(12) Larkspurs: For low larkspur--ester of 2,4-D at 3 pounds; for tall 

 larkspur--ester of 2,4-D at 6 pounds. Repeated annual applications at the 

 prebud stage of growth may be necessary. 



Comments and precautions : Single applications of foliage sprays will 

 often control mesquite, sand sage, and big sagebrush. Repeated treat- 

 ments, however, are frequently needed. For satisfactory control of 

 mixed stands of oak species and buckbrush, repeated annual applica- 

 tions for 2 or more consecutive years are normally required. 



High- Volume Equipment Applications 



(1) Foliage sprays applied with high-volume ground equipment also may 

 be used to control the above species. Depending on the tolerance of the 

 particular species, 2,4-D, 2,4,5-T, or silvex should be applied at 2 to 3 

 pounds in 100 gallons of water per acre. The best time to apply foliage 

 sprays on most woody plants is at the full-leaf stage and during the 3- to 

 4-week period thereafter, providing conditions are favorable for active 

 growth before the time of application. All foliage should be wet com- 

 pletely with this spray. 



(2) Ammonium sulfamate at 3/4 pound in 1 gallon of water applied to 

 foliage as a wetting spray is effective for control of mixed brush. It is less 

 hazardous in areas growing crops sensitive to 2,4-D and 2,4,5-T, but is 

 corrosive to equipment. 



Individual Tree Treatments 



Individual plants of woody species can be killed at any season of the 

 year by the ester of 2,4-D, 2,4,5-T, or silvex in a light oil, such as diesel 

 or kerosene, applied to the basal bark or cut surface of trees. These 

 treatments are particularly appropriate for scattered stands growing either 

 nearby or in the same pasture with legumes or other susceptible pasture 

 or crop plants. (Treatments are fully described in Sec. VII, page 39.) 



Comments and precautions .- -In attempting to control weeds and 

 woody plants growing in association with desirable forage grasses and 

 legumes, it should be remembered that the margin of selectivity is often 

 narrow. The difference between weed and brush control and no injury 

 to forage species or severe injury to forage crops may often depend on 

 a number of conditions that are subject to the fluctuations of environ- 

 ment in localized areas. 



General Considerations 



An attempt always should be made to apply the herbicide when weeds are 

 most susceptible and when desirable species are least likely to be injured. 

 These times of application are not always compatible* Frequently, desirable 

 species are susceptible at the same time weeds are most susceptible. In 

 these instances, the seriousness of weed infestation will influence the 

 decision to use herbicides or not. 



Whenever possible, allow the weed canopy or companion- crop canopy 

 to develop so it will mask the spray from the forage species. 



The herbicides 2,4-D, 2,4,5-T, silvex, and MCPA are not poisonous to 

 livestock at the rates of application used to control weeds in forage crops, 

 pastures, \ and rangelands. If no poisonous plants are present in the treated 

 area, livestock need not be removed during or after application. 



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