IRRIGATION IN FLORIDA. 33 
Many of the cucumber growers use an ingenious device for protec- 
tion against frost. When indications point to coming frost the 
young plants are covered with wooden troughs 10 to 14 feet long, 
made of two 1 by 9 inch or 1 by 10 inch boards nailed together in 
the form of a V. These troughs are removed the next day, and 
when not in use, are allowed to lie between the rows. About 
10,000 feet of lumber is required to protect an acre of vines, costing 
about $120 to $160. This is in addition to the average cost of $250 
for an irrigation plant, making an outlay of $400 per acre, exclusive 
of the cost of the well, the land, and the growing of the crop. The 
common use of troughs for protection against frost on the same 
lands that are irrigated by overhead systems indicates the unwilling- 
ness of the growers to rely on spray irrigation for protection against 
loss from cold weather. 
Another section of interest where overhead irrigation is practiced 
is in the vicinity of Bartow and Fort Meade in Polk County, 60 
miles south of the Sumter County trucking section. About 450 acres 
are irrigated in this district. The chief crops are lettuce, cabbage, 
tomatoes, and eggplant, their importance being about in the order 
named. A good summer crop is sweet potatoes, which often yields 
heavily. 
The average size of these irrigated farms is somewhat larger 
than that of the northern counties, being about 20 to 25 acres. 
One overhead-spray s}^stem covers an area of 100 acres. On this 
farm the water is supplied to the mains from bored wells by three 
gasoline engines and three 2-stage centrifugal pumps. 
The owner irrigates about once a week during dry weather, giving 
the ground a good watering at each irrigation. He starts his engine 
late in the afternoon, running them 8 to 10 hours. This irrigation is 
equivalent to approximately 1 inch of rainfall. He says that he 
would not attempt truck farming without such a system, which he 
finds valuable at the time of setting the young plants and again at 
the time of maturing them. He uses small pasteboard boxes for cov^ 
ering young tomato plants when cold weather is expected. Some 
farmers, be fore an expected frost, cover the small plants with soil, un- 
covering them the next morning. Thus, in this section also, overhead 
systems are not generally used for protection against frost. The 
small cardboard boxes are cheaper than the troughs used at Bush- 
nell, and are not such an impediment to cultivation when not in use. 
A detailed description of other examples of overhead-pipe systems 
would be of doubtful value on account of their similarity to those 
already described. Probably 1,500 acres under other overhead-pipe 
systems are distributed over the State, several hundred being scat- 
tered through Manatee and Hillsboro Counties, mostly in small 
