Sandberg Bluegrass

Why talk about grasses when there are so many other beautiful wildflowers, spectacular trees, grotesque fungi and other fauna and flora that outshine the unassuming grasses? If one takes the time to study and observe grasses, their natural history and variety are as interesting, in an understated manner, as any orchid. Leonard’s particular interest is grasses and through him I have learned to appreciate, and observe, these humble plants.

Sandberg bluegrass was collected and described in 1892 by John Herman Sandberg, a Swedish botanist, who cataloged the plants of the Pacific Northwest while working for the Department of Agriculture between 1886 and 1893. As others studied the literature and studied collected plant specimens, it became obvious that as many as 45 “different” species described the same grass as Sandberg – including one from the Lewis and Clark Expedition. As a result there were many scientific and common names associated with the same plant. Poa secunda is the currently accepted scientific name for the grass Sandberg collected in 1892. It is a highly variable species with many identified subspecies and a plethora of colloquial names including alkali bluegrass, Canby’s bluegrass, one-sided bluegrass, and Nevada bluegrass.

Sandberg bluegrass is a perennial native to and found from North Dakota to the Yukon Territory and south to Nebraska, New Mexico and Southern California. It is also native to Argentina and is found in Chile. (I would like an explanation for the South American populations.) Several commercial cultivars of Sandberg bluegrass have been developed for revegetation and soil conservation so the plant is spreading into other states beyond its native range.

Growing in plains, in dry woods and on rocky slopes at mid to high elevations, Sandberg bluegrass does well in alkaline and saline soils as well as rich, well-drained soils. In areas where there is periodic flooding or lingering wet conditions, this grass does not grow, but it is highly resistant to drought. It requires full sunlight or partial shade and can be “shaded out” by thick, tall stands of sagebrush.

Sandberg bluegrass is a cool-season bunchgrass that is relatively short-lived. It grows as a dense tuft of short basal foliage. There are usually one or two taller flowering stems per plant. It has narrow leaf blades and no hairs on the surface of the leaf sheath. The inflorescence can have over 100 spikelets (the floral unit of a grass inflorescence). The spikelets are often tinged purple. The glumes (bracts at the base of a spikelet) have no awns (bristle-shaped appendage). The root system has penetrating deep roots and an extensive network of shallow roots. The plants are pollinated by wind or are self-fertile. Sandberg bluegrass can also produce viable seeds without pollination through an asexual system called facultative apomixis.

Sandberg bluegrass matures early and provides fodder for livestock and wild animals in the spring before other grasses begin to green. During the summer animals will eat some Sandberg bluegrass but prefer the later maturing grass species. The cured Sandberg bluegrass vegetation is grazed in the fall. More importantly, Sandberg bluegrass revives with fall rains, even the lightest precipitation, and continues to grow into the winter. Since it provides both an early source of protein in the spring and a fall/early winter source of protein, Sandberg bluegrass is an important forage. Sandberg bluegrass continues to thrive with heavy grazing pressure and after fire making it additionally valuable as forage.

Dead Poa secunda clumps provide habitat for woven-spore lichen, a rare species found in Oregon and Washington. This lichen depends on dead organic matter for a substrate and is found almost exclusively on Sandberg bluegrass detritus.

These Sandberg bluegrass specimens were photographed in May along California Highway 139 between Eagle Lake and the Termo Turnoff (Lassen County).




Gallery | This entry was posted in Grasses and tagged , , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s