See the bee?

Can you find the happy bee, feasting on nectar? (click to view ... maybe)

My header photo is changing soon has changed, so this is a good time to pay tribute to the Rocky Mountain bee-plant, featured during my first year of blogging (old header is at end of post).  Its Latin name is Cleome serrulata, and the common names are many:  Rocky Mountain beeweed, spider-flower, stinking-clover, stinkweed, Navajo spinach and others.  I prefer bee-plant because it clearly is one.  Every summer when the ones in the backyard bloom, they fill with bees.  The buzzing is quite audible.  When I walk through the bee-plant forest, few bees notice.  They keep foraging intently, focussed entirely on nectar.

Given the inadequacy of the display on my point-and-shoot in full sun, all I can do is point and hope that I’ve caught a bee or two.  Fortunately there are so many bees in the bee-plants that my chances of getting at least one are good.

Bee on bee-plant.

Try an easier one:

Here's one of the bees (center left in photo above):

and another -- a bee butt shot:

Rocky Mountain bee-plants are robust tap-rooted annuals that can grow to four feet in height.  The leaves are compound, made up of three leaflets (left).  As some of its common names suggest, the plants are malodorous -- described as horrible, foul, skunky and like over-cooked spinach.  I don’t find the odor that offensive; in any case, it isn’t terribly strong.  It disappears with cooking, and bee-plants were collected and eaten by various American Indian tribes.  "Navajo spinach" is still used by the Navajo, both for food (so I've read, though it requires lots of boiling) and as a source of black dye for pottery.

Pink-and-green is the theme: green leaves and pink flowers, with pink filaments topped by green anthers!

Given enough space and a little rain every now and then, Rocky Mountain bee-plants branch widely, and produce many clusters of magenta-to-pink or sometimes white flowers.  The flowering period is long; my stand of bee-plants blooms almost until the end of the growing season.  Flowers are similar to those of the closely-related Mustard Family, with four sepals, four petals, six stamens and a single pistil.  The stamens are particularly lovely, with long pink filaments and green anthers.  Inside the flower, at the base of the ovary, is a gland that produces abundant nectar.  This is why bees love bee-plants.

Pendant pods develop even as new flowers continue to be produced; each pod contains about 20 seeds.  A healthy bee-plant will yield on the order of 25,000 viable seeds!  Doves are famous for their fondness for bee-plant seeds, but it is sparrows and finches that consume most of the ones in my yard.  They eat them right off the plants -- these large annuals are robust enough for small birds to perch on the branches.

Rocky Mountain bee-plant was formally described by Frederick T. Pursh in 1814, based on three specimens collected by the Lewis and Clark expedition in what is now South Dakota.  It is native to much of western North America and the Great Plains, and has become naturalized further east.

Cleome serrulata, from Pursh's 1814 treatise on the flora of North America.

A bee with a plan ...

The University of Wyoming and the Western Society of Weed Science have officially proclaimed Rocky Mountain bee-plant to be a weed, for the simple reason that livestock won’t eat it (Whitson 1991).  Never mind that it occupies disturbed sites, does not persist as vegetation becomes established, does not invade intact grasslands, and provides high-quality habitat for a wide-range of pollinators.  A land manager that turns to this “definitive work” on weedy plants of the western US will treat Rocky Mountain bee-plant as a weed.  Sad.

A little research would have prevented this error.  Our two species of Cleome (the other is C. lutea, yellow bee-plant or spiderflower) are known to be excellent resources for pollinators.  The diversity of insects that forage on bee-plants is impressive.  Cane (2008) reported that 162 native bee species were found on bee-plants (both species) in Grand Staircase - Escalante National Monument in southern Utah.  Most were generalists that visit a wide range of native and agricultural plant species.  Two important managed agricultural pollinators also utilize bee-plants when available -- alfalfa leaf-cutting bees and honey bees.

... oh boy! treats ahead!!

Bee-plants also are recognized for their ability to colonize disturbed sites, and have been recommended for reclamation seed mixes as well as for rehabilitation of western rangelands (Cane 2008).  The plants grow well with very little care or water, and produce large quantities of viable nutritious seed.

Last year, Ralph demolished a flower bed in the interest of a new sewer line.

This year, the bee-plants are back, all on their own.

Information Sources

Cane, J.H.  2008.  Breeding biologies, seed production and species-rich bee guilds of Cleome lutea and Cleome serrulata (Cleomaceae).  Plant Species Biology 23: 152-158.

Pursh, F.T.  1814.  Flora Americae Septentrionalis or, A systematic arrangement and description of the plants of North America.  Vol. 2.  London:  White, Cochrance, and co.  Available at: http://www.botanicus.org/item/31753000141777

Tucker and Vanderpool moved the Rocky Mountain bee-plant to the genus Peritoma in the Flora of North America.  See http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=10199 for more exciting details :-j

The USDA Forest Service featured the Rocky Mountain bee-plant as Plant of the Week.

Whitson, T.D. 1991.  Weeds of the west: Western Society of Weed Science in cooperation with the Western United States Land Grant Universities Cooperative Extension Services.  Laramie:  University of Wyoming.