WICC recently caught up with Stephen and Kerry Frost of Stonemeal Farm. The Frosts have been operating Stonemeal Farm in Narrikup since 1979 with a focus on minerals, soil biology and taking a hands off approach to the use of chemicals where possible. This highly productive farm has been studied by numerous experts to gain an insight into its success. The Frosts are recipients of the 2017 Australian Government Excellence in Sustainable Farm Practices Award.
WICC: There is a lot of discussion lately about regenerative agriculture. What do you see as the main principles of regen ag as everyone seems to have a different definition for it?
Stephen: In essence it means you are leaving the farm in a better condition. For us it is how we farm, it is the triple bottom line. You have the environmental, social and economic aspects. Regen ag is about increasing soil carbon, using less chemicals and allowing nature to do the work rather than chemicals.
WICC: How would you define your method of farming?
Stephen: There are lots of terms out there, biological, organic, regenerative. We are not organic. We use chemicals if we have to but only as a last resort. What we are doing is just trying to enhance nature to do its own things because we are just not smart enough to understand the interaction between all of the biology and minerals in the soil. We are farming the rhizosphere. It is a living soil. The problem is we have a complex biological system. You want to do a trial and bring all of those things together, well, the variables are just in the thousands. So I measure our success by our productivity. We have increased our soil carbon level by 1%. Our stocking rates are nearly double the district average. This year we got 27 rolls per hectare off our haylage on one of our paddocks with no nitrogen application. We had 130% lambing percentages out of merinos.
WICC: Tell us about the rhizosphere and how it impacts plant health?
Stephen: The rhizosphere is the interaction between the plant roots, and all the bacteria, fungi, algae and at the core of that is all of that is the mineralisation. We take a precautionary approach to anything that can negatively affect the health of the rhizosphere. Whatever goes on there is 99% responsible for what is going on… on top. We focus our management efforts on the rhizosphere.
When I studied soil science they talk about soil health being a three legged stool of chemistry, biology and physical but modern day farming is really just focussing on the chemistry.
WICC: Can you give us an example of how soil biology can benefit production?
Stephen: They reckon there is over 250,000 fungi species, we only know about 50,000… all of that is part of this rhizosphere. I will give you an example in legumes. Most farmers know that clover, which is a legume, fixes nitrogen. Clover fixes nitrogen through the rhizobia bacteria. On a root system of any legume are little nodules that form containing bacteria and when that plant dies the nitrogen in that rhizobia becomes available to plants.
WICC: What about trace elements. How important are they in production?
Stephen: You know a curious point about Denmark, they named a disease after Denmark. Denmark Wasting Disease which was a selenium deficiency. Denmark was known as sickness country by the Noongar people. It is highly leached country. The soil was leached of selenium, zinc, cobalt and copper and many other minor minerals due to the high rainfall. Only until they discovered the deficiencies was farming even viable along the coast right through to Walpole. Most of the early farms failed. If you go further inland the mineralisation is much higher because there was less leaching. Re-mineralising is a broad term but in essence farming production mines down on many minerals and conventional farming replaces only a few namely NPK, calcium and occasionally zinc and copper, yet there are so many other minerals that are required for productive pasture and healthy stock such as manganese, magnesium, selenium, cobalt, silicon, nickel to name a few. Even though some of these are only required in small concentrations....replacement is essential. Since we have been re-mineralising the soil we have found no requirement for stock mineral additives. We believe the most efficient way to get minerals back into our stock is through the soil... to pasture and fodder. We also manage our farms low pH soils without major lime applications, especially if calcium levels are ok on soil tests. The major focus for lime is on soils with higher aluminium levels. Over the decades we have been monitoring with soil tests and we have not seen a further dropping of pH in both top and sub soil. This has resulted in major cost savings. According to the Meat and Livestock Australia, lime and continuous super phosphate applications can lead to magnesium, copper, selenium and cobalt deficiencies.
To listen to Stephen's interview click here
