12 Easy Grasses

         (12 plants)

Rattlesnake grass
Here's a guide to get you started with grasses - 12 distinctive grasses you'll see fairly frequently in Marin County.

Once you learn how to identify these, you'll have an eye for patterns to look for as you investigate more grasses.

Thanks to Phil Greer for providing information for this guide.

Have fun!

Grass Family

Rattlesnake Grass
Briza maxima
  • CA Bloom Mar - May
  • Distinctive flowers have sections like the tail of a rattlesnake.
  • Thin stems and large flower structures cause the plant to move in a light breezes.
  • You'll find Rattlesnake Grass in open meadows, on hills, and at the margins of woods.
  • Annual grass
  • Not CA native
  • Somewhat Invasive

Smooth nodding flower clusters are diagnostic.

Closeup of flowers. Pale green with purple shoulders.

Flowers turn straw color and fall apart with age.
Wild Oats
Avena fatua
  • CA Bloom Mar - Jun
  • Nodding green flowers soon turn to brown seed husks.
  • Found in large stands on hillsides. You can tell them from a distance by their large, upside-down-V flower structures.
  • An annual grass.
  • Stems stand erect and tall.
  • Not CA native.
  • Moderately Invasive

Flowers hang down from erect stems.

Seed covers are in a downward V, with stringy awns hanging below.

Seed covers overlap.
Dogtail Grass
Cynosurus echinatus
  • CA Bloom May - Jul
  • Found in disturbed areas.
  • Flowers in a bunch at the top of the stem form a "tail".
  • Annual
  • Not CA native
  • Moderately Invasive

Bristly chubby flower clusters. Plants can be 3 feet tall.

Stiffly spiky flower clusters are diagnostic.

Long- awned flowers, denser on one side. Fairly wide leaves.
Velvet Grass
Holcus lanatus

Soft, arching flower clusters.

Clusters start spike-like, purplish, and expand and fade to straw color.

In full bloom, note paler color.
Foxtail Barley
Hordeum murinum ssp. leporinum
  • CA Bloom Apr - Jul
  • An annual grass.
  • Disturbed areas.
  • Not CA native

Dense arching clusters bristling with awns.

Closeup of flowers showing fairly wide, slightly bluish leaves.

Maturing flowers turn brownish and shatter.
Purple Needlegrass
Stipa pulchra
  • Height 2 - 3 ft.
  • CA Bloom Mar - May
  • Purple flowers with long needle-like awns, often drooping.
  • A perennial grass.
  • Widespread, found on slopes.
  • CA native. The California state grass.

Grows to 3 feet. Flowers extend above the leaves.

Flowers are purplish with long needle-like awns.

Closeup of flower cluster.
Bromus diandrus

Emerging flowers. Note fairly wide leaves. At this stage, closely resembles our native B. carinatus.

At maturity, develops distinctive nodding form. Note very long needle-like awns.

Hairy stalks. Often a single stem. Fairly wide leaf.
Panic Veldtgrass
Ehrharta erecta
  • CA Bloom Mar - Jun mostly, but can bloom other times of the year.
  • Grows rapidly - has been used in dune restoration.
  • Seeds form in a few weeks and grow year-round.
  • Not CA native.
  • Moderately Invasive

Wide-leaved grass, generally growing to a couple of feet.

Grass shows many parallel veins. Notice the long wispy hairs at the joints.

Seed is over an inch long. Click this picture to see eyelash-like hairs at the base of the flower.
Italian Ryegrass
Festuca perennis
  • CA Bloom May - Sep
  • Flowers alternate all the way up the stem.
  • Flowers attach at indented places on the stem, giving a bumpy look
  • Grows erect, to several feet tall.
  • An annual grass, despite it's species name of perennis.
  • Grows in open areas.
  • Not CA native
  • Moderately Invasive

This grass stands erect and has flowers alternating up the stem.

Notice how each flower fits in an indent in the stem.

Here the flowers are opening at maturity, to let the fruit fall out.
Blue Wild Rye
Elymus glaucus ssp. glaucus
  • Height 2 - 5 ft.
  • CA Bloom May - Jul
  • Found at the margins of woods.
  • A perennial, many stems grow from a common root system that develops over the years.
  • CA native

Blue Wild Rye is a tall bunchgrass, with many stems growing from a common root system.

Closeup of flowers, showing medium-length awns. The whites spots are dried anthers.

Note fairly wide, soft green leaves. There is a sheath around the stem below where the leaf meets it.
A Rush and a Sedge
    Here are two grass-like plants that are technically not grasses.

Pacific Rush
Juncus effusus ssp. pacificus
  • CA Bloom Jun - Aug
  • Rushes have solid cylindrical stems. Grass stems are hollow.
  • Like many rushes, Pacific Rush is found in moist areas.
  • This is a perennial plant - notice the substantial stems leading to a permanent root system.
  • CA native

This rush has many straight stems widening out from a common base. Flowers appear on the side of the stem, part way up.

Small reddish-brown flower clusters along the stem make rushes easy to spot.

Narrow round stems and leaves come out of a common base which lasts many years.
Tall Flatsedge
Cyperus eragrostis
  • CA Bloom May - Sep
  • Sedges have edges. Their triangular, erect stems distinguish them from grasses and rushes.
  • Tall Flatsedge has Long thin leaves at the bottom of the plant, and also near the top. The top leaves stand out horizontally from the stem.
  • Green spiky flowers cluster at the top of the stem, just above the top leaves.
  • CA native

Stems are 3-sided with sharp edges. Sedges have edges.

Flowers bunch at the top of the stem.

Tall Flatsedge stands several feet tall, with flat, folded leaves sticking out from the plant.