Pennisetum x advena 'Rubrum' -- Nevada

Pennisetum setaceum is native to northern Africa. This species has been reported to have spread to Australia, New Zealand, and Micronesia. It is reported to have escaped cultivation and become naturalized in U.S. Southwest and Hawaii. However the cultivar P. x advena is reported to be sterile which would prevent the variety from becoming naturalized.

Pennisetum setaceum has been reported as being naturalized in the south west U.S. but will not persist in areas where the temperature falls below zero for any period of time (Wipff and Veldkamp, 1999). The species cold hardiness zones range from 8-11 (Monrovia) which match southern Nevada's warm desert climate. This species has been reported to occur in Hawaii, California, Texas and southern Florida but the cultivar P. x advena has not been reported to ever have escaped cultivation.

Pennisetum setaceum is reported to be invasive outside of its native range in Northern Africa. However due to the sterile nature of the cultivar P. x advena this particular variety is not considered to be invasive.

Pennisetum setaceum is reported to be invasive outside of its native range in Northern Africa in similar climates (see Climate Match map). However due to the sterile nature of the cultivar P. advena this particular variety is not considered to be invasive anywhere to date.

Pennisetum x advena "Rubrum" is a cultivar of P. setaceum, an invasive species in California, Nevada, Arizona and Hawaii. P. setaceum is also invasive in Australia, New Zealand, South Africa and southern parts of Europe. P. setaceum is considered a noxious weed in Nevada and Hawaii in the U.S., and noxious in New Zealand, New South Wales, and Queensland of Australia and is included on the noxious weed watch list in New Mexico. P. setaceum occurs in warm and arid landscapes that match southern Nevada's warm desert climate. There is a study that suggest the invasive species P. setaceum might have the potential to cross breed with P. setaceum x rubrum and create a hybrid plant that can produce viable seeds. The study conducted on this has not yet been released and is therefore not available to attach to this evaluation.

The parent of P. x advena, Pennisetum setaceum, is not found predominately in the region of concern which is Nevada (see Climate Match map). The species is reported to grow best in USDA hardiness zones 9-10 (Missouri Botanical Garden) but has been listed to grow in zones 8-11 (Monrovia). Areas in which the species is found predominately include parts of California, Florida, Arizona and Texas. The southern Nevada warm desert climate does match does match USDA hardiness zones and similar climates in southern California and Arizona but is only a portion of the region of concern. The cultivar P. x advena has been reported to not withstand freezing temperatures for any period of time (Wipff 1999). The species has been used as an ornamental plant in Northern Nevada which reaches temperatures cold enough to freeze this plant during the winter.

Pennisetum x advena grows to 3-5 feet high and spreads to a width of 2-4 feet. It is drought tolerant and grows best under full sun conditions. There is no current data to support that Pennisetum x advena escapes cultivation even under the best conditions and displaces native plant communities as it rarely seeds out.

Pennisetum setaceum is been reported to alter fire cycles in Hawaii. It is suggested that the species may convert forest communities into grasslands. However P. x advena is reported to be sterile and has not been reported to have escaped cultivation.

No current evidence to suggest Pennisetum x advena is a health risk to humans or animals, but some farmers suggest fountain grass species in general provide little nutritious value to livestock and livestock will choose other plant species for grazing if possible.

No current evidence to suggest Pennisetum advena escapes cultivation to dominate landscapes and produce impenetrable thickets. The discrete clumping habit of it and its parent species do not lend themselves to being inpenetrable.

Pennisetum advena is considered sterile as it does not produce viable seeds. It can be propagated by digging up the parent plant and dividing it and replanting it. There is no further evidence to show it can reproduce on its own vegetatively.

Pennisetum advena does not propagate on its own from detached fragments.

Pennisetum advena is considered sterile and is reported to rarely produce seed if ever. Current research is in progress on the ability of P. x advena plants to produce viable seeds when crossed with P. setaceum, and this question will be revisited if results suggest that they do.

Pennisetum advena is reported to be sterile.

All information found on Pennisetum advena's seed production mentioned that the cultivar was sterile and did not produce viable seed. No information was found on environmental conditions required for seed germination.

Pennisetum advena is reported to be sterile and is reported to rarely seed out if ever.

Pennisetum advena is reported to be sterile and rarely produces seed if ever.

The seed head of Pennisetum setaceum can attach itself to fur. Researchers believe that the species can be introduced by domestic animals transported into the country. However, because seed material of the cultivar P. x advena is considered sterile, long-distance dispersal should not occur.

Pennisetum setaceum has been reported to be established along river banks in southern Nevada. The only seed source for those plants would have been from ornamental plantings of the species at nearby casino properties. However, because seed material of the cultivar P. advena is considered sterile, there should be no long-distance dispersal of this species.

The seed head of Pennisetum setaceum can attach itself to clothing. However P. advena is reported to produce sterile seeds.