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indicated by the dated horizontal lines, were provided by

M. Duever (pers. comm.).

 Water levels in the study area over the sampling

period can be seen in Figure 38. Elevations of the pond

bottom at each station along the transect are indicated by

a labeled horizontal line. The hydroperiod, or period of

flooding, of any station is shown by the distance on the

horizontal scale between the points where the ascending and

descending water table line crosses the horizontal line

representing that station's elevation. Water depth is the

difference between the water-level line and the station

line at any point. According to the graph, the entire

transect was flooded from June 25, 1974, until early

February, 1975. Water depths along the transect remained

about 2 ft (60 cm) from late June through September 10,

1974. By October 29, they had receded to about 1 ft (30

cm), where they remained through early January, 1975. The

emergent vegetation bordering the pond (Station 100) was

the only remaining vegetation in standing water by February

25. The water line had receeded from the vegetation line

by early March, and the littoral zone was exposed by early

May. Only the center of the pond held water from May

through June 12. Water levels began rising in mid June,

1975, and the entire marsh transect had a shallow cover of

water by mid July.

 A comparison of Figure 38 with Figure 39, which is

based on water levels at Lake Trafford (U. S. Department of