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shallow and flowing wells. In localities where flowing wells are possible, this is the cheapest source of water for watering celery. We occasionally find a location where the water can be brought from some higher elevation and delivered in the celery fields by gravitation, but, as a rule, some form of pumping machinery to lift and deliver the water will be required. Where the lift is not great-that is, not over 20 feet in all-the pumping can very easily be done by means of some form of rotary or centrifugal pump which may be driven either by a steam or gasoline engine.

Quantity of Water Required. The quantity of water required for the production of a crop of celery is in most cases not great, and rarely exceeds 5 inches over the entire surface during the period of growth in the field. The application of five waterings of I inch each to an acre will require the handling of 136,000 gallons of water, or a little over 27,000 gallons at a watering. This is not a large amount of water for handling by a large pump and the cost of applying will vary under different conditions. As a rule the actual cost of watering an acre of celery, if the work is done on a comparatively large scale, should not exceed $1 an acre for each watering, or $5 for the entire season. Celery requires the most water at the time when it is making its greatest growth, which occurs late in the summer. As the crop approaches maturity, the water should be applied sparingly, as the soil evaporation is not so great at that time of the year, and when the soil becomes too moist it is difficult

to get it dry enough to work. Excessive moisture. in the soil at the end of the season will invariably produce celery of inferior flavor and poor shipping qualities.

Irrigation on Muck Soils.-On low lying peat or muck soils, it may not be necessary to apply any water in addition to the natural rainfall, but irrigation is almost indispensable on clay or sandy upland soils. Muck or peat soils are generally located in a basin or depression of the surrounding soil formation, and by pumping on water continuously the muck will absorb it until saturated and the water will rise almost to the surface. This should be avoided as the soil will become water-logged and the celery plants will be permanently injured. If it is found that sufficient moisture cannot be maintained in the surface soil by frequent shallow cultivation, it may then be necessary to resort to irrigation, but some form of surface irrigation is preferable to flooding the muck basin and raising the water table in the soil. The underlying muck, which has not been exposed to the action of the air for centuries, is filled with the acids of decaying vegetable matter, and these acids are injurious to the roots of plants with which they come in contact.

Methods of Irrigating.-There are three principal systems of irrigation used by the celery growers of this country: (1) surface ditches, (2) overhead sprinklers, and (3) subirrigation. Each of these systems has its adaptations and limitations which determine the possibility of its employment under given conditions.

Wooden Flumes and Open Ditches.-Where the open ditch system of distributing the water is employed, the water can be conveyed from the pump to the ditches by means of a long wooden trough constructed by nailing three planks together and leaving the top open. Where a large field is to be watered, the trough or flume may be run entirely along one side and secondary flumes taken off at intervals to distribute the water to the ditches. The secondary or distributing flumes should cross the ditches and be raised about I foot from the ground, openings being provided in the bottom of the flume for the discharge of the water into the ditches. The openings or traps in the bottom of the flume should be cut with sloping edges and a piece of plank having the same shape fitted to them in order to stop the flow of water into any particular ditch. Where the distributing flumes join the main flume they should be provided with gates to control the water, or the end of the distributing flume may be placed beneath the main flume and the water discharged through a trap in the bottom of the main flume. The flumes will necessarily be supported upon trestles or posts set in the ground and the end next the pump must be raised several feet, unless the ground slopes naturally, in order that the water may flow freely through the flumes and into the ditches.

Iron pipes may be employed instead of the wood flumes, numerous tees being inserted in the lines of pipe for the discharge of the water. These openings should be plugged and the plugs removed

when it is desired to attach a piece of hose at the opening for filling the ditches within reach; the hose may then be detached, the plug replaced, and the hose moved to the next opening. With a hose 50 feet long it will only be necessary to have the openings every 100 feet along the line of pipe. Valves will be found more desirable than plugs for closing the openings, but their use adds considerably to the expense of installation. A threaded nipple should be inserted in one end of the hose for attaching it to the pipe, and one and one-fourthinch hose will be found to be the most convenient size for general use.

The iron pipes are more desirable than the wooden flumes, as they can be laid upon the ground or on blocks and do not require leveling or grading, the only requisite being that the source of supply of the water be somewhat higher than the delivery openings, or that the water be driven through the pipes under pressure. In the autumn, after the irrigation work is finished, the pipes should be carefully drained to prevent freezing, or be disconnected and placed under shelter until the following season. Galvanized pipes are preferable, or if black pipe be employed it should be painted on the outside with mineral paint or asphaltum varnish from time to time to prevent rusting.

Overhead Sprinkler Systems.-One of the most satisfactory methods of applying water to the surface of the soil is the deluge sprinkler system. By this method, lines of iron pipes are laid on the surface of the soil 16 or 18 feet apart, with upright

pipes about 3 feet high every 16 or 18 feet along their length. At the top of each upright is placed a distributer, known as a deluge sprinkler, which will spread the water very evenly over the entire surface between the uprights. This system has its disadvantages; it is costly to install, the lines of pipe and uprights are in the way of cultivation, and the

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pipes must be taken up at the end of each season and relaid at the beginning of the next.

The expense of pumping is greater than for the open ditch system, as the water must be driven through the pipes under a pressure of at least 50 pounds to the square inch in order that the sprinklers will distribute it uniformly. An eight to tenhorse power pump, with a three-inch suction

and two and one-half-inch discharge pipe, will be required to operate 16 of these sprinklers at one time, but these will thoroughly soak an area of about 20 square rods every 15 minutes, or I acre every two

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