Removal of crooked, forked, or diseased trees from a forest in which tree diameters are 5 in (13 cm) or larger. In forests where trees are smaller, the same process is called cleaning or weeding. Both have the objective of improving species composition, stem quality and/or growth rate of the forest. Straight, healthy, vigorous trees of the desired species are favored. By discriminating against certain tree species and eliminating trees with cavities or insect problems, improvement cuts can reduce the variety of habitats and thereby diminish biodiversity . An improvement cut is the initial step to prepare a neglected or unmanaged stand for future harvest.