14 BUULETIN 1098, U. S. DEPARTMENT OF AGRICULTUEE. 



Removal of trees and stumps and cutting into suitable lengths for 

 hauling away: 



16 men, 8 days, at $1.25 $160. 00 



1 team and driver, 4 days, at $3 12. 00 



$172. 00 



Raking edges and burning trash, 4 men, 6 days, at $1 24. 00 



Fill or cross levee at dam, 6 teams and drivers, 5 days, at $3 90. 00 



Lumber for spillway, 7,000 square feet cypress, at $18 per M 126. 00 



Carpenter work on spillway : 



1 carpenter, 6 days, at $2.25 13.50 



1 helper, 6 days, at $1.50 9. 00 



2 helpers, 2 days, at $1 4. 00 



26. 50 



Total $611.00 



MAINTENANCE WORK FOLLOWING CLEARING AND CONSTRUCTION. 



A comparison of the cleared bayou, before the water backed up 

 over the bed, with the natural conditions that have already been 

 shown, may be made from the illustrations in Plate VII and Plate 

 VIII, Figure 1. These views were taken after the undergrowth had 

 been burned and the wood from the trees and logs had been hauled 

 away. Later in the year, at the onset of the winter rains, the water 

 began backing over the bed above the dam. This condition is shown 

 in Plate VIII, Figure 2. It is noted that quite an amount of debris 

 was floated to the surface. As the water level was raised, this float- 

 ing material collected along the margins, and this was cleaned out 

 with rakes and burned. The appearance of the bayou later in the 

 season, when filled with water, is shown in Plate VIII, Figure 3, 

 and Plate IX, Figure 1. 



The only maintenance work, in so far as vegetation is concerned, 

 was the clearing of the " floatage " along the banks following the 

 first rise of water and cutting back a comparatively small amount 

 of second growth, mostly grass {Zizamopsis miliacea) and willow 

 shoots that found their way to the surface of the water the follow- 

 ing spring. These shoots were removed by the use of a boat and a 

 curved knife on a long handle. Maintenance work has been re- 

 quired on the dam by reason of the work of crawfish, Camharus sp., 

 about the spillway, and this difficulty, as well as the effect of the 

 work of the crawfish on the water level above the dam, and in turn 

 the effect of the change in water level on the marginal vegetation, 

 will be discussed later. 



SURVEY OF ANOPHELES BREEDING AFTER IMPOUNDING. 



A comparison of the Anopheles breeding in the impounded area 

 and in the natural bayou is shown by the collections in the general 

 survey work for the years 1916 and 1917. The records for these col- 

 lections are listed in Table 7. 



