30 



AQUATIC PLANTS IN POND CULTURE. 



The claim of superiority of a raft over the boat ordinarily used 

 for the same purpose seems well founded and leads to the suggestion 

 that a shallow scow of dimensions to suit conditions, with deck and 

 side rails, would also allow the water to drain off as the deck is loaded 

 with vegetation and would be more easily handled. Rapid movement 

 in the comparatively small ponds of the fish culturist not being 

 essential, trucks might be attached to the bottom of the scow for con- 

 venience in drawing it ashore or from one pond to another. 



Fig. 31. — Raft in use at Mammoth Spring, Xrk., station for carrying the loosened vegeta- 

 tion to shore. For description see text. 



At the San Marcos station the removal of aquatic vegetation is 

 accomplished with an ordinary scythe, the men going into the water 

 and cutting the growth as closely as possible. For cutting the heavier 

 vegetation at a distance from the embankments a scythe is sometimes 

 attached to a piece of three-quarter-inch iron piping from 10 to 30 

 feet in length, the latter being spread at the end to hold the shank of 

 the scythe, which is riveted to it with two small bolts. Hand rakes, 

 especially made from 4-tined hayforks, are then used, care being 

 taken to examine each rakeful of foliage for young fish. An especi- 

 ally made iron rake shown in the accompanying illustration has also 



Fig. 32. — Iron rake in use at San Marcos, Tex., station. For description see text. 



proved a very effective implement. The main bar, 3 inches in diame- 

 ter and 8 feet long, is set with 15 teeth 15 inches long, and forms the 

 diagonal of a square frame, at the two remaining corners of which is 

 fixed an iron ring. AVith a strong rope through each ring, the rake 

 is drawn from one side of the pond to the other, making an 8- foot 

 swath. Two men are usually required on each side of the pond to 

 manipulate the rake. 



At the Cold Springs (Ga.) station there is but one pond in which 

 vegetation {Myriophylliim) is sufficiently dense to necessitate its 

 removal j)rior to seining for the young fish. In this pond it grows 



