Panic grass, Panicum L., is a large genus in the grass family
and it is difficult taxonomically thus causing panic among those just starting
to learn about it.There are about 450
species currently in the mostly tropical genus, of these about 50 are reported
in the United States and territories with 16 of those in Alabama including 4
that are exotic.This seems manageable,
but the genus was much larger with at least 623 described species that are now
synonymous with species in 22 other genera.The most familiar of these are Bermuda
grass, Cynodondactylon
(L.) Pers., several species of crabgrass, Digitaria Haller,
and essentially the entire genus of rosette grass, Dichanthelium(Hitchc. & Chase) Gould.
The introduced species of panic
grass reported in Alabama
are blue panicum, Panicumantidotale Retz., Berg's panicgrass,
P.bergii Arechav., broomcorn millet, P.miliaceum L.,
and torpedo grass, P.repens
L., three of which are considered invasive.The most important of these is broomcorn because it is one of the most important of the
grains called millet.This is also the millet/pannag
mentioned in the Bible.Reasons for the importance of millet is that it will grow in hotter drier areas where corn/maize, Zea mays
L., will not grow, and that millet does
not have gluten although this generally limits its use to flat breads; both of reasons apply to sorghum, Sorghum bicolor (L.) Moench, which is sometimes called millet.
The most important native species
is switchgrass, P.virgatum L., because it is touted as a potential source of biofuel.This is because it is a perennial that grows
very fast even in places were other crops will not grow. The downside to use it for a renewable energy source
is that the technology to extract ethanol from cellulose has yet to be developed
sufficiently to be economically viable.One of the difficulties is separating the cellulose to be converted to alcohol from the lignin that binds it together.
