The
plant division
Gnetophyta or gnetophytes comprise three related families of
woody plants grouped in the
gymnosperms. The gnetophytes differ from other gymnosperms in having
vessel elements as in the
flowering plants (
Angiosperms or
Magnoliophytes).
The living Gnetophyta comprise three genera
Plants of the genus Ephedra are known as jointfirs because they have long slender branches which bear tiny scale-like leaves at their nodes. Ephedra has been traditionally used as a stimulant, but is a controlled substance today in many jurisdictions because of the risk of harmful or even fatal overdosing.
In some classifications all three genera are placed in a single order (Gnetales) but in others distributed among three orders, each containing a single family and genus.
