**Piptatherum miliaceum (L.) Barkworth (Poaceae)**

**Smilo grass, Rice Grass**

**Description**. Tufted perennials, 6-15 dm tall, stems erect, decumbent
at the base, glabrous. Leaves alternate, mostly cauline; ligules 1.5-3
mm long, apices rounded to truncate; auricles absent; sheaths glabrous,
persistent; blades linear, flat, 3-10 mm wide, minutely scabrous.
Inflorescence a terminal, open panicle 15-30 cm long, the branches
whorled, spreading to ascending. Spikelets composed of 1 floret, the
glumes 2.5-4 mm long, subequal, lanceolate, 3-nerved, glabrous to
minutely scabrous, the apices acuminate; lemma 2-3 mm long,
oblong-elliptic, 3-nerved, smooth, shiny, the apex rounded, minutely
bilobed, awned, the awn 2-3.5 mm long, straight, deciduous. In
California, flowering from April to September. (Barkworth 1993, Chapman
1991, Hitchcock 1944, Holmgren and Holmgren 1977, Munz 1959, Tutin
1980).

Synonym:*Oryzopsis miliacea* (L.) Aschers. and Schweinf.

**Geographic distribution**. A native of southern Burope, smilo grass
has been reported as waif in Great Britain and has become naturalized in
California, western Nevada, and Australia.

(Barkworth 1993, Clapham et al. 1962, Holmgren and Holmgren 1977, Munz
1959). Apparently

it has not become established elsewhere in the world.

According to Robbins (1940), Smilo grass was first collected around the
turn of the 19th century (Los Angeles in 1896, Santa Barbara and
Monrovia in 1916) and had been reported mostly from urban waste areas in
urban southern California by 1940. It has been reported from all four
northern California Channel Islands (Junak et al. 1997) and is now known
from most southern California counties (Anonymous 1998, Barkworth 1993).

**Reproductive and vegetative biology**. Like most species of grasses,
smilo grass is wind-pollinated (Proctor et al. 1996). No literature was
found that discussed aspects of its reproductive and vegetative biology.

**Ecological distribution**. Smilo gras has been reported from dry or
moist sites in disturbed areas, roadsides, and ditches (Barkworth 1993,
Munz 1959, Robbins 1940). It has been used in the revegetation of
frequently burned chaparral (Hanes 1990). Zavas et al. (1996) studied
ecotypes of *Piptapherum miliaceum* that included strains resistant to
aluminum. In semi-arid Spain, smilo grass showed higher growth rates
when infected with mycorrhizal fungi compared to uninfected plants
(Roldan-Fajardo 1994).

**Weed status**. Smilo grass is not considered a noxious weed in
agricultural or horticultural practice, at least at a global level (not
listed by Holm et al. 1977), nor is it listed for the United States in
Lorenzi and Jeffery (1987). However, it is considered a noxious weed by
the State Dept. of Food and Agriculture (Anonymous 1996), especially in
southern California riparian habitats.

**Microbial and insect pathogens**. No literature was found that
reported smilo grass as a host to microbial or insect pathogens.

**Herbicide control**. No literature was found that reported use of
herbicides to control smilo grass.

**Literature Cited**

Anonymous. 1996. Exotic pest plants of greatest ecological concern in
California as of August 1996. California Exotic Pest Plant Council. 8
pp.

Anonymous. 1998. USDA Plants Database, Baton Rouge, LA. URL =
usda.plants.gov. Barkworth, M. 1993. *Piptatherum*. pp.1282-1283. In
Hickman, 3. (ed.). The Jepson

manual: vascular plants of California. University of California Press,
Berkeley. 1400

pp.

Clapham, A., T. Tutin, and E. Warburg. 1962. Flora of the British Isles.
Cambridge University Press, Cambridge. 1269 pp.

Hanes, T. 1990. California chaparral. pp.417-469. In Barbour, M. and J.
Major. (eds.). Terrestrial vegetation of California. Special Publication
No.9. California Native Plant Society, Sacramento, California. 1002 pp.

Hitchcock, A. 1944. Poaceae. pp.103-255. In Abrams, L. Illustrated flora
of the Pacific States. 1. Ophioglossaceae to Aristolochiaceae, Stanford
University Press, Stanford, California. 538 pp.

Holm, L., D. Plucknett, J. Pancho, and J. Herberger. 1977. The world\'s
worst weeds:

distribution and ecology. University Press of Hawaii, Honolulu. 609 pp.

Holmgren, A. and N. Holmgren. 1977. Poaceae. pp. 175-462. In Cronquist
et al. Intermountain Flora. Volume 6. The monocotyledons. New York
Botanical Garden and Coplumbia

University Press, New York. 584 p.

Junak, S., S. Chaney, R. Philbrick, and R. Clark. 1997. A checklist of
vascular plants of Channel Islands National Park. Southwest Parks and
Monuments Association, Tucson, AZ. 43 pp.

Lorenzi, H. and L. Jeffery. 1987. Weeds of the United States and their
control. Van Nostrand Company, New York. 355 pp.

Munz, P.1959. A flora of California. University of California Press,
Berkeley. 1681 pp.

Proctor, M., P. Yeo, and A. Lack. 1996. The natural history of
pollination. Timber Press, Portland, Oregon. 479 pp.

Roldan-Fajardo, B. 1994. Effect of indigenous arbuscular mycorrhizal
endophytes on the development of six wild plants colonizing a semi-arid
area in south-east Spain. New Phytologist. 127:115-121.

Tutin, T. 1980. *Piptatherum*. pp.246-247. In Tutin et al. (eds). Flora
Europaea. Volume

5\. Alismataceae to Orchidaceae. Cambridge University Press, Cambridge.
452 pp.

Zavas, T, L. Symeonidis, and S. Karataglis. 1996. Responses to aluminium
toxicity effects of two populations of *Piptatherum miliaceum* (L.)
Cosson. Journal of Agronomy and Crop Science. 177: 25-32.