by Jerry Brunetti
Over the years, my work has encompassed a wide range of both agronomic and horticultural arenas and they all provide living laboratories and great learning opportunities. Consulting for those engaged in agricultural or horticultural pursuits that range from very conventional to very organic has provided additional insights that expedite the learning process.
Dairy farmers obviously focus on certain particulars that produce growers do not and vice versa. However, when they both share a common concern about the productivity of their soil their approaches may not differ all that much. On the other hand, someone plugged into conventional N-P-K and petrochemical methods will have quite a different approach than an organic grower who depends upon crop rotations, cover crops, compost and low analysis amendments. None the less, everyone involved in horticulture and agriculture is subject to inevitable challenges associated either with the specific progression they are in or their actual production methods.
Audit the “Vital Force”
My approach is to utilize a biological and ecological compass to ascertain what methodologies to production or solving a problem are best. One has to take the pulse of the landscape and ask, as my mentor Don Schrieffer would ask, “What are your yield (or “health” in the case of animals) limiting factors?” Is it soil compaction? Inadequate calcium? A dearth of biodiversity? In essence one has to audit the “vital force” of the landscape.
Soil Analysis
I begin by utilizing a comprehensive Melich II soil analysis which measures macro elements (Ca, P, Mg, K, S), cation exchange capacity, pH, organic matter, and trace elements (Fe, Mn, Zn, Cu, B, Mo, Co, Se, Cr, Si). If necessary, I’ll check the water soluble nutrients as well and also monitor the composition of irrigation water (total dissolved solids {TDS), carbonates, bicarbonates, sulfates, minerals, etc). The final “report card” of the soil is obtained by conducting a tissue test to measure the macro and micro elements and kinds of carbohydrates. Livestock require more detailed information, and tissue testing should include digestibility and energy levels.
On Site Testing
The lab isn’t the only place to conduct testing. Therefore somebody needs to walk and inspect the land. I utilize a soil penetrometer to measure compaction of the soil in pounds per square inch (psi). Compaction levels above 200 psi lead to a myriad of problems including poor root development and consequently an anaerobic zone, poor water infiltration, and reduced tolerance to heat and drought conditions. I dig a hole one foot square and one foot deep (total of 1 cubic foot) and check for earthworm activity. A healthy yield of 25 earthworms or one million per acre can produce 60,000 lbs of castings/acre/year!
The cardinal rule I abide by is to only apply what the soil and crop need and avoid applying what they don’t need. This not only improves productivity and increases resistance to pests but is also a more economical approach than haphazard applications which aren’t based on sound testing. If the tissue tests show a deficiency of important elements, then applying a foliar spray to meet those needs can be quite successful. Usually, I recommend a base mix of biologicals such as fish emulsion, kelp extract, humates, vermicompost, and molasses “spiked” with those nutrients that are in short supply along with a source of calcium to help move those nutrients into the tissue.
Adhering to Principles
Whether one is dealing with turf, trees, tomatoes, or turkeys, certain biological principles must be adhered to, regardless if one is organic, conventional or a combination of both. Those principles are: nutrition (geology/minerals); biology (the correct balance of bacteria, fungi, protozoa, anthropods, earthworms, etc) called the “food web”; and the proper physical management of soils whether they are loam, clay or sand, with humus being the most important consideration to improve the buffering properties of soils.
“The proof of the pudding is in the eating.” This adage is certainly appropriate for produce where quality is demonstrated through flavor and shelf life. With livestock the proof is their production, reproduction, and longevity. In the lawn and landscape arena, it’s the amount of resistance to stresses induced by weather extremes, the immunity to pests, and the “staying power” (e.g. turf turgor) which is evident in hand testing methods such as sap pH, color and conductivity, BRIX (sugar) of the sap and so forth.
In summary, a combination of physical observation, on site determinations and laboratory analysis provide the information needed to make informed and enlightened decisions about the ecosystem one is attempting to steward.
About the Author
Jerry Brunetti founded Agri-Dynamics in 1979 to provide holistic animal remedies to farm livestock, equine, and pets and continues to work toward improving soil and crop quality, livestock performance, and health on certified organic farms. In 1991, he co-founded Earthworks Natural Organic Products to provide products and consulting services that encourage the implementation of ecological principles of balancing soils, reduction in the use of pesticides, and elimination of dependence on chemical fertilizers within the golf course and landscaping industries.
Jerry will present “What Do Minerals Do?” and “Biology, Chemistry, and Physics: The Healthy Soil Triangle” at the ELA Conference & Eco-Marketplace on March 3. He can be found online at www.agri-dynamics.com.
