CONCLUSIONS 

 Evaluation of effects of combinations of GA 3 and 2,4-D on 

 waterhyacinths in this study indicate that 



1. Under field conditions existing during this study, there was no 

 significant synergism between 2,4-D and GA 3 in terms of increased effi- 

 cacy of 2,4-D. At best, the response of waterhyacinths to combinations 

 of GA 3 and 2,4-D was additive. However, the use of these compounds 

 under other conditions may yield differing results. 



2. Pretreatment of waterhyacinths with 100 mg/1 GA 3 does not signi- 

 ficantly increase the translocation of C labeled 2,4-D to meristematic 

 waterhyacinth tissues on either a dpm/mg or percent of total C 

 translocated basis. The data suggest a possible increase in transloca- 

 tion to leaves other than the leaf receiving direct 2,4-D treatment. 



3. Costs analysis of utilizing GA 3 in conjunction with 2,4-D in 

 order to lower rates of 2,4-D used to control waterhyacinths on an 

 operational basis indicated that the addition of GA 3 was not economi- 

 cally justified. However, the use of these compounds under differing 

 field conditions and/or a significant change in the cost of 2,4-D or 

 GA 3 may alter this situation. 



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