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THE MONTHLY BULLETIN. 



Weeds in Modoc consist chiefly of the common garden sorts such as wild mustard, 

 pigweed, etc. Russian thistle has appeared in one locality only, covering an area 

 of probably 1G0 acres. Canada thistle and morning-glory, in small patches, are 

 more common. Generally speaking, however, noxious weeds are few and as large 

 areas in this county are used for grazing I am going to use every precaution possible 

 by cooperating with the range riders and the forest service to prevent the introduc- 

 tion of yellow star thistle and other weeds so detrimental to stock grazing. 



The reader will understand that my work in Modoc County may differ very 

 materially from that of horticultural commissioners in other counties, owing to the 

 fact that it is much more common to see a herd of sheep or cattle numbering 500 

 to 5,000 head, than it is to see an orchard with a like number of fruit trees. The 

 reason I mention this fact is to show the importance and absolute necessity to be 

 up and in arms against the introduction of any foreign weed detrimental to the 

 welfare of our principal industry, stock raising. 



THE RUSSIAN THISTLE (Salsola kali: variety tragus), 

 ITS CONTROL AND ERADICATION. 



By J. B. Hickman, County Horticultural Commissioner, Aromas, Cat. 



The Russian thistle is an annual having a central stalk with a taproot, from 

 which the mature plant breaks away and, blown along over the ground, scatters 

 seed broadcast. It is a dry-land plant, the seed germinating under light moisture. 



The young plants are green and tender in appear- 

 ance — a food in this stage, relished by all stock and 

 easily eradicated. The mature plants are rigid, 

 spinous, dense and unapproachable; impossible to 

 cut off by any ordinary implement where grown 

 large under favorable conditions, as no hoe, grub ax 

 or other like tool can reach the central stalk protected 

 by the curving spinous branches. 



Control of this weed pest as a preliminary step 

 to its eradication seems to imply the prevention of 

 its spread over new territory and necessitates the 

 destruction of all plants prior to blooming and 

 before they become large enough to be blown about 

 by winds, as well as the prevention of infestation of 

 hay or grain by mature specimens. 



As barley is cut before the Russian thistle matures 

 we need not expect to find it infested, but a ship- 

 ment of wheat for chicken feed from a neighboring 

 county had numerous fragments of mature Russian 

 thistle plants in every sack, proving conclusively that 

 Russian thistle ripens with wheat. In grain hay 

 the danger lies in the plants that are caught by the buckrake when carrying 

 seasoned hay shocks to the baler. While seeds of Russian thistle are so sensitive 

 to excess of moisture that they rarely sprout or thrive in alfalfa checks, they do 

 thrive on the levees, and by the time the third or fourth cutting is ready may have 

 mature seed, be baled with the hay and so carry the infestation indefinitely. 

 Monterey County, without doubt received most, if not all, of its early infestation 

 through infested alfalfa seed. Its appearance was first noticed in at least three 

 instances in newly-planted alfalfa. 



The seeds retain their vitality but two years at best, and when crowded or shaded 

 by other plants, even if it be warm enough to germinate the seeds, the seedlings 

 smother before maturing. 



Aside from natural and usual transportation avenues for spreading its seeds, 

 muddy wagon wheels driven through infested areas will sometimes do considerable 

 barm. In one case in this county, this was the cause of a double row of neatly 

 drilled in Russian thistle in a warm sandblow the following summer. Incidentally 

 such wagon wheels traversing highways plant seeds at widely distant points and 

 such new infestations make necessary the utmost watchfulness and solicitude on 

 the part of inspectors. 



