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HOW TO USE IRRIGATION CHARTS
Irrigation charts are provided with each instrument. Additional charts are
available on order. Regular use of the charts helps in planning irrigation.
All readings should be recorded using a line of different identity to indicate the
readings of each particular block.
As readings are made and recorded, a curve of soil moisture changes will result.
By extending the slope of the lines, it will be possible to see well in advance
when the soil moisture will reach the level at which irrigation is required. In
addition, the chart will also indicate how much water is needed to restore the
moisture to field capacity.
To give an example, assume that irrigation should be applied when a block
planted at 18” and yielding a reading of 63, indicates roughly 1.5 in terms of bars
tension. Soon after irrigation, this block may read 96; a few days later (without
irrigation or rainfall) it may read 88; the next day 80. If these three readings are
plotted on the irrigation chart, and a line extended through them, it is possible to
project the time at which the 1.5 bars tension level (or irrigation point) will be
reached; in this case it would be less than three days.
INSTALLATION OF THE BLOCKS
1. Soak the blocks in water for 2
to 3 minutes.
2. Dig a hole in the ground with “1” soil auger or better, a 7/8” soil probe.
3. Make a soil and water slurry of creamy consistency and place 1 or 2
tablespoons of the slurry in the hole.
4. Push the block to the bottom of the hole, forcing the slurry to envelop the
block. The block can be pushed by using a tube (plastic or aluminum will
suffice) or a slotted rod.
5. Back fill the hole and tamp in small increments.
