
islands and peninsulas. Studies at the Wheeler and Kentucky reservoirs have shown 
that vegetation, particularly woody growth, can effectively retard such erosion. 
Here, existing trees and shrubs, where sufficient in density, restrain erosion 
along the old river bank. Plantings of fast-growing species, like black locust 
(Robinia pseudoacacia), mainly on the tops of the banks, and more water-tolerant 
species, chiefly willow, on the lower contours reduce the erosion Process Atkeson 
has pointed out that black locust has excellent soil-holding characteristics in 
its fibrous root system, and the ability to sprout readily from the roots. In 
the TVA lakes, with the exception of the Guntersville Reservoir, there 1s too much 
change of water level to allow effective retarding of erosion by perennial marsh 
vegetation, such as bulrushes, except when in conjunction with woody plants men- 
tioned above. 
Improving Islands and Mud Flats 
Three types of habitat improvement for waterfowl can be conducted on islands 
and mud-flats. These are: planting agricultural crops, controlling woody com- 
petitors of native duck-foods, and sowing Italian ryegrass. 
On the higher open areas, particularly on islands, short-period agricultural 
crops can be planted to advantage. This has been demonstrated by Parker Smith 
of the Tennessee Division of Game and Fish (1948) and by others. Late July and 
August plantings of dwarf grain sorghum and buckwheat have been effective in 
attracting geese and ducks. 
The lower zone of growth on islands and mud-flats often inclines to become 
dominated by undesirable woody plants, mainly trumpetvine (Tecoma radicans). 
Cooperative studies with John Morse of the Kentucky Division of Game and Fish 
have revealed that this rapidly growing vine can be controlled by a spraying of 
05% of 2,l-D (Steenis, 1950). On the Kentucky Reservoir this control has resulted 
in an increase of chufa. The period for successful spraying of trumpetvine (on 
TVA reservoirs) is at the time of maximum runner growth, usually in September. 
A single spraying has resulted in 95% control. : 
On the lower exposed mud-flat areas, Italian ryegrass can be planted with 
success when the nights become cool in the fall of the year, usually from mid— 
September into October. Such plantings of ryegrass have yielded excellent results 
in attracting and holding waterfowl in TVA reservoirs in Kentucky, Tennessee, and 
Alabama. Preliminary studies made by Givens and Atkeson of the Wheeler Refuge 
have indicated that this grass will withstand flooding for two to three weeks 
during the winter months. Canada geese readily graze in Italian ryegrass when 
it is either submerged or unflooded. Ducks, particularly baldpates, have been 
noted feeding on it to some extent when the plants are not flooded and take it 
readily when submerged. Coots have been attracted by it into areas where normally 
they do not stay. 
Managing Marginal Marsh Vegetation 
The marsh vegetation on reservoir margins is ordinarily not of much value 
for waterfowl if the water is drawn down below this zone during the season when 
large numbers of the birds are present. However, the stranded plants or their 
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