Panicum hillmanii
Hillman's panic grass
(c) Augustin Soulard, some rights reserved (CC BY) · licence
Family: Poaceae · Type: Grass · Not Native
Panicum hillmanii (Hillman's panic grass) is a non-native California grass in the Poaceae family, recognized by crescent-shaped scars at floret base.
Hillman's panic grass is a naturalized annual grass found in northern California Coast Ranges, Sierra Nevada foothills, Sierra Nevada, Central Valley, southern California, Peninsular Ranges, and desert regions in disturbed areas and roadsides at elevations below 1,200 meters. Flowering from May to October, this grass produces pale green to green-brown spikelets approximately 2.3 to 3 millimeters long with delicate branching inflorescences. Growing with erect stems 20 to 70 centimeters tall, it has rough-hairy leaf sheaths and slender green stems. Its leaf blades are 8 to 15 centimeters long, 4 to 12 millimeters wide, with short soft hairs on the upper surface and ciliate membrane ligules. The spikelets have distinctive lower glumes 1 to 1.5 millimeters long with 3 to 5 veins and acute tips.
Identification and appearance
Key characters: 11 sympatric species; key feature is crescent-shaped scars at floret base
Habitat and range
Habitat: Disturbed areas, roadsides, fields
Elevation: < 1200 m
Outside California: native to Great Plains
Bloom period
Panicum hillmanii blooms May-Oct.
How to tell it apart
vs Deschampsia: Panicum has thick rigid lemmas and well-developed lower glumes; hairgrass has thin awned florets and tiny glumes.; vs Dichanthelium: Panicum has a single flowering period; rosette grass produces two distinct flower types (spring and summer).; vs Hilaria: Panicum has single spikelets on branches; curly mesquite has spikelets in clusters of three along a spike.; vs Sorghum: Panicum has single spikelets throughout panicle; sorghum has three-spikelet groups at branch tips.; vs Echinochloa: Panicum has a membranous ligule and panicle; barnyard grass lacks a ligule and has bristly branches.
Frequently asked questions
Is Panicum hillmanii native to California?
No. Panicum hillmanii is not native to California (recorded as not native).
When does Panicum hillmanii bloom?
Panicum hillmanii blooms May-Oct.
What plant family does Panicum hillmanii belong to?
Panicum hillmanii is in the Poaceae family, genus Panicum.
What habitat does Panicum hillmanii grow in?
Panicum hillmanii grows in Disturbed areas, roadsides, fields.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.