320 OHIO EXPERIMENT STATION: BULLETIN 175. 



97 Western Orache (A) * A triplex tmncaia (Torr. ) A. Gray. This 

 requires notice here, since the flat triangular fruits, containing- small, circular 

 seeds, are often found in alfalfa seed. For these, see seed cuts. 



98 Russian Thistle, Russian Tumbleweed (A) *Salsola Tragus^. This 

 plant, which is properly a tumbleweed, not a thistle, early proved very aggress- 

 ive in the west. It was introduced into what is now South Dakota in flax seed a 

 little more than twenty-five years ago. Its occurrence in Ohio has thus far been 

 limited to points along trunk railways, and occasional fields where it seems to 

 have been scattered from western stock cars or in seeds. It has been found in 

 ten or more counties, beginning to appear in 1893. The plant varies greatly in 

 appearance and in leaf character at different stages of growth. While the 

 plants are young the leaves are long and slender, two inches or more in length 

 and less than one-eighth inch in width, but when older these slender leaves 

 drop off to give place to triple, half-inch spines on the flowering branches. At 

 this stage the plant often becomes very large and spreading, forming a top 

 about two feet in height and from two to six feet in diameter. The leaves on 

 this plant are never much wider than wooden tooth-picks and form no broad 

 leaf blade. This alone will enable an observer to distinguish it from the 

 common tumbleweed which is so frequently mistaken for it. On the tumble- 

 weed there are flat leaves about two inches long having a broadened blade 

 1-2 inch or more in width. The Russian thistle has, so far as now known, 

 been exterminated at every point where it has been introduced in Ohio, thanks 

 to the interest taken by the railway officials and others. The attention given 

 the Russian thistle has led to greater care generally in the destruction of 

 weeds along railroad rights-of-wiy. While a great deal more yet remains to 

 be secured, it seems to me that this weed affords an illustration of what can be 

 done in limiting the spread of a newly introduced weed. 



The seeds of the Russian thistle are very characteristic, about the size of 

 clover seed, light yellow, conical, showing coiled embryo, but usually invested 

 by a thin, grayish coating. They are very different from those of tumbleweed 

 which are much smaller, flattened, round, dark and shining; they occur fre- 

 quently in alfalfa seed from the west. To eradicate the Russian thistle it is 

 only necessary to uproot all plants before August 15th. After that date it is 

 necessary to burn the plants which are green and succulent, with brush or 

 logs. It has proved passible to prevent this weed from gaining wide dissemina- 

 tion in Ohio. Yet this result was reached through persistent care and by 

 reason of the easier handling of the weed. 



99 Kochia (A) *Kochia Scoparia (L. ) Roth. This plant is now very 

 commonly cultivated aud has freely escaped about Wooster as well as elsewhere 

 in Ohio. Its resemblance to evergreens in form of growth makes it popular as 

 a border plant; the change to reddish color of stems and leaves in autumn is also 

 a noticeable feature. The plant is liable in time to become common as a weed 

 and to have similar characters, as such, to others of the tribe. Seeds less regu- 

 lar than those of lamb's-quarters, 1-20 inch in diameter, dull and dark. 



PIGWEED FAMILY, AMARANTHACEiE. 



100 Tumbleweed (A) *Amaranthus graecizans L. This weed, Fig. 19, is 

 another of the pernicious annuals of which we have by far too many. It com- 

 monly grows about a foot in height and one or two feet in diameter, and is 

 likely to be found in waste grounds generally. It is not very frequent in 

 cultivated lands but is often met with along railways. It may be distinguished 

 from the Russian thistle, for which it is often taken, by its having leaves with 

 a definite, flattened blade 1-2 inch or more in width and by the small, round, 

 shining seeds. It is attacked by a white mold, Cystopus Bliti (Biv.) L£v., which 

 also attacks the beet. 



