Decurrent

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Decurrent leaves in Common Mullein (Verbascum thapsus)
Decurrent leaves in Common Mullein (Verbascum thapsus)

Decurrent is a botany term used to describe plant parts that extend downward, most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem.

In mycology decurrent describes lamellae (the gills of a mushroom) that are broadly attached and extend down the stipe of the mushroom.

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.[1] 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. [2]

[edit] References

  1. ^ Harris, RW (April 1980). "Structural Development of Trees". Journal of Arboriculture 6 (4): 105–107. International Society of Arboriculture. 
  2. ^ Claud L. Brown, Robert G. McAlpine, Paul P. Kormanik, "Apical Dominance and Form in Woody Plants: A Reappraisal", American Journal of Botany, Vol. 54, No. 2 (Feb., 1967), pp. 153-162, doi:10.2307/2440793