Americanized Jointed Goatgrass Gardens Away From Winter Wheat

Summary: Americanized jointed goatgrass gardens have many seeds, wheat aphids, wheat rust and wheat streak mosaic virus that harm fallow grounds and winter wheat.

jointed goatgrass (Aegilops cylindrica), a colonizer of crop fields and roadsides in west central Montana; Cascade, Cascade County, Montana; July 6, 2013: Matt Lavin, CC BY SA 2.0, via Flickr

Americanized jointed goatgrass gardens apply ground cover most effectively to compacted, disturbed, polluted or unbalanced soils away from the Russian native herb's economically significant relatives, including bamboo, corn, rice, sorghum and sugarcane.

The annual or winter annual in the Poaceae family of herbaceous grasses brings in such pathogens and pests as wheat streak mosaic virus and wheat aphids. Richard Dickinson, in Weeds of North America, University of Chicago publication from 2014, calculates jointed goatgrass causing 25 to 32 percent reductions in winter wheat yields. He describes 50,000-acre (20,234.28-hectare) yearly increases to 2.5 million acres (1,011,714.11 hectares) of goatgrass-infested fallow land and 5 million acres (2,023,428.21 hectares) of goatgrass-infested winter wheat.

Alberta and British Columbia provincial, Arizona, California, Colorado, Idaho, New Mexico, Oregon and Washington state and Canadian and Mexican federal legislation exclude jointed goatgrass for weediness.

A membranous, projecting ligule not even 0.02 inches (0.5 millimeters) long fits atop the sheath of the seedling's red- to brown-green embryonic leaf, called a cotyledon.

Mature stages get hairy, 0.79- to 4.72-inch- (2- to 12-centimeter-) long, 0.08- to 0.19-inch- (2- to 5-millimeter-) wide foliage with hairy, overlapping margins on open sheaths. Ligules, under 0.08 inches (2 millimeters) long, have fringed, upper margins and sickle-shaped, 0.02-inch- (0.5-millimeter-) long auricles with 0.04- to 0.12-inch- (1- to 3-millimeter-) long hairs. The foliage is on jointed, 7.87- to 35.43-inch- (20- to 90-centimeter-) tall stems, the first of which includes as many as 135 branch- or stem-like tillers.

Hormones and nutrients from fibrous roots and hormones and photosynthates in tufted stems jumpstart Americanized jointed goatgrass gardens into resource-grabbing maturity in advance of cereal crops.

Branched, cylindrical, May- through July-blooming, 1.97- to 3.94-inch- (5- to 10-centimeter-) long inflorescences called panicles, with five to 10 spikelets attached to stems, keep leaves company.

Each direct leaf-to-stem attachment, called a node, lines up one edgewise-lounging, two- to five-flowered, unbranched, 0.32- to 0.39-inch- (8- to 10-millimeter-) long cluster called a spikelet. Basal, diminutive, leaflike, 0.28- to 0.35-inch- (7- to 9-millimeter-) long glumes and bristly, stiff, 0.35- to 0.71-inch- (9- to 18-millimeter-) long awns mingle on upper spikelets. Five-veined, flower-defending, leaflike, 0.35- to 0.43-inch- (9- to 11-millimeter-) long lemmas and bristly, stiff, 1.58- to 1.97-inch- (4- to 5-centimeter-) long awns nestle into terminal spikelets.

Lemmas with one bristly, stiff, 0.39- to 3.54-inch- (1- to 9-centimeter-) long awn or with sharp points occur on lower spikelets in Americanized jointed goatgrass gardens.

Each mature jointed goatgrass plant optimally produces 100 spikes, 1,500 spikelets and 3,000 oblong, 0.16- to 0.19-inch- (4- to 5-millimeter-) long, pale yellow to green seeds.

The fruit qualifies as a winter wheat-like grain, called a caryopsis, 0.12 inch (3 millimeters) in diameter, with 0.06- to 2.36-inch- (1.5- to 60-millimeter-) long awns. Jointed goatgrass, described by Austrian botanist Nicolaus Thomas Host (Dec. 6, 1761-Jan. 13, 1834) and named Aegilops cylindrica (goat-eye cylindrical), retains three- to five-year, in-soil viabilities. Seeds sprout between 37.4 and 95 degrees Fahrenheit (3 and 35 degrees Celsius) at 1.97-inch (5-centimeter) depths even though low-positioned spikelet seeds stay dormant until spring.

Americanized jointed goatgrass gardens tackle barren, compacted, disturbed, unbalanced soils but terrorize winter wheat landowners by transmitting wheat aphids, wheat rust and wheat streak mosaic virus.

jointed goatgrass (Aegilops cylindrica); East End, Boise, Ada County, southwestern Idaho; June 8, 2007: Matt Lavin, CC BY SA 2.0, via Flickr

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

jointed goatgrass (Aegilops cylindrica), a colonizer of crop fields and roadsides in west central Montana; Cascade, Cascade County, Montana; July 6, 2013: Matt Lavin, CC BY SA 2.0, via Flickr @ https://www.flickr.com/photos/plant_diversity/9579372260/

jointed goatgrass (Aegilops cylindrica); East End, Boise, Ada County, southwestern Idaho; June 8, 2007: Matt Lavin, CC BY SA 2.0, via Flickr @ https://www.flickr.com/photos/plant_diversity/3822187792/

For further information:

"Aegilops cylindrica Host." Tropicos® > Name Search.
Available @ http://www.tropicos.org/Name/25500185

Dickinson, Richard; and Royer, France. 2014. Weeds of North America. Chicago IL; London, England: The University of Chicago Press.

Host, Nicolaus Thomas. 1802. "Aegilops cylindrica." Icones et Descriptiones Graminum Austriacorum, vol. II: 6-7.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/298398

Weakley, Alan S.; Ludwig, J. Christopher; and Townsend, John F. 2012. Flora of Virginia. Edited by Bland Crowder. Fort Worth TX: BRIT Press, Botanical Research Institute of Texas.