The cotton crop on a farm at Rowena NSW was planted into fields with soils that are highly sodic. The fields had a pH of 9.8 due to the high sodium levels in the bore water that irrigates the fields.
TM Agricultural was applied at 500ml/ha along with pH Adjuster at 500ml/ha to the fields pre-plant in September 2019. The second in-crop application of the same rate of both TM Agricultural and pH Adjuster was applied to the fields in December 2019 with an in-crop Roundup Ready application.
pH and Penetrometer Readings of the cotton crop
When I examined the cotton crop fields in March 2020 the vigor of the crop and its robust health was clearly evident. The pH meter showed that the pH of the soil had reduced to 6.2 and 6.6 in each of the fields. Optimum plant nutrient availability is achieved when the pH is between 6 and 6.5.
The penetrometer readings in both fields ranged from 190 to 220 psi (see photos) which indicates that plant roots will have good growth patterns when soil penetrometer readings are less than 200 psi. When pressure is greater than 300 psi the plant is required to force the tip through the soil which leads to issues such as poor root growth that means less nutrient and water absorption which leads to reduced yield.
The root systems of the cotton crop plants were straight indicating they were not trying to push through a compaction layer. This is reflected in the penetrometer readings and the neutral pH of the soil. The root systems had many fine feeder roots and some rhizosheaths (which gives a dreadlock appearance). This indicates a higher presence of soil microbiology and microbe glues that are allowing the soil to adhere to the roots to solubilise soil the nutrients efficiently while also improving the development of the soil structure, soil aeration, and drainage.
Overall, the TM Agricultural and pH Adjuster applications have activated and repopulated the native soil microbes in the soil which have improved both the soil and the plant health by lowering the pH to a neutral level and improving the soil structure. The pH Adjuster, consisting of kelp and a very refined form of fulvic acid which is an inorganic electrolyte that is both positively and negatively charged. Fulvic acid is so strong that it is capable of carrying over 73 elements, which will boost cation exchange this allows crops to balance soil pH naturally. Because of its dual charge, it is an amazing chelating agent. Meaning that it can move leeched and locked up salts in the soil, allowing for them to be purged and nutrients to become readily available to crops. Fulvic acid works even better when combined with seaweed extracts. Seaweed extracts are loaded with natural plant-growth hormones such as auxins and cytokinins. Fulvic acid holds onto the auxins in an exchangeable form to amplify their effects on plants.
When used in conjunction with Best products such as TM Agricultural and a foliar fertiliser, pH Adjuster will drastically increase microbial stimulation efficacy by stimulating plant metabolism, increasing enzyme activity, and acting as a catalyst for plant respiration, it also improves nutrient efficiency as it enhances the permeability of cell membranes.
Keiran Knight B.Bus (Ag Comm)
Agronomist Best Environmental Technologies Pty Ltd