Grasses and Grasslike Plants1 & 2

Grasses (Family: Poaceae)

Dunegrass & Beachgrass
Among the many true grasses (family Poaceae) found on dunes, two large species stand out. These are the dunegrass, Elymus mollis, and the beachgrass, Ammophila arenaria. Elymus is a native, and it was the chief sand binder on Pacific coast dunes before Ammophila was introduced from Europe about a hundred years ago.

Ammophila is more effective than Elymus in binding sand, and this seems to be the reason that foredunes in most parts of the region under consideration are higher than they once were

Both Elymus and Ammophila are perennials that have creeping rhizomes. Both are also relatively large grasses, their flowering spikes reaching a height of more than one meter. They are readily distinguished from one another, however. The leaf blades of Elymus are usually about one centimeter wide, and the plants as a whole have a decidedly grayish tinge. The leaf blades of Ammophila are rarely more than four millimeters wide, and the plants are mostly yellowish green.

Saltgrass
The most prevalent of the true grasses is saltgrass, Distichlis spicata, which reaches a height of about 20 centimeters. It spreads by runners and forms dense stands wherever it grows.

Saltgrass (Distichlis spicata) Photo Credit: NOAA National Estuarine Research Reserve Collection

Smooth Cordgrass
Smooth Cordgrass (Spartina alterniflora), native to the Atlantic coast and the Gulf of Mexico, is similar to S. foliosa (Pacific coast native) in appearance and in the way it spreads. It was introduced to Willapa Bay, in southern Washington, many years ago, and is now firmly established there as well as in the La Conner Slough. It is considered a nuisance species.

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Salt Rush (Family: Juncaceae)

Rushes (family Juncaceae) are typical of low spots where the water table is not far below the surface. Salt rush (Juncus lesueurii) is probably the most regularly encountered species on the Pacific coast. It is sometimes found in situations that seem to be almost bone dry, but excavation will generally reveal appreciable moisture around the roots and creeping rhizomes. In dunes, this species reaches a height of about 25 centimeters.

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Rhubarb (Family: Polygonaceae)

Beach Knotweed
Beach Knotweed, Polygonum paronychia, ranges from near Monterey to British Columbia. It is an unimpressive sprawler whose stems radiate away from a woody root. The narrow leaves, with downcurved and inrolled margins, are about two centimeters long. The flowers are inconspicuous, but they are worth a look with a magnifying glass because their white or pale pink sepals (there are no petals) are attractively marked with featherlike green "veins." A conspicuous feature of this plant is the papery sheaths that cover the leaf buds; these persist even after the leaves are fully developed.

Willow Dock
Rumex salicifolius, called willow dock, is a close relative of rhubarb and several weedy species of dock that grow in gardens, fields, and along roadsides. The stems may be floppy or upright, but they are generally under one meter long. The leaves, with blades from about 6 to 13 centimeters long and 2 centimeters wide, grow from the stems in groups. The small greenish or whitish flowers are crowded into oblong clusters that arise from among some of the leaves. This plant grows on dunes and in other sandy or gravelly maritime situations from southern California to British Columbia. It is not limited to coastal areas, however, and its distribution includes much of North America. It is an extremely variable species, and in some books dealing with the flora of the Pacific coast, the seaside form, with rather fleshy leaves, is called R. crassus, or R. salicifolius variety crassus.

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Verbena (Family: Nyctaginaceae)

Sand-verbenas are not really verbenas; they belong to the same family as cultivated four-o'clocks. Only one species is widespread within the range covered by this characterization. This is the yellow sand-verbena, Abronia latifolia. Although found primarily along the outer coast, from Vancouver Island to southern California, it occurs in suitably sandy situations in the San Juan Archipelago and even in Puget Sound. It is a prostrate perennial that spreads into large mats. The flower heads, about three centimeters across, are produced in profusion throughout the summer. The bright yellow color of the individual flowers, each about five millimeters across, resides in the trumpetlike calyces; there are no petals. The whole plant is rather gummy and generally has considerable sand sticking to it.

