rounded or spreading growth habit of the tree crown (contrast with excurrent).
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In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem. A "decurrent branching habit" is a plant form common for shrubs and most angiosperm trees, contrasted with the excurrent or "cone-shaped crown" common among many gymnosperms. The decurrent habit is characterized by having weak apical dominance that eventually produces a rounded or spreading tree crown. Examples of trees with decurrent habit are most hardwood trees: oak, hickory, maple, etc.
In mycology, the term is most often applied to the hymenophore of a basidiocarp (such as the lamellae or "gills" of a mushroom or the "pores" of a bracket fungus) when it is broadly attached to and extends down the stipe.