HOW TO OET THE LAST TICK. 9 



Time required to free pastures from ticks by starvation. 



This table may also be used as an accurate guide to 

 determine the length of time it is necessary to con- 

 tinue systematic dipping to insure complete eradica- 

 tion. It is evident that if all ticks are prevented by 

 dipping from maturing and reinfesting a pasture, 

 that pasture should be tick-free in the same length 

 of time that it would take to starve out the ticks if all 

 cattle, horses, and mules were excluded. In the appli- 

 cation of this knowledge, where dipping is the means 

 of preventing pasture reinfestation, it is, of course, 

 necessary that careful inspection be made at the time 

 of dipping to determine when mature ticks are last 

 found on the cattle; the time dipping must continue 

 is estimated from that date. In using this plan it 

 has been the policy of the writer, with satisfactory 

 results, as a margin of safety, to add 30 days to the 

 starvation period. For example, mature ticks (not 

 necessarily engorged) are last found on cattle being 

 dipped on June 1 — then those cattle should be 

 dipped regularly at 14-day intervals until November 

 30 ; or if mature ticks are found July 1, the eradication 

 will not be completed until the following April 1. 



Systematic dipping in an arsenical solution is the 

 method most generally followed in tick eradication. 



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