Visit our NM Soil Health website: ( ) Section 1.

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1 Begin with the End Result that you want: i.e., Healthy Soil = Healthy & Productive Trees Presentation prepared by: Rudy Garcia USDA NRCS New Mexico State Agronomist Visit our NM Soil Health website: ( ) Section 1 Building Carbon What do we need to do, to build carbon in the soil? What to do to restore the biology, using management practices on saline soils. 1

2 Soil Improving Practices (1) Build soil carbon: Apply High Quality Compost & grow Cover Crops Feed the Soil Food Web Increase Biodiversity Promote optimal soil structure Reduce Compaction Soil Health Planning Principles: 1) Crop diversity 2) Living Roots 3) Cover the Soil 4) Less Disturbance Decrease soil borne pests/diseases/insect pressures Build aggregates, feed soil food web Reduce extremes in soil temperature; reduce evaporation Manage Salinity (2) Precision Irrigation & laser leveling Reduce soil disturbance (i.e., Physical, Chemical, & Biological) (3) Monitor Soil Conditions (lab analyses & Soil Health) (4) Nutrient Mgt. (Manage N/P/K) 2

3 Conventional Tillage in Pecans(Wind erosion: a problem on this sandy soil) Transitioning from Conventional Farming to a Soil Health Mgt. System Fields were converted from flood irrigation to micro sprinklers or sub surface drip. Conventional Tillage (Typical for most Pecan Orchards) Photo taken on September 8, 2013 (Anthony, NM) Restoring the living skin of the Soil Physical Disturbance Tillage Compaction Biological Disturbance Lack of Plant Diversity Over grazing Chemical Disturbance Misuse of fertilizer, pesticides, manures and soil amendments Pecan Orchard growing in a coarse sandy soil that was amended with compost and has Bermuda grass growing as a cover 3

4 Applying compost (2 nd application; top dressed) Several Acres of Compost wind rows Applied a total of 10 tons/acre High quality Fungal-driven compost. (Made with pecan wood chips, pecan shells, bales of Bermuda grass, and dairy manure.) Grasses in this orchard: Rescue, Fox tail Barely, Water grass, and a few others make a good cover. After two irrigations following mowing, grass residues are broken down (we need to consider not mowing so low). 4

5 Cover is mowed (to mimic gazing); residues decompose quickly. 5

6 Sandy Soil is beginning to develop soil structure & a Living Skin. Restoring the living skin of the Soil The Living Skin of the Soil RESTORES the Biological Spheres: 1) Rhizosphere 2) Aggregatusphere 3) Porosphere 4) Drilosphere 5) Detritusphere Managing the Soil Food Web: Earthworm This entails working to maintain favorable conditions of moisture, temperature, nutrients, ph, and aeration. It also involves providing a steady food source of raw organic material. Creating a Soil Habitat is the first step to managing soil biota for long-term soil health, and productivity. 0 4 depth: Zone of INTENSE Nutrient Cycling and Water use. Capillary water Macro Pore Soil biological processes are responsible for supplying approximately 75% of the plant available nitrogen and 65% of the available phosphorus in the soil. Like all organisms, those inhabiting your soil need food and a favorable environment. Adequate organic matter content, ample aeration, moderate moisture, neutral ph, and warm temperatures all favor increased microbial activity. 6

7 Diverse Soil Organisms = Healthy Soil (Are you feeding & caring for your Soil Livestock?) Biological: Living plants & Soil Food Web Soil Carbon Management Physical: Water stable Aggregates (Aggregates are the HOUSE, where Roots & Soil Organisms live.) Physical Biological Soil Health Chemical (Soil Solution) IMPORTANT: Plants (Roots) & Soil Organisms build the Aggregates Soil Solution: Soluble Nutrients & Soil Microorganisms (Nutrient Cycling: Biochemical/Chemical Reactions take place in the Soil Solution) The Soil Solution is held within the Aggregates Water stable Aggregates provide for the Optimal Chemical/Biochemical environment needed for Nutrient Cycling. Philosophy of Soil Health: is an attempt to bring together different aspects of the soil with the understanding that they are inter related and that they must operate in synergy for optimum and sustainable functioning of the soil media (Dr. John Idowu) 7

