areas; (2) providing non-flooded farm crops; (3) controlling erosion in 
waterfowl habitat; (4) improving islands and mud flats; (5) managing marginal 
marsh vegetation; and (6) planting aquatics. 
Developing Sub~Impoundments and Dewatered Areas 
Two types of sub—impoundments can be used effectively for waterfowl. 
In one, water of fairly constant level is present continually, while in the 
other, water levels drop considerably or completely in summer, followed by 
reflooding during late fall. 
Stable-Water Units 
; In permanent pools or sub~impoundments, useful marsh and aquatic 
vegetation can be produced. Such developments for waterfowl have to be 
confined to those sections of the Kentucky Reservoir where human occupancy 
is limited during the malaria breeding season. Fortunately, these restricted 
areas include choice potential waterfowl sites where shallow inundation of 
the valley floor results in an alternating land and water arrangement with 
many low emergent ridges or natural levees. These sites afford excellent 
opportunities to dike off channels for enclosing back-water units that are 
well suited for marsh and aquatic habitat. The embayment areas of the 
reservoir, in these restricted zones, also provide opportunities to impound 
small shallow-water units of the farm-pond type advocated by the Soil 
Conservation Service. : 
The value of good feeding grounds for ducks adjoining large, 
comparatively sterile expanses of water is considerable. Large units of 
water attract waterfowl and serve as loafing sites, but adjoining feeding 
places of quality are necessary in order to hold the birds. This relation- 
ship has been exemplified on Hematite Lake, an impoundment on the Kentucky 
Woodlands National Wildlife Refuge. In 19h4-l6 ninety percent of this lake 
was open deep water and ten percent consisted of excellent marsh and aquatic 
vegetation, mainly in the upper shoal-water zone. At this time the whole 
lake was extensively used by ducks. These observations denote that in the 
TVA region the value of an area having useful marsh and aquatic vegetation 
may be increased ten-fold when complemented by an open expanse of water; 
and vice versa, the usefulness of a large open-water area is likely to be 
increased greatly by the presence of good food sources available in the 
immediate vicinity. 
Propagation studies on marsh and aquatic plants in small water units 
were made with Preston Lane at the Kentucky Woodlands National Wildlife 
Refuge and later continued on an experimental sub-impoundment of the Kentucky 
Reservoir. Sowing of wild millet and largeseed smartweed improved the marsh 
margins. Longleaf pondweed was readily propagated by live-stem planting 
which resulted in aggressive growths that fruited profusely. Successful 
results were also obtained with narrow-leafed pondweed (Potamogeton 
usillus), using winter buds for propagation. Introduction of watershield 
tarisents schreberi) was only partially successful. Plantings of rootstocks 
of this species were effective when made in water six inches or less in 
