36 BULLETIN 462, TJ. S. DEPARTMENT OE AGRICULTURE. 



started again with little trouble. The manufacturers of both types 

 have sought devices that would prevent the clogging of the nozzles, 

 and improvements are being made constantly for both. The larger 

 amounts of water applied per minute is one of the main advantages 

 claimed by the advocates of the whirling-nozzle type, the opinion 

 being that more water is needed for the east-coast soils than is com- 

 monly supplied by the overhead-pipe system. This is denied by users 

 of the latter system, who claim they get good results, and in any case 

 could get more water by placing the nozzles closer together and using 

 larger lateral pipe. Probably the main difference in the system is 

 that the overhead-pipe system must have posts placed in the field, 

 which are more or less of a nuisance, some trouble to keep up, and 

 are often unsightly, especially in Florida, where it is common prac- 

 tice to use posts that are cut on the farm. The other systems present 

 a much neater appearance, which is especially pleasing in the case 

 of the irrigation of a flower garden or a private winter estate. For 

 this reason, many of the large estates near Miami are watered by 

 these systems on this account. The matter of appearance, however, 

 is of little importance to most irrigators. 



There is a great difference in cost, which often is of primary im- 

 portance. Some of the systems covered by the old stationary noz- 

 zles, used for watering gardens, have cost more than $500 per acre. 

 This high cost is due to the necessity of placing lateral lines close 

 together. From $200 to $500 per acre probably would be an average 

 cost for a complete system for a 5 to 10 acre truck patch. The aver- 

 age rotating-nozzle type will average $200 to $350 per acre installed, 

 and the overhead-pipe system $175 to $275. Some of the stationary- 

 nozzle systems are not liable to get out of order, and will accommo- 

 date almost any kind of dirty water. Other rotating-nozzle and 

 overhead-pipe systems do not operate well unless the water is clear. 



The distribution of water is better effected by the overhead-pipe 

 system than by any other, being practically perfect if the lines 

 are turned at the proper time. Distribution by the whirling noz- 

 zles depends considerably on the wind. If there is a good breeze 

 the distribution will be even, but if the air is still there is unevenness 

 in watering on account of the untouched spaces between adjacent cir- 

 cular watered spaces. The smaller nozzles of the overhead-pipe type 

 apply water in fine drops, which is of considerable benefit in some 

 localities, but it is doubtful if this makes any appreciable difference 

 in the sandy soils of Florida. 



The advantages of the overhead-spray systems are many, the chief 

 ones being the ease of irrigation and the absolute lack of manual 

 labor attached. The rapidity of applying the water and the evenness 

 of distribution are of great importance, especially at the time of set- 