8 Section 2 IWM Converting from flood irrigation to Micro Sprinkler/drip irrigation Irrigation Water Management; How to manage for salinity problems. Must do a comprehensive analysis of all aspects of the specific site (Haney Test, SQTK, Soil Water and Tissue lab tests). Develop Case Study, Site Specific and work interdisciplinary. Pecan Orchard irrigated with sub-surface drip Subsurface Drip Irrigation 8

9 Soil Carbon & Water Management: Implementing a Soil Health Mgt. System to meet your Resource Concerns Major Emphasis: Manage for Optimum Soil Health (SOM), use Efficient Irrigation System & Irrigation Water Mgt. Plan Irrigation Water Management Managing for Soil Health (Soil Organic Matter); increasing Water Holding capacity, & improving Wateruse Efficiency. Abiquiu Dam, NM Elephant Butte Dam, NM Rio Grande: Photo taken April 21, 2015, at Anthony, NM Rudy Garcia, NM State Agronomist, USDA NRCS Storage Abiquiu Dam, NM Less River Water available Relying more on our Aquifers Reduction in Irrigation Water from our Reservoirs. Sodium Adsorption Ratio (SAR) 9

10 Pecan Roots Tensiometers: Are a soil moisture measurement device used to schedule irrigations. Pecan Orchard south of Las Cruces, NM. (Temperature measurements with and without cover. Taken on April 20, 2015 at about 2:00 pm) Surface Temperature: 77 0 F Surface Temperature: F Bare Soil and Soil with Cover were only a few feet apart. When Soil Temperatures reaches: Soil Temperature: 74 0 F at 1 inch depth Soil Temperature: F at 1 inch depth 10

11 Fruit Orchard with New Zealand White Clover as a permanent ground cover. (Plant Material Center, Los Lunas, NM) Evapotranspiration (ET) Irrigation Water Mgt. Goal: Manage ET for T, with minimal losses to E. GOAL: In a Healthy Soil, we want soil moisture to leave the system through Transpiration, NOT Evaporation. Also, we want cooler soil Temperatures during our hot growing season. In NM, we have found temperature difference of about 20 degrees Fahrenheit (with cover vs. bare soil) Net Irrigation Requirements = 44.0 inches/year Pecan Apr May Jun Jul Aug Sep Oct 11

12 Soil Stability (Slake Test) Soil Structure Evaluate your Irrigation Water Quality (e.g. Salinity, SAR, ph) & its Effects on Soil and/or Plants. Salinity Soluble Salts: (i.e., Standard Lab test Pocket Meter needed for evaluating mg/l of individual ions) SO 4 2- Cl - Na + Ca 2+ K + HCO 3 - CO 3 2- Mg 2+ NO 3 - Ca 2+ Mg 2+ K + Na + SO 4 2- Cl - HCO 3 - CO 3 2- NO 3 - Calcium Magnesium Potassium Sodium Sulfate Chloride Bicarbonate Carbonate Nitrate Soil Texture SAND ( mm) Silt ( mm) CLAY (< mm) 12

13 Dr. Jamie Iglesias, with Texas Agrilife Center, discussing soil profile characteristics, drainage, water & salinity management, and water table. Water Table Do you understand your soils profile characteristics? Open Drain: Adjacent fields have a shallow water table (i.e., within two-feet) Open Drain: Photo taken April 20, 2015, south of Las Cruces, NM. Salinity Problems due to shallow water table. (use Soil test to evaluate ECe, SAR, ph) 13

14 Managing for Soil Health (& Soil Organic Matter) in order to increase the Water Holding capacity & improve Water use Efficiency. An electron micrograph of Soil Aggregate, held together by carbon. Soil aggregates are a storage place for water, nutrients and soil micro organism Soil Aggregate (Porous & holds soil moisture) Factors affecting Nutrient Cycling & Soil Health: Temperature Aeration Soil Moisture Soluble Organic Carbon C:N ratio Salinity Sea Sponge (Porous & holds water) Healthy soil is like a Sponge: It can hold a lot of water. 14

