RED CLOVER -I960 



80 



70 



SO- 



SO 



40 



30 - 



20 



10 





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NEW TIRES 



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CONTROL 500 1100 1500 



DRAWBAR PULL IN 



Figure 6. Effect of increasing drawbar 

 new tires on vieids of red clo 



CONTROL 650 1250 1800 

 POUNDS 



pull with smooth tires and 

 ver (1960). 



drive wheel slippage did not result in a significant decrease 

 in yield over that already inflicted by the effect of tractor 

 weight alone. 



Figure 4 shows the effect of traffic on red clover. Significant 

 damage was inflicted hy smooth tires, the degree of damage 

 increasing as the drawliar load increased. With new tires, how- 

 ever, although some damage was inflicted, the degree of dam- 

 age was not as pronounced as it was with old tires. This sug- 

 gests that the greater area of contact with the smooth tires 

 was a factor. 



