44 BULLETIN 462, U. S. DEPARTMENT OF AGRICULTURE. 
others are plowed at right angles to these. When irrigation is begun, 
the men start at the far end of the main line, connecting a length 
of the 3-inch pipe to one of the valves and lightly screwing enough 
3-inch pipe together to reach the edge of the grove. The water is 
then turned on in furrows prepared previously. When it has run 
down a furrow about 125 feet it is stopped and made to flood the 
trees from the lower end up toward the pipe. When the trees have 
been well watered other lengths are unscrewed from the 3-inch pipe 
and the operation is repeated. When the top end of the grove is 
watered the same operation is repeated from the next hydrant on 
the main, which is situated 125 feet below. 
This method of irrigation has been satisfactory and seems to 
please the owner. Light portable pipe made of about 24-gauge gal- 
vanized iron 6 inches in diameter, instead of the 3-inch screw pipe, 
would have been more satisfactory, the iron screw pipe being heavy 
to shift. The cost of the plant is very low, but can not be stated 
exactly, as the material was purchased secondhand ; but such a system 
of all new piping would be very cheap, compared with the systems 
in general use in Florida. 
A* number of the systems in operation in Florida may be termed 
partial furrow systems. Some of these have distributing S3 7 stems 
similar to the hose systems already described, using hose to run the 
water down short furrows. Most of these, however, are supplied 
with heads of water too small to bring good results. 
In some instances the water is distributed over the grove entirely 
by means of portable pipe, there being no permanent mains what- 
ever. A notable example of this is in a grove near St. Petersburg, 
Fla. The plant waters 21 acres of full-grown orange and grape- 
fruit trees, some of which are over 30 years old and of enormous 
size. The soil is exceedingly loose and sandy, probably as porous 
as any of the grove lands in the State. The water supply is obtained 
from a deep bored well 8 inches in diameter and located in the high- 
est part of the orchard. The water rises in the well to within about 
50 feet of the surface. An impeller pump is used to lift the water 
from the well to the surface. This pump has a capacity of about 700 
gallons per minute and is operated by a 50-horsepower kerosene 
engine. The distributing system consists of 1,000 feet of 9-inch 
portable pipe of 24-gauge galvanized sheet iron in 10-foot lengths, 
constructed with taper ends so that one joint will fit into another 
like lengths of stovepipe. No other pipe of any kind is connected 
with the distributing system. 
The operation of this system is very simple, requiring the labor 
of only one man. The furrows are run down grade, three being 
made at one time by a contrivance devised by the owner of the grove. 
Other furrows run at right angles to these. When water is turned 