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Pinks (Family: Caryophyllaceae)

Sea Purslane
Honkenya peploides, sea purslane, is a rather succulent, mat-forming perennial with opposite leaves that are mostly one to two centimeters long. The small flowers are borne singly in the leaf axils. They generally have five petals, which are whitish and inconspicuous because they do not stick out beyond the sepals. The fruit is almost globular. The range of this plant, which commonly grows to a height of about 20 centimeters, is from Alaska to northern Oregon.

Sand Spurreys
Spergularia canadensis, one of the so-called sand spurreys, is an annual belonging to the family Caryophyllaceae, which includes carnations and pinks. It tends to be concentrated at a level slightly above that where Salicornia is most abundant, but it may be mixed with the latter. The five-petaled flowers, about seven millimeters across, are white or pale pink. The leaves, strictly opposite and mostly about two centimeters long, are only about one millimeter wide, and they are slightly fleshy. The whole plant, in fact, is somewhat succulent. The height does not often exceed 15 centimeters. This species occurs from Alaska to northern California. A closely related species, S. macrotheca, typically inhabits drier ground; it will be discussed later.

Spergularia macrotheca or Sticky Sand-Spurrey resembles S. canadensis. It is, however, a perennial that produces a stout taproot, and it is also rather hairy. The flowers, not quite one centimeter across, have five petals and ten stamens. The petals are usually bright pink, but in some populations most or all of the plants have white flowers. The range of this species extends from British Columbia to Baja California. It is found not only close to salt marshes, but also on bluffs that overlook the sea.

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Sea Rocket (Family: Brassicaceae)

Sea rocket, Cakile edentula, is an annual that was introduced from the Atlantic coast during the nineteenth century. It is now found on dunes and backshores of sandy beaches. It is an almost succulent plant that forms multi-branched, sprawling growths that are often more than one meter across. Its membership in the mustard family is confirmed by the following combination of flower characters: four petals, six stamens (two of which are shorter than the rest), and a seed pod that originates above the bases of the petals rather than below them. The petals, about six millimeters long, are pale purple. The seed pods are fleshy and pinched into unequal halves by a slight constriction. The larger leaves, generally four to six centimeters long, have wavy margins.

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Beach Strawberry (Family: Rosaceae)

The beach strawberry, Fragaria chiloensis, resembles the cultivated strawberry and native inland species. It hugs the sandy ground in which it is rooted, however, and is not likely to raise its flowers more than about three centimeters. The leaflets are dark green and shiny above, silky below. The flowers are of two types: those that have only stamens for producing pollen, and those that have only pistils that collectively form the fruit. As a rule, the pistillate and staminate flowers are on separate plants. The beach strawberry has a wide geographic distribution. Besides being found from central California to Alaska, it occurs on the Pacific coast of South America (its specific name alludes to the fact that an early collection came from the island of Chiloe, in Chile), and also in Hawaii. It has figured in the parentage of some strains of the cultivated strawberry.

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Legumes (Family: Fabaceae or Leguminosae)

The beach pea, Lathyrus japonicus, occurs throughout the range covered. It is found in Puget Sound, in the San Juan Archipelago, and in other relatively protected situations, as well as along the open coast. Its favorite habitat is the backshore of a beach where there is a fair amount of driftwood for it to clamber over. The leaves have up to a dozen leaflets in addition to the tendrils. The flowers, of which there are generally several, are about two centimeters long and typically deep pink suffused with purple.

The bush lupine, Lupinus arboreus, is a shrubby species native to the region between southern California and central Oregon. It has been introduced farther north, however, and is now common in some places around Puget Sound and in the San Juan Archipelago. It grows not only on backshores and sand dunes, but also a little farther back from the beach. This species is regularly about one meter high, and the typical yellow-flowered form is a lovely sight when it is in full bloom in late spring or early summer. There are forms with pale blue or pale lilac flowers, and these could be confused with another coastal beach lupine, L. chamissonis. This species differs from L. arboreus, however, in having hairs on the back of the upper petal, which is called the "banner." It is more characteristic of what may be called "real dirt" than of sand dunes.

