18 A PROTECTED STOCK RANGE IN ARIZONA. 



and snake weeds of New Mexico, Texas, and northern Arizona. 

 Here this plant has spread upward from the river bottom and now 

 occupies the rocky ridges and mesas between the grassy section and 

 the more level desert lands below. It has thickened and increased 

 perceptibly during the last five years. The rainfall in the region where 

 it is most abundant was very, light in 1908, and it consequently 

 made but little growth. No one can tell what the future of this plant 

 may be; it is quite probable that the grasses unmolested would hold 

 their own against its encroachments, but with the grassy vegetation 

 weakened by grazing it may increase to such an extent as to crowd 

 out nearly all of the valuable plants, as is done over thousands of 

 acres in other regions by species of Gutierrezia. 



Remedies which are effective and at the same time economically 

 applied in the control of the variety of rayless golden-rod mentioned 

 have not been perfected as yet. Burning in the dry season in sum- 

 mer will kill some species of the group. In other words, if there is 

 sufficient herbage upon the ground to burn during the vegetative 

 condition of these plants they will be killed by burning the land over, 

 but burning during the winter season, when they are dormant, will 

 not kill them. 



In the region under consideration the golden-rod referred to has 

 increased mainly below the grassy area, such increase having taken 

 place but partially during the time that the area has been under 

 protection. The encroachment evidently had begun years before. 

 It is not yet thick enough to burn, even during the dormant dry 

 season. Should all the young plants in evidence in 1908 come to 

 maturity, which is rather improbable, it would be thick enough to 

 burn in two or three years. The grasses do not become abundant 

 enough here to allow of burning. The weed is increasing in the lower 

 grassy areas, but principally in that region which now, as probably 

 always, is producing mainly annual grasses. How far it will increase 

 in the perennial-grass areas and how its encroachments within and 

 without the fence will compare can not yet be satisfactorily judged. 

 It must be remembered that it takes very much longer to secure 

 positive results in matters of this kind in this region of scanty rain- 

 fall than in more favored localities. There are indications that the 

 plant has about reached the limit of its growth here, as the sheep 

 weeds have elsewhere, and like them has begun to die. In 1909 a 

 large proportion of the plants were dead and none were as vigorous 

 as in previous years, although the season was exceptionally favorable. 



The only other real weed is the loco weed (Lupinus arizoniciis). 

 This is supposed to have done much damage to the horse industry, 

 but does not appear to be as injurious to cattle. So serious is the 

 matter considered that at least one rancher in the vicinity has gone 

 out of the horse business entirely. 



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