under these conditions. For example, many Australian plants are particularly sensitive to phosphorus. Many native plants are adapted to, and benefit from, periodic wildfires that occurred before and during pre-modern settlement. These fires can be simulated in the garden by either "high mowing" or a controlled burn every few years. Many weeds in an area are usually the result of imported plants. These plants become invasive because there are no natural controls such as disease, weather, or fauna in their new environment. They take over native habitats, reducing shelter and food for local fauna. Using local provenance plants increases the biodiversity of and is important for the health of a region's overall ecology. Much of the wild areas have been destroyed to make room for urban development. Housing developments have replaced native habitats with ornamental plants and lawns, pushing the wildland–urban interface further out. While development won't be stopped, gardeners can keep wild areas and green spaces filled with native species on their lots and in their communities. Despite this, there are usually plenty of indigenous or native plants which will grow and thrive in the area one is trying to establish a native garden. Native plants The use of native plants in a garden or landscape can both preserve and protect natural ecosystems, and reduce the amount of care and energy required to maintain a healthy garden or landscape. Native plants are adapted to the local climate and geology, and often require less maintenance than exotic species. Native plants also support populations of native birds, insects, and other animals that they coevolved with, thus promoting a healthy community of organisms. Plants in a garden or maintained landscape often form a source population from which plants can colonize new areas. Avoiding the use of invasive species helps to prevent such plants from establishing new populations. Similarly, the use of native species can provide a valuable source to help these plants colonise new areas. Some non-native species can form an ecological trap in which native species are lured into an environment that appears attractive but is poorly suited to them. However, in Britain research by the University of Sheffield as part of the BUGS project (Biodiversity in Urban Gardens in Sheffield) has revealed that for many invertebratesthe majority of wild animals in most gardensit is not just native plants which can sustain them. The findings were published in popular form in