Railroads, as is well known, are very efficient agents in aiding 
the distribution of plants ; trains, and especially freight trains, pass¬ 
ing through a district where any particular plant abounds afford 
convenient lodging places, on the trucks, or among the cargo of open 
cars, for plants, or parts of plants, or seeds, which are thus trans¬ 
ported long distances. The bedding used in stock-cars may abound 
in weed seeds; it may be carried back and forth, to be finally 
thrown out at some point far removed from the point of shipment 
New plants, strangers in the locality, make their appearance, they 
multiply and spread, or die out, according as the conditions are 
favorable or unfavorable to their growth. It is probable that 
several localities reporting the presence of the Russian thistle owe 
its introduction to the agency above mentioned. 
The Russian thistle is in itself a good traveler, being one of 
the most perfect tumble-weeds known, but it is not probable that it 
came to us unassisted, because of the distance from previously in¬ 
fected sections, and the fact that there are intermediate areas from 
which the plant has not been reported. From the information now 
at hand, it appears that seventeen counties in Colorado are infested 
with the plant in greater or less degree; these are Weld, Logan, 
Phillips, Yuma, Washington, Morgan, Boulder, Jefferson, Arapahoe, 
Elbert, Lincoln, Kit Carson, Fremont, Pueblo, Otero, Bent, and 
Prowers. It is very probable that it exists in four other counties, 
namely: Larimer, Sedgwick, Cheyenne, and Kiowa, but we have 
as yet no information to confirm this suspicion. 
The counties known to be infested are all agricultural counties, 
and a glance at the list will at once show what a wide distribution 
the plant already has; it is so widely distributed and has obtained 
so strong a foothold that it is a serious menace to our agricultural 
interests. The presence of the plant in Weld County was brought 
to our notice in a letter from Hon. J. S. Newell, ot the Board of 
County Commissioners. We visited LaSalle, the locality indicated, 
and traveled over the infested area ; from inquiries made it appears 
that the plant was first noticed in the fall of 1892, near the Union 
Pacific tracks; no one who saw it knew what it was and no atten¬ 
tion was given to it. In 1893 it appeared in quantity along the 
bank of the canal, and many plants were seen in adjoining fields. 
This present season it spread still further ; the canal bank was 
occupied for a half mile east from the point of infection , the lateial 
ditches were lined with it, affording a striking illustration of the 
efficacv of the irrigating ditch as an agency in the dissemination of 
weed seeds; an area of waste land adjoining the main canal was 
covered with the plant, and numerous specimens weie seen in 
neighboring fields of potatoes and corn. 
Mr. Newell had previously visited this locality, and I found 
the farmers advised as to the nature of the plant. A knowledge 
