AQUATIC PLANTS IN POND CULTURE. 



13 



WTTHEVILLE, VA. 



Here the pond bottoms consist of a rich loam to a depth of 12 

 inches, and the range in water temperature during the summer 

 months is from 70 to 85° F. The following list of plants gives the 

 opinion of a former superintendent as to their respective qualities 

 and characteristics. The preceding lists have not included selni- 

 aquatic or border plants, but arrowhead {Sagittaria longirostra) and 

 water plantain (Alisma pkmtago-aquatica) are given an important 

 place among the plants at this station, A more careful investigation 

 may lead to the conclusion that certain semiaquatic plants are equal 

 in value to some of their exuberant companions of the deeper water. 



The curled-leaved pondweed {Potcvmogeton crispios, fig. 5) is con- 

 sidered the most desirable plant at this station. Its roots are on 



Fig. 23. — Long-beakpd arrowhead (Sa- 

 gittaria loiiffirofiPra). Found in 

 swamps and along- ponds. New Jersey 

 and Pennsylvania to Alaljoma. (After 

 Britton & Brown.) 



Fir. 24. — Water plantain (AU.sma plan- 

 tago-aquatica). Found in .shallow 

 water or mud throughout North Amer- 

 ica, Also in Europe and Asia. (After 

 Britton & Brown.) 



muck bottom in water up to 6 feet deep, and it throws up a slender 

 stalk about 2 inches above the surface, on the tip of which is a small 

 white blossom. The plant grows luxuriantly both in summer and 

 winter and flourishes in both cold and warm water ponds. It fur- 

 nishes abundant shade and protection and is a good breeding place 

 for aquatic insects. It is also easy to control and can be removed 

 from the ponds without injury to the fish. Its only objectionable 

 character is that where the soil is fertile it grows more luxuriantly 

 than is desirable. 



The water weed {Philotria canadensis, fig. 9) exhibits the same 

 characters here as at the Fish Lakes station, but is more highly 

 esteemed, being given second place. 



The parrot-feather {Myi^iophyllum proserpinacoides, fig. 2), root- 

 ing in muck bottom in water up to 6 feet deep, reaches to the sur- 

 face and throws up a slender stalk about 2 inches above, with a small 

 white blossom at the tip. Because of its value as a shade for fish 



