Spraying Tanks
San José scale and insects are everywhere making fruit growers spray their orchards. To get rid of the continual nuisance of leaks and the handling of warm solutions, orchardmen are building elevated concrete tanks and are heating the spraying solution with steam pipes on the tank bottoms. With such a plant, there is no delay—and time counts in the spraying season.
The tank shown stands on 10 by 12-inch columns, 6 feet clear of the ground. It has two compartments, each 5 by 5 feet by 4 feet deep holding 750 gallons. The side walls are 4 inches thick. Beneath the 4-inch bottom, on all sides, are 8 by 12-inch concrete beams.
Locate the tank convenient to the water supply. Dig the column holes 12 inches square, 3 feet deep, 11 feet out to out on the longer side and 5 feet on the shorter. Have all forms ready before placing any concrete. Fill the holes with concrete and imbed in each hole four ½-inch iron rods 10 feet long so that they will come right for the columns and extend through them. Set up the 10 by 12-inch by 6-foot column forms with their tops level with each other. Join them together with the solidly framed 8 by 12-inch beam forms.
Keeping the rods 1 inch from the corners, fill concrete in the column forms up to the floor beams. Spread 1 inch of concrete over the bottom of the beam forms and lay in two ½-inch rods 1½ inches from each side wall. Bend these rods around those in the columns. Without delay fill the beam forms.
Erect the forms for the tank proper as for [ Watering Tanks], page 74. In the bottom of each tank set a 1½-inch flange pipe coupling. Place 1 inch of concrete, then strips of heavy woven wire, and the remaining 3 inches of concrete. Fill the side walls and, 1 inch from the outside, imbed similar wire fencing. Protect the green concrete according to directions under watering tanks.
The materials required are: screened gravel or crushed rock, 4½ cubic yards; sand, 2¼ cubic yards; and Portland cement, 7½ barrels.