Bush Lupine (Lupinus sp.) Photo Credit: National Park Service

Lupinus littoralis, the seashore lupine, is a low creeper found from northern California to British Columbia. It is not restricted to the open coast, and there are nice colonies of it on sandy beaches and bluffs in the San Juan Archipelago. This species is perennial, but it dies back each autumn. The leaves have five to nine leaflets, and these, like almost all parts of the plant, are rather hairy. The blue or lilac flowers, mostly about one centimeter across, are concentrated in dense, upright spikes. The seed pods reach a length of about three centimeters. This is the only lupine, other than the much larger L. arboreus, that is likely to be found on sandy beaches right next to salt water.

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Beach Evening Primrose (Family: Onagraceae)

The beach evening primrose, Oenothera cheiranthifolia (or Camissonia cheiranthifolia) is a common perennial of dunes and sandy soils along the open coast. From a crown of basal leaves, it sends out several to many stems that may spread out to form a mat that is more than a meter across. The flowers, with four bright yellow petals, are generally about 1.5 centimeters in diameter. They open in the morning, instead of in the evening the way many other species of Oenothera do. As the flowers age, the petals usually become reddish.

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American Glehnia (Family: Apiaceae)

American Glehnia (Glehnia leiocarpa) is a compact, slightly succulent plant. Its leaves, up to about 15 centimeters long, are deeply divided into several leaflets, each of which may have secondary lobes. The bases of the leaf petioles, often buried in sand, clasp the main stem. The foliage is rather hairy or woolly, especially on the underside. The numerous small flowers are packed into several tight clusters that collectively form a nearly flat-topped inflorescence of the type that is characteristic of the carrot and its allies. The flower stalk sticks up only a few centimeters above the leaves. Glehnia is common on the backshores of sandy beaches from British Columbia to southern Oregon, but it gradually drops out in northern California.

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Seaside Heliotrope (Family: Boraginaceae)

Heliotrope, Heliotropium curassavicum, belongs to the family that also claims the wildflowers called fiddleneck and popcorn flower and the garden herb called comfrey. It is not restricted to maritime situations. At the borders of salt marshes it is inclined to grow coarser and taller--up to about 30 or 40 centimeters high--than it does on the backshores of beaches, where it hugs the sand. Regardless of where it grows, it is an evergreen perennial and its foliage is rather fleshy, smooth, and grayish green. The flowers, crowded into slightly curved clusters, are about five or six millimeters across. The five petals are white at their extremities, but the throat of the tube into which they are fused has considerable yellow in it.

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Seaside Plantain (Family: Plantaginaceae)

Seaside plantain, Plantago maritima subspecies juncoides, occurs at the edges of salt marshes, along sandy beaches, and on cliffs and bluffs close to the shore. It is an evergreen perennial with narrow, fleshy basal leaves whose shape and length vary according to the exact habitat. In general, however, the leaves are 5 to 15 centimeters long and at least five times as long as wide. As in the weedy plantains introduced from Europe, the greenish, four-petaled flowers are concentrated in spikes raised up on leafless stalks. This species occurs throughout the range, and is found as far north as Alaska.

Seaside Plantain (Plantago maritima) Photo Credit: NOAA National Estuarine Research Reserve Collection

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Asters (Family: Asteraceae)

Silver Beachweed
Silver beachweed, Ambrosia chamissonis (Franseria chamissonis), is a mat-forming perennial whose crinkly edged leaf blades, up to about four centimeters long, are so densely clothed with silky hairs that they are almost white. The heads of seed-producing flowers are situated in the axils of the upper leaves, and their bracts are spiny enough to form burs. The heads in which the pollen-producing flowers are concentrated are in a terminal spike. The range of this species extends from central California to British Columbia.

