outside reserves can help in conservation efforts of endangered deadwood-dependent beetles. These beetles and various types of fungi both need dead trees in order to survive. Old growth forests can provide this particular habitat. However, most Fennoscandian boreal forested areas are used for timber and therefore are unprotected. The use of controlled burning and tree retention of a forested area with deadwood was studied and its effect on the endangered beetles. The study found that after the first year of management the number of species increased in abundance and richness compared to pre-fire treatment. The abundance of beetles continued to increase the following year in sites where tree retention was high and deadwood was abundant. The correlation between forest fire management and increased beetle populations shows a key to conserving these red-listed species. Australian eucalypt forests Much of the old growth eucalypt forest in Australia is designated for conservation. Management of these forests is important because species like Eucalyptus grandis rely on fire to survive. There are a few eucalypt species that do not have a lignotuber, a root swelling structure that contains buds where new shoots can then sprout. During a fire a lignotuber is helpful in the reestablishment of the plant. Because some eucalypts do not have this particular mechanism, forest fire management can be helpful by creating rich soil, killing competitors, and allowing seeds to be released. Management policies United States Fire policy in the United States involves the federal government, individual state governments, tribal governments, interest groups, and the general public. The new federal outlook on fire policy parallels advances in ecology and is moving towards the view that many ecosystems depend on disturbance for their diversity