Sunday, June 14, 2015

Hop Clover

Weather: Rain yesterday. Earlier in week, clouds came up so the highest temperatures were around noon.

For the first time in years, there are no restrictions on the local ditch, except, of course, paying your dues. They even are running some at night for anyone with "large acreage."

What’s blooming in the area: Dr Huey, pink, and hybrid tea roses, catalpa, silver lace vine, datura, red hot poker, sweet pea, alfalfa, purple salvia, golden spur columbine, pink evening primrose, blue flax, Jupiter’s beard, Queen Anne’s lace, Shasta daisy, coreopsis, brome grass.

Beyond the walls and fences: Apache plume, tamarix, alfilerillo, tumble mustard, oxalis, bindweed, scurf pea, loco, goat’s head, goat’s beard, plains paper flower, green-leaf five-eyes, flea bane, common and local dandelions, June, needle, rice, and cheat grasses.

In my yard: Rugosa roses, potentilla, chives, vinca, Saint John’s wort, California poppy, snow-in-summer, Bath pinks, Johnson’s Blue geranium, coral bells, Dutch clover, winecup mallow, Maltese cross, pink and blue salvias, catmints, blanket flower, chocolate flower, anthemis, bachelor button, white yarrow. Reseeded larkspur flowers so far are all dark purple.

Bedding plants: Sweet alyssum, pansy, snapdragon, moss roses, marigold, gazania.

What’s blooming inside: Zonal geraniums, aptenia.

Animal sightings: Hummingbird and other small birds, geckos, bees, ants.

Weekly update: When the new post office was built, someone decided to xeriscape the grounds. Apache plumes and broad-leafed yuccas were planted in gravel mulch near the building.

Whoever made that landscaping decision didn’t realize the gravel would act as nursery for all the weeds blowing off the beds of pick-ups that back into spaces. Periodically a crew is paid to weed eat nature’s volunteers.

The most unusual blooming at the moment is hop clover. I noticed a few plants a year ago. They’ve spread into a dark-green patch of dense, trefoil leaves near the building where the taproots dig into the runoff and afternoon shade protects them. The trimmer’s spinning string throws seed pods a foot away where they plant themselves. Since the annual has a long blooming period, it probably always has seeds at the right stage.

Trifolium campestre has withstood more than a little trimming in its life. Its genus probably emerged around the Mediterranean during the Miocene era of grasses and huge mammals 16 to 23 million years ago. Nick Ellison’s team found this species was unusual among the clovers for being a hybrid. Nigel Maxted and Sarita Jane Bennett believe that plasticity meant it was able to evolve rapidly.

The bright yellow flower is unusual among Trifoliums, which range from white to pink and purple. But there’s no mistaking the flower form: its round head is only smaller and tighter than other clovers. The banner petals remain after they’ve turned brown and surround the single-seeded pods. They catch the wind to disperse the seeds.

The legume spread through the Iberian, Italian, and Balkan peninsulas to the adjacent parts of the near east and to Algeria and Morocco in north Africa. It remained a low growing ground cover spreading on limey soils until the English civil war, when Samuel Hartlib and Richard Weston began promoting improved pastures.

Until then, Caroline Lane says animals were essentially scavengers. "Where there was both arable and livestock rearing, livestock feeding was merely an adjunct to the arable, so that stock was fed upon the stubble of arable crops and whatever land could be grazed."

Hartlib was the grandson of an English merchant in Danzig, who fled from advancing Swedish armies in 1628. He flourished under Oliver Cromwell. The other left for Flanders where he observed local farming techniques. Hartlib published Weston’s letter to his son in 1645 as a Discourse on the Husbandry of Brabant and Flanders. In it, Weston recommended rotating crops and planting clover to improve the land. He also was demonstrating the utility of irrigating hay crops.

The price of meat was increasing with the growth of cities. The demand meant more animals needed to be grown on the same amount of land. That could only be done by improving what they ate. The larger market financed the investments.

It took a while for clover to succeed. Hartlib subsequently published letters from farmers. Some were happy, some had problems. Lane suspects the latter were lacking the soil bacteria the plant needs to convert atmospheric nitrogen into an earthen form. This, of course, is what makes it useful in improving cultivated land.

One problem was getting viable seed. It was adulterated by either Dutch wholesalers or English retailers. To remove seed from the pods, it was dried in a kiln, then threshed. The overdried seeds were exported. In 1675, Richard Haynes patented an invention that would sever, divide, and make seed clean. Weed eaters may serve the same function.

By 1700, Lane says, farmers were planting various types of clovers. It took longer for hop clover to migrate to this country. Edward Voss says it didn’t begin escaping in Michigan until the 1870s into wetlands and moraines. My guess is those areas were raising sheep after the local market for wheat collapsed with the opening of Minnesota lands. The more agricultural parts of the state were growing Dutch clover.

Hop clover rarely appears in New Mexico. It’s a temperate grassland plant that eschews both the arid plains and the very wet southeast. But one thing about the trucks parked at the post office, is, they’ve been everywhere.

Ellison, Nick W., Aaron Liston, JeVrey J. Steiner, Warren M. Williams, Norman L. Taylor, Molecular Phylogenetics of the Clover Genus (Trifolium-Leguminosae)," Molecular Phylogenetics and Evolution 39:688-705:2006.

Lane, Carolina. "The Development of Pastures and Meadows during the Sixteenth and Seventeenth Centuries," The Agricultural History Review 28:8-30:1980.

Maxted, Nigel and Sarita Jane Bennett. "Legume Diversity in the Mediterranean Basin," in Maxted and Bennet, Plant Genetic Resources of Legumes in the Mediterranean, 2001.

Voss, Edward G. Michigan Flora, volume 2, 1985.

Photographs: All taken outside the local post office.
1. Flowers and trefoil leaves, 8 June 2015.
2. Patch from above, 3 April 2015.
3. Close-up of flower, 3 April 2015.
4. Patch in the gravel, 8 June 2015.

1 comment:

Vicki said...

Very interesting history on the Hop Clover. Thanks for posting. I don't believe I've ever seen it growing here, but I'll keep my eyes open.