38 BULLETIN 462, U. S. DEPARTMENT OF AGRICULTURE. 
however, that to erect an overhead system for the irrigation of most 
of the field crops, where a yearly profit of $50 per acre is supposed 
to be good, would be to lose money from the beginning. In any case, 
the farmer should look into his conditions carefully before irrigating, 
and be very sure that he can not get results from cheaper methods. 
In many cases he will find that he can not, but there are many cases 
where he can, and it should be his first duty to investigate. 
THE FURROW METHOD AND OTHER SYSTEMS USED FOR IRRIGATING TRUCK. 
The two systems of subirrigation already described and the several 
systems of overhead spray include 80 to 90 per cent of the area of 
irrigated truck in the State. The remainder is covered by various, 
methods coming under the common designation of surface irrigation. 
The largest area of garden crops irrigated by surface methods is in 
Manatee County, where it is estimated that 1,000 to 1.500 acres are 
irrigated in this way. A small acreage of strawberries in Hillsboro 
County is irrigated by surface methods. Other patches are scattered 
through the State, probably totaling not more than 500 acres. 
The methods employed are very simple in most cases, many of the 
farmers running water in open ditches and letting it flow down be- 
tween the rows, regulating the flow by means of a shovelful of soil 
at the head of the furrow. Some farmers use lengths of hose to aid 
the flow in the furrows, while others use light-weight pipe to convey 
water over the field. The objections to these systems are that they 
are wasteful of water, and that there is a considerable amount of 
labor attached to their operation. The possibilities in irrigation by 
the furrow method are worthy of careful consideration and doubtless 
it will become much more popular when better methods of distribu- 
tion are employed. 
IRRIGATION 1 OF CITRUS GROVES. 
The need of moisture for citrus trees was taken up to some extent 
under the discussion of soil tests. It was shown that the soil is com- 
monly very diw for long periods, producing a harmful effect on the 
trees. 
In order to determine the benefits accruing from the irrigation of 
citrus groves, a portable pumping plant was procured which could be 
taken from one grove to another. Such a plant will irrigate one or 
two rows in an unirrigated grove; and the difference in yield and 
quality of the fruit is observed later in the season. In this way exact 
data may be obtained which will give the farmer some foundation on 
which to estimate the allowable cost of applying water to the tree. 
No definite data have yet been obtained. 
A great many orange and grapefruit growers claim that the benefits 
from irrigation are not worth the expense of installing and maintain- 