15 Section 3 What are we going to analyze and what does it interpret (keep in context) Case by Case study & Site Specific when dealing with salt. Complexity of water quality is Highly Variable. Integrated Nutrient Management: evaluated through the lens of a Soil Health Mgt. System. Irrigation Water Sample for Nutrient and Soluble Salts Analysis Collecting Leaf Samples for Nutrient Analysis Collecting Soil Samples for Nutrient Analysis Evaluating Pecan Yield & Quality Haney CO 2 Test (Microbial activity) 15

16 Soils, Water & Tissue Tests. Total Cost/year/field: $120 to $175 (this does not include the Solvita Test) Nutrient Management: Irrigation Water, Soil & Plant Tissue Analysis for Pecan) Irrigation is by microsprinkler and subsurface drip (These fields were previously flood irrigated). Soil Analysis: Organic Matter = 0.6% (Low) Nitrogen Mineralized = 12.0 lbs./ac. Nitrate-N = 8.55 lbs./ac. (Low) Phosphorus = 5.0 ppm (Low) Potassium = ppm (Low) Sulfate-S = 20.7 ppm (Adequate) Calcium = 2,948.0 ppm (High) Magnesium = ppm (Low) Zn = 0.4 ppm (Low) Iron = 4.6 ppm (Low) Mn = 4.2 ppm (Low) Cu = 0.6 ppm (Adequate) B = 0.4 ppm (Low) Sodium = 2.6% of total CEC (good) 0 6 depth Soil Probe Pecan Plant Tissue Analysis: N = 2.66% Optimum: Sufficiency Range: % P = 0.12% Optimum: Sufficiency Range: % K = 0.95% Optimum: Sufficiency Range: % S = 0.22% Optimum: Sufficiency Range: % Ca = 1.21% Optimum: Sufficiency Range: % Mg = 0.31% Optimum: Sufficiency Range: % Zn = ppm Optimum: Sufficiency Range: ppm Fe = 135 ppm Optimum: Sufficiency Range: ppm Mn = 58.1 ppm Low: Sufficiency Range: ppm Cu = 5.8 ppm Low: Sufficiency Range: 9 30 ppm B = ppm High: Sufficiency Range: ppm Na = 0.02% Optimum: Sufficiency Range: 0 0.1% Concrete Ditch Sample at Midseason Sample midshoot leaflets/leaves Sample #: Water Quality Analysis Pounds per Acre: Nitrate-N = 12.2 Potassium = 89.5 Sulfate-S = Calcium = Magnesium = Sodium = Chloride = Bicarbonate = 1,911.4 Carbonate = 26.1 Iron = 9.3 Mn = 0.22 B = 1.31 Total Salts = 5,

17 Saline Soils: ECe > 4.0 ds/m ESP < 15 (or SAR < 13) ph < 8.5 Evaluate Salinity Effects on Soils and/or Plants. Precipitated Salts (e.g., Calcium Carbonate, Gypsum); Leaching Requirement, etc. Precipitated Calcite Crystals Saline-Sodic Soils: ECe > 4.0 ds/m ESP > 15 (or SAR > 13) ph < 8.5 Gypsum crystals Crystals precipitated in a void between clay particles. Calcareous Soil When acid is placed on a soil containing appreciable calcium carbonate, the soil fizzes in the form of carbon dioxide gas bubbles. Comparison of the crop salt tolerance between Cotton & Pecans at 25% Yield loss. 17