Growing with A. chamissonis--or replacing it completely in some areas, especially along the coast of Oregon, Washington, and British Columbia – is a subspecies called bipinnatisecta. Its leaves are mostly gray green, for they are less hairy than those of silvery beachweed and they are divided into leaflets that are divided once and sometimes twice again. The organization of the flower heads is substantially the same as in A. chamissonis, so this plant is now considered to be a variety rather than a distinct species. It grows from Baja California to British Columbia, and is almost continuously present on sandy beaches throughout this range. It is not limited to the open coast, either; there are robust stands of it in Puget Sound, the San Juan Archipelago, and other somewhat protected areas.

Dune Tansy
Fernlike leaves and a strong aroma of camphor characterize the dune tansy, Tanacetum camphoratum, and yellow flowers concentrated in buttonlike heads about 1.5 centimeters across. There are no ray flowers. On new growth, the stems and foliage are woolly, sometimes almost white--because they are covered with long, cobwebby hairs. Many of the hairs are shed as the shoots mature. This plant forms clumps up to about 50 or 60 centimeters high. Its range is limited to the region around San Francisco. Farther north, from Humboldt County to British Columbia, there is T. douglasii, the northern dune tansy. It is similar to T. camphoratum, but it has distinct ray flowers, and its foliage is not so woolly.

Marsh Jaumea
Marsh Jaumea (Jaumea carnosa) is characteristically mixed with Salicornia, but only at levels where it is not likely to be covered by the tide. This plant has a fleshy consistency similar to that of Salicornia. The leaves, opposite and nearly cylindrical, are about two to four centimeters long. The flower heads, about one centimeter across, have yellow rays of inconsistent length.

Gumplant
Gumplant, Grindelia integrifolia, is a member of the aster family. It is essentially a small shrub, although little of it is really woody. Its yellow flower heads, resembling those of sunflowers, are up to about four centimeters across, and are produced in great profusion. The toothed, more or less oval leaves clasp the stems. Both the foliage and the curved bracts that surround the bases of the flower heads are resinous. The taxonomy of grindelias has been kicked around a great deal ever since the first few species were described. The plants called G. humilis and G. stricta in books dealing with the flora of California seem to be very similar to G. integrifolia of the Northwest. All three occur around salt marshes and on coastal bluffs.

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Hardstem Bulrush (Family: Cyperaceae)

The hardstem bulrush, Scirpus acutus, is basically a freshwater plant, but it is mentioned here because it is commonly present in shallow ponds and seeps that border salt marshes. The usual height is about 1.5 or 2 meters, but in some populations the height may reach 3 meters. All of the tall portions are flowering stems, the ensheathing leaves being short and partly covered by mud and water. The largest of the few bracts that originate beneath a flower cluster is sharp-tipped and points straight up as if it were an extension of the stem. Scirpus acutus is found in much of North America, and certainly throughout the region covered.

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Goosefoot (Family: Chenopodiaceae)

Pickleweed
The most characteristic flowering plant in salt marshes is the pickleweed or saltwort, Salicornia virginica. This is a member of the goosefoot family, Chenopodiaceae, which has many representatives in saline situations, inland as well as along the coast. Pickleweed forms spreading mats and reaches a height of about 25 centimeters. Its stems are jointed and its leaves are reduced to little scales. The flowers are organized into club-like spikes at the tips of the branches. This species is a perennial, but it is inclined to die back during the winter. Smaller bays, especially those with a fairly steep profile at the shore, may lack Salicornia, or may have just a narrow strip of it in the zone of transition between the marine and terrestrial environments.

Salicornia europaea is an annual species of pickleweed, about 15 cm high. It generally grows in crowded colonies among plants of S. virginica, and is often reddish throughout.

