Modified on 12 August 2020
Sandy loams are inherently low in organic matter and of a particle size that is prone to rapid drainage of irrigation water. They are ideal for golf course greens where the need for a rich turf that is dry underfoot but with high water retention in the root zone to promote solid root development.
With such a high friability, root growth is very efficient leading, eventually, to the formation an impenetrable thatch binding of the roots preventing water infiltration. This then leads to the use of mechanical decongesting solutions and organic surfactants to assist in drainage and infiltration.
For irrigated orchards, it is always a challenge to maintain the required irrigation at the younger developing surface roots let alone to direct water to the main anchor roots of the trees. Sandy loams reach their fill capacity quickly and their runoff occurs through drainage to the lowest point of the field.
In both cases, where modern fertigation systems are employed, little attention is given to preparing the soil to receive the active ingredients that is normally deployed as a solution in water.
At CHT we have turned our attention to the charge balance of the sandy loam, with the expectation that raising the cationic charge of the sand particle will cause the connecting water droplet to be moved away in a lateral direction in the first instance.
Field trials support this hypothesis and show this movement translates in the reduction in fill potential at the drip impingement point avoiding early drainage and directing the water fill sideways between drip point zones much more efficiently. The trial reports may be accessed here:
- Boundary Bend Sandy Loam and Robinvale Clay Loam ( pages)
- Interim Report for Almond Grower (Rmonpro Developments)’ – (to be attached when ready).
Long term trials also show the effect of the Aqua-Sil treatments are long lived.
Whether it is fertilizer runoff, loss of irrigation water or cost mitigation of the fertigation system as whole, the reliance on a liquid system to deploy liquid organic matter such as humic acids and NPK solutions, the prepartion the soil for better water retention should be seriously considered.
Almost all liquid born systems are short lived until and unless a significant change to the nature of the sandy loam is made. This required change can now be made with the application of Aqua-Sil Techology.
Water movement through Sandy loam from Garden Centre.
( top view )