-32- 



Again the attempts at control were quite ineffective. The addition of clay 

 had no observable effect on turbidity in the absence of the chemical, and 

 there was little oi no correlation between weight of carp used and turbidities 

 created. 



The final alignment vfas now six ponds treated with chemical, six with 

 carp, and two left untreated as controls. The six ponds receiving the chemical 

 were first muddied ^iay 11-14, the carp were added on May 18, 1955. Each 

 pond was stocked with 125 largemouth bass, 100 bluegill and 50 channel cat- 

 fish. The bass were young of the year with an average length of 1.9 inches 

 ( range : 1,7 - 2.1). Both the bluegills and the channel catfish were yearling 

 fish - the bluegills averaging 3.1 inches (ranges 1.9 - 4.5), and the channel 

 catfish 3.5 inches (range: 2.7 - 4.2). The bluegills were stocked on April 28, 

 the bass and channel catfish on May 17 and 18. The ponds were revisited once 

 each third week throughout the summer to take plankton and turbidity samples 

 and to check the need for further treatment. Ponds 5, 6, 9 and 10 were given 

 additional treatments on May 25, July 25, and August 25, 1955, to maintain 

 their turbidities, and the water levels of all ponds were raised at these times. 

 Eight of the clearer ponds also developed excessive growths of vegetation 

 (mostly bushy pondweeds, Majas spp. ) , which were twice thinned to prevent the 

 ponds from being overgrown. The ponds were drained during the period October 

 31 to November 2, 1955. 



FINDINGS FROM THE HATCHERY PONDS 



As in the farm ponds, the clear hatchery water produced notably faster 

 growths, as well as greater total weights of bass and bluegill (Table 7). 

 It was found, however, that channel catfish production was greater in the 