Pickleweed (Salicornia virginica) Photo Credit: NOAA National Estuarine Research Reserve Collection

Saltbush
Saltbush, Atriplex patula, has many varieties spread over North America and parts of the Old World. Certain of them, particularly the variety hastata, are characteristic of drier portions of coastal salt marshes. The younger stems and foliage of A. patula have a mealy look, owing to the scaly outgrowths that cover them. These usually fall away after a while. The outlines of the leaves resemble those of arrowheads, but they are extremely variable. The pistillate flowers are generally in the same spike as the staminate flowers, but below them. The two types of flowers are rarely on separate plants. In any case, the flowers are small, and the pistillate ones are sandwiched between pairs of bracts that resemble the leaves. Atriplex patula is an annual and grows to a height of about 50 centimeters.

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Salt Marsh Dodder (Family: Cuscutaceae)

Wherever S. virginica grows, it is likely to be parasitized by the salt marsh dodder, Cuscuta salina. This is an aberrant member of the family Cuscutaceae, to which morning glories and sweet potatoes belong. Its wire-like stems, orange or yellow in color, wind around pickleweed and are attached to it by connections that penetrate the tissue. The leaves of dodder are so much reduced as to be nearly non­existent, and the plant has no roots and no chlorophyll of its own. Its life as an independent plant is limited to a very short period after the seed germinates. Its small flowers do not look much like those of morning glories, but have basically the same structure.

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Arrowgrass (Family: Juncaginaceae)

Arrowgrass, Triglochin maritimum, belongs to a related family, Juncaginaceae. Its distinctive flowering stems, frequently more than 50 centimeters tall, tower above the other vegetation. The slender, fleshy leaves are concentrated in a basal rosette. Triglochin concinnum, represented in northern Puget Sound's coastal areas by the variety concinnum, is similar, but its flowering spikes are rarely more than 30 centimeters tall. Its leaf blades are only about one millimeter wide, whereas those of T. maritimum are commonly three to five millimeters wide.

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Sea Thrift (Family: Plumbaginaceae)

Sea Thrift, Armeria maritima, is the only member of the leadwort family (Plumbaginaceae) found north of the Oregon-California border. It forms evergreen tufts in which there are many slender basal leaves, and its small rose-pink flowers are concentrated in dense heads lifted 10 to 30 centimeters above the ground. When in bloom, on seaside bluffs and among rocks covered by Caloplaca and other lichens, it is a lovely sight. Unfortunately, it is not of general occurrence in the Puget Sound region. In the San Juan Archipelago, for instance, it is more likely to be seen on some of the smaller islands than on the major islands. The same species of Armeria is found on the Atlantic coast of North America and in Europe. In England, it has served as a symbol of thrift and has even been featured on postage stamps.

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Eelgrass & Surfgrass (Family: Zosteraceae)

The surfgrass, Phyllospadix scouleri, is not a true grass, but it does have flowers, and the family to which it belongs (Zosteraceae) is not far from the grasses. Its bright green leaves are narrow (generally under 3 millimeters wide) and usually about 30 to 50 centimeters long. They arise from short stalks produced by a fuzzy, creeping stem. The flowers are borne in tight, caterpillar-like clusters, and pollination takes place under water.

A narrow-leaved form of eelgrass, Zostera marina, is occasionally found in pools and channels on rocky shores, especially where there is relatively little wave action. It can easily be confused with Phyllospadix. The two genera may be positively distinguished during the summer by the arrangement of their flowers. In Phyllospadix, the pollen-bearing ("male") flowers and the flowers that ultimately produce seed ("female") are not only in separate clusters, but on separate plants. In Zostera, both types of flowers occur in the same cluster.

Eelgrass (Zostera marina) Photo Credit: NOAA

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References Cited

1. Flora, Charles, and Eugene Fairbanks. 1977. The Sound and the Sea. Washington State Department of Printing. Olympia, WA.

2. Kozloff, Eugene N. 1973. Seashore Life of the Northern Pacific Coast. University of Washington Press. Seattle, WA.