18 Soil Health Management System (Managing SOM) Soil Health: Integrating the Biological, Physical & Chemical components of the soil (i.e. Synergy between the Components) Biological Physical Chemical (Orchard with a cover: soil has an Optimal Bio Geo Chemical Nutrient Cycle) Grass is mowed several times during the growing season (residues are left on the surface to decompose & recycle back to the soil) Bare Surface (poor nutrient cycling) Grass Roots Macroaggregate ( mm dia.) Microaggregate (< 0.3 mm dia.) Consisting of Clay, silt, humus, particulate organic matter, very fine sand. White areas indicating presence of glomalin (Dr. Kris Nichols, USDA/ARS Mandan, ND) O Oxygen 2 (O 2 gas in macro pores) Soil Health Planning Principles: 1) Plant Diversity (Cash Crop & Cover Crops) 2) Living Roots throughout the year 3) Cover the Soil with Plants/Crop Residues 4) Minimal Biological, Physical & Chemical disturbance 5) Grazing where applicable Soil Solution (the Soil Solution is held within the Macroaggregates & Microaggregates) Dissolved Oxygen & Carbon Dioxide Mineralization O 2 CO 2 (Microorganisms are Sub Aquatic Organisms) Immobilization Soluble Nutrients (e.g., OC, ON, OP, NH 4+, NO 3-, other: K +, Ca 2+, etc.) CO 2 Carbon Dioxide (CO 2 gas in macro pores) Factors affecting Nutrient Cycling & Soil Health: Temperature Aeration Soil Moisture Soluble Organic Carbon C:N ratio Salinity 18

19 Section 4 Summery showing the proof of concepts and progress. Creating a functioning Soil Health field is an ART and SCIENCE of SOIL HEALTH. Has a STEEP LEARNING CURVE of these PRINCIPLES. There is NO replacement for Knowledge, Skills and Ability (KSA s) Yield and Quality 19

20 Pecan Orchard irrigated with sub-surface drip Nut Quality N inputs have been reduced from 200 units/ac to 125 units/ac on mature orchards. Phosphorus inputs have been reduced by up to 40%. Zinc applications have been reduced from 5 to 3 foliar applications. Leaf samples are showing sufficient levels for all nutrients. And soil health is improving significantly (i.e., earthworms, water stable aggregates, higher OM, healthier trees, etc.) Section 5 Where do we go from here? This is a work in progress; we have much more to learn and understand about how the soil health functions with salts. Termendous learning curve is quite steep. 20

21 Conventionally Tilled Soil Infiltration Test Soil Infiltration Test No Till (Mowed) Fungal hyphae binding soil particles together into aggregates. Arbuscular Mycorrhizal fungi produces Glomalin that glues soil particles together. Fungal Hyphae Fungal Hyphae with Glomalin Glomalin is a stable glycoprotein, that stores carbon in the soil as a glue and protects the soil biota. Mycorrhizosphere (Glomalin) Soil Humus Formation: 1) Photosynthesis 2) Resynthesis 3) Exudation 4) Humification Dr. Christine Jones Rhizosphere Narrow region of soil directly around roots. Living roots release many types of organic materials. These compounds attract Bacteria that feed on the proteins & sugars. Crop Residues are NOT the Major Source of OM for Building Soil Humus 21

22 Mycorrhizae Fungi, Soil Humus & Nutrient Density of Crops & Animals. Notice extensive Mycorrhizae network on coarse sand grains. Dr. Christine Jones Mycorrhizae on Coarse Sandy Soil (Photo: Michael Melendrez) In a Humus Rich Soil, Plant obtain all their CO 2 from soil (We want to recycle all nutrients, including CO 2 ). 22

23 Soil Organic Matter is the House microbes live in, Water Extractable Organic Carbon is the Food they eat. 2% SOM (12,000 ppm Carbon) 100 1,000 ppm Carbon from water extract = Microbial Food Dr. Rick Haney Initially, on some fields, Bermuda grass was planted and did well on the sandy fields. This works We are learning from our mistakes However, after several years, we observed that harvesting/bailing the grass was removing too much energy/carbon from the system. Now we are looking at different grasses and legume plants, with the goal of mowing them as needed and leaving the residues in place. This does NOT work 23

24 Rudy Garcia USDA NRCS New Mexico State Agronomist (505) Thank You Clarence L. Chavez Soil Scientist Los Lunas, New Mexico HM Cell