SPATTERDOCK 41 



Tlie most vulnerable stage of growth has been determined to be 

 the period of maximum blooming and early fruiting. Young seed- 

 lings are easily destroyed by dewatering, but killing mature root- 

 stocks by this means is a slow process, especially if the stems are 

 covered by silt. 



HERBICIDES 



A limited recent testing with ATA in New Jersey at 8 pounds 

 acid equivalent per acre has given fairly encouraging results. 

 Combination treatments with 2,4-D and Ammate have consist- 

 ently yielded over 90% control in Tennessee and Delaware. A 

 2,4-D application at the rate of 6 pounds acid equivalent per acre 

 during the time of heavy blooming and early fruiting was fol- 

 lowed a month or 6 weeks later by spraying with Ammate at 80 

 pounds active per acre. Such combination treatments have been 

 more effective than repeated sprayings with either 2,4-D or 

 Ammate. 



MOWING 



Underwater cutting of spatterdock in about 4 feet of water at 

 Reelfoot Lake showed, among other things, that a first cutting 

 during heavy flowering and early fruiting followed by a cutting 

 of regrowth about a month later gave 80% to 90% control. In 

 shallower water, a third cutting about another month later was 

 necessary for equivalent results. Cuttings made without regard 

 to the vulnerable period are generally ineffective. 



REFERENCES 



1950. Waterfowl Habitat Improvement on Reelfoot Lake. John H. Steenis. Jour. 



Tennessee Acad. Sci., 25 (1). 

 1945. A Progress Report on the Marsh and Aquatic Plant Problem: Reelfoot Lake' 



John H. Steenis and Clarence Cot tarn. Jour. Tennessee Acad. Sci., 20 (1) 



