FIG-. 11. These three specimens of sweet clover show the influence of two mineral 

 deficiencies, phosphorus and potassium. All three received ample lime, but lime 

 (calcium) alone is not enough. The two specimens on the left are sick with 

 root rot; they were easily pulled from the ground by hand. The healthy roots 

 on the right could not be pulled from the earth. 



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