
Polygonum pensylvanicum). In the TVA area, these plants will volunteer, so 
seeding is rarely necessary. 
Planting Aquatics 
Effective propagation of aquatic or submergent vegetation for waterfowl in 
the TVA impoundments has been limited to the Guntersville Reservoir. Here water 
fluctuations are restricted, for the most part, to two feet and rarely three feet 
because of the requirements for navigation. Several good duck-food plants — 
mainly longleaf pondweed (Potamogeton americanus), southern pondweed (Po 
diversifolius), watershield (Brasenia schreberi), and southern naiad (Najas 
guadalupensis) -— have been noted growing in this reservoir. The last named, 
southern naiad, though useful to waterfowl, is considered a bad malaria~breeding 
plant and its propagation in TVA is not advisable. Watershield and longleaf 
pondweed have not been condemned by TVA's malaria control officials and, if given 
specific TVA approval, can be planted in areas suitable for their growth. Studies 
conducted in 193 indicate that the longleaf pondweed can be easily introduced 
by live-stem plantings. However, extensive propagation of this species in 
Guntersville Reservoir was hampered by the limited changes in water levels that 
occurred. Concentrated treatment with 2,4-D was also injurious to this pondweed. 
Summary 
Impounding water in the TVA region opened up possibilities for developing 
valuable waterfowl resources. Creating new water bodies, especially fluctuating 
reservoirs, does not in itself necessarily add useful new waterfowl environment. 
It does, however, furnish a physical foundation upon which -~ if opportunities 
permit -- good habitat for birds can be developed. 
Capitalization on such opportunities has necessitated coordination of water- 
fowl management with TVA's multiple activities. Reconciling the development of 
waterfowl habitat with malaria control operations has been a primary problem. 
In some respects, however, the coordination of these seemingly conflicting objec- 
tives has not been as difficult as was anticipated. In some instances, procedures 
satisfactory for both malaria control operations and wildlife management have 
been developed. In connection with malaria control, such operations as water 
level fluctuation, larvicidal treatment, plant control, shoreline conditioning, 
diking and dewatering, require special consideration to avoid serious damage to 
waterfowl values. 
The success of waterfowl habitat development in the TVA area has been 
confirmed by a marked influx of waterfowl. More particularly it has been demon- 
strated by the large numbers of birds present in improved areas as contrasted to 
their scarcity elsewhere. The following are methods of habitat improvement that 
were found especially effective in increasing waterfowl in the TVA region. 
1. Constructing and managing sub-impoundments to develop either stable marsh 
and aquatic habitats or seasonally dewatered units in which agricultural crops 
are raised and subsequently flooded. 
2. Producing unflooded agricultural crops to attract mallards, black ducks, 
and Canada geese. 
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