44 



CIRCULAR 491. U. S. DEPARTMENT OF AGRICULTURE 



cult to eradicate by grubbing because its spreading rootstalks are 

 capable of producing new plants at each node, according to Har- 

 vey (34). 



Smith (65, pp. 16-17) reported in 1899: 



Fire is the only remedy which is always effective in fighting the prickly 

 pear, but to develop enough grass and undergrowth so that a fire will run 

 through thickets composed of this cactus requires that cattle shall be kept 

 out of the pastures one and often two years, and few stockmen are willing to 

 sacrifice two years' growth of grass even to rid themselves of the prickly pear. 

 * * * * To be the most effective the pasture should be burned in 'spring 

 just after the new growth has commenced, because the cactus is then most 

 easily destroyed. The young and tender shoots would be scorched and cooked 

 and prevented from further development, and the singeing off of the spines 

 on the older shoots would expose them to destruction by animals. The fire 

 woidd also check the development of the weeds and brush that thrive in the 

 shelter of the clumps of cactus. If hogs or goats could be herded on the 

 prickly pear after the fire, the destruction would be much more complete. 



Figure 22. — Pasture infested with pricklypear (western 



Woodward. Okla. 



pricklypear ) near 



Firing pastures for the control of cacti may be advisable as a last 

 resort in heavy infestations but is certain to be at least temporarily 

 injurious to the grasses in dry localities. After using goats during 

 the clean-up period following the fire, the grasses should be allowed 

 to recuperate by the reduction or exclusion of livestock for indefinite 

 periods. 



BROOMWEEDS 



Many seriously depleted range pastures on semiheavy to heavy soils 

 of shallow to medium-shallow depths have become heavily infested 

 with annual snakeweed (broomweed) (fig. 23) and broom snakeweed 

 ( turpentine weed) . the perennial broomweed. The vigorous growth of 

 these unpalatable plants offers strong competition to the grasses and 

 often seriously delays their recovery. Several ranchers obtained satis- 

 factory results in 1937 from mowing the annual broomweed before t he- 

 seed matured. Kecovery was noticeably more rapid on mowed than on 



