Working With Klamath County Soils

Transcription

1 Working With Klamath County Soils Richard Roseberg, Associate Professor OSU Klamath Basin Research & Extension Center Phone: Master Gardener Training March 7, 2012

2 Environmental Factors Influencing Plant Growth Temperature Moisture Supply Radiant Energy Atmospheric Composition Gas Content of the Soil Soil Reaction (ph) Soil Organic Compounds Biotic Factors Supply of Mineral Nutrients

3 Working With Your Soil Irrigation Water Management (water movement video) Plant Nutrition Soil Fertility (using soil biology & chemistry to your benefit) Supplemental Topics Soil Survey (practical understanding of your local soil and how to manage it) Measuring soil ph demonstration Taking a soil sample

4 Soil Fertility Background Plant Nutrition Soil Biological Effects & Nutrients Soil Chemical Effects & Nutrients Evaluating Nutrient Need Natural & Synthetic Fertilizer Sources, Labels & Costs Toxicity Concerns

5 History of Soil Fertility BC Mesopotamia & Egypt: Nutrient benefits of annual flooding, silt deposits & irrigation recorded. 300 BC Greece (Theophrastus): Manure rate recommendations depend on background soil fertility & water need of crop. Also compared value of various manure sources BC Greece & Rome (Xenophron, Cato, Columella, Virgil): Benefits of green manure crops esp. legumes.

6 History of Soil Fertility (cont.) AD 100 Rome (Pliny): Value & types of lime. Middle Ages- Many theories of plant growth, little good evidence or experimentation. Native Peoples- Various methods of fertility & crop rotation in N. & S. America, Asia, Africa. Oral or fragmented records mostly lost England & Germany: Many attempts to understand factors improving plant growth. Few crude experiments.

7 History of Soil Fertility (cont.) Modern Soil Fertility & Plant Nutrition Research 1835 Justus von Liebig (Germany): Many nutrients required in different amounts Rