s 
BULLETIN 309, U. S. DEPARTMENT OF AGEICULTURE. 
summer, for my brother says that all through the present summer it has been cold 
enough for an overcoat at night in the town of Sayula, where he resides. During 
January, he says that it reaches to near zero and at 10 o'clock the next davit is up to 
70° again. 
Mr. O. F. Cook corroborates Mr. McE wen's observations regarding 
the relative coolness of the climate in which this grass thrives. In 
Guatemala, where the former has noted the plant especially, he found 
the same conditions. 
Figure S shows a comparatively sparse stand of zacaton on the 
Vulcan de Agua, near Antigua, Guatemala, one of the early localities 
from which the plant was collected. 
Figure 9, from a photograph taken in Guatemala, shows the grass 
promptly claiming the neglected portion of a formerly cultivated 
field on a terraced hillside along the road between Totonicapam and 
made under the direction of Mr. Cook by Mr. C. B. Doyle, of the 
Bureau of Plant Industry. 
The grass is said to flower from August to October, depending upon 
altitude and other conditions, and usually attains a height of 5 to 7 
feet. The usable portions of the roots vary in length from 2 to 30 
inches. The diameter of the roots range from one sixty-fourth to 
three thirty-seconds of an inch. ' They are gathered at all seasons of 
the year, peons digging them up with an implement resembling a hoe 
in shape. After washing, cleaning, and drying, the roots are cut 
from the grass, graded, and separated according to quality, length, 
and color, and finally baled ready for shipment. Vera Cruz and 
Tampico are the chief exporting ports, while France, German}', and 
the United States are the chief users of the brushes into which the 
roots are manufactured. Roots of a pale yellow, a decidedly charac- 
teristic color, are preferred by the trade. It is estimated that an 
acre of grass yields a ton of marketable roots and at least 3 tons of 
tops. At present the tops are not used in any way. It seems likely 
that root operators might find it worth while to attempt the utilization 
Fig. 6. — Cross section of a leaf blade, x 240, showing hypodermal stereome, 
the large water-storage tissue, the palisade tissue, and the mestome sur- 
rounded by a parenchyma sheath and a thick-walled mestome sheath. 
Quez alt enango, 
Guatemala, show- 
ing also in the 
middle distance, 
on the mountain 
slope below the 
pines, a character- 
istic wire-grass 
formation con- 
tending with the 
pines for suprem- 
acy. Both of 
these figures are 
from negatives 
