INNERGATION®/ Saving water and a healthier vineyard
Do to the ongoing drought, water is in short supply now and probably in the future. With recent legislation signed by Governor Brown in California requiring groundwater monitoring, regulation could be in the near future. While drip systems are more efficient than others such as furrow or overhead, there is still much unnecessary waste due to poor infiltration, evaporation and hillside runoff. Surface drip also encourages shallow roots and weed growth. Subsurface irrigation is more efficient than surface drip, but it has problems such as clogged emitters, possible root intrusion, and not visible for inspection.
The Innergation® system approaches the problem from a different perspective. The specially designed drip tube hanger directs water away from the emitter several ways via spaghetti tube. The INNERGATION® DRIP CLIP in addition to suspending the drip tube allows water from 1 or 2 emitters via spaghetti tubes to be moved away from the vine encouraging longer root growth. For closely spaced vines, one drip tube hanger could support 2 spaghetti tubes. To reduce hillside runoff, a loop can be made with the 2 underneath holders so water can be directed to the upper side of the vine. The following thoughts would be more costly the 1st. year but could bring long term benefits in increased yield, less water and chemical use and healthier vines. It is then recommended making a depression or using perforated pipe to direct water underground. Moving water away from the emitter and running drip system will ease digging and may reduce root damage as they are likely concentrated under the emitter. Making a depression about the width and depth of a shovel would hold about 2 ½ gal. Filling the depression with compost helps vine nutrition and keeps out undesirable material. The porous texture of compost allows infiltration reducing evaporation. Mixing biochar with compost could add increased water retention characteristics. Gypsum or Lime could also be added to the mix to correct for pH. During each irrigation cycle, the depression with compost is filled and consequently drains afterward allowing atmosphere to replace the water. The compost would gradually be integrated into the soil, but the biochar would likely settle to the bottom of the depression, further positioning it for better water retention. With biochar in the bottom it may help prevent water from descending below the root zone. This makes room for more compost/ biochar to be added to the depression. Studies have shown that compost along with many different amendments can break down clay soils and increase permeability. Fertigation amendment use may be reduced as they are more quickly assimilated into the soil? An alternate method of subsurface irrigation is to use perforated pipe vertically in the ground. This would be especially helpful for hillside locations. A larger pipe 6” can be used in shorter lengths as it holds more water. A 3” or 4”size can be used for deeper penetration.
When smaller size is used, it may be more difficult to align the hole under the drip. The 6” pipe is easier to fill with compost. For more difficult hillside locations, the INNERGATION® PIPE CLIP is available to connect the spaghetti tube directly to the pipe. Soil texture may determine the length of perforated pipe used: heavy soils a longer piece; more porous soils, a shorter piece.
With these methods, water is directed into the soil. This will encourage deeper root
growth and make the vine less susceptible to weather fluctuations. Deeper root growth makes vines less susceptible to a number of diseases that prosper near the surface. As water is deposited directly into the soil, it is more readily available for root uptake; important for anticipated heat spikes and allows more control of the vine post veraision? Depending on the porosity of the soil and the run cycle of the drip system, surface moisture will be kept to a minimum; also reducing weed growth. With hillside vineyards, the texture of the soil is often vastly different from one location to another. Innergation® allows for working with vines on an individual basis via depression, pipe length; emitter output and amendments. Innergation could be easily adaptable to organic vineyards reducing labor for weed control and fewer amendments.
A good idea only has merit if it is financially viable. Through trial and error, strategies have been developed to reduce labor to a minimum. A hole can be augured in about 10 seconds. Rocky or dry soil will require more time. The perforated pipe can be inserted in about another 10 seconds if desired. A specially designed stand is available from Adams Knoll to cut the perforated pipe quickly, either in the shop or on site in the vineyard. A pressure washer can make a hole in about 15 to 20 seconds. Another method of using a pressure washer is to outline a circle or square about 10” in diameter or a square and penetrate about 4 to 6”. A shovel can then easily extract a large chunk of soil. Making the hole with a pressure washer has the added advantage that there is less chance of damaging a pipe that might be in the ground. An irrigation cycle could then fill the depression and then it will be easier to dig deeper. A tractor with a side mounted auger is another alternative. The side of the hole should be inspected for glazing after auguring as it might affect permeability? . Disclaimer
The thoughts expressed above have come from research and experimentation from Rick Adams and are subject to correction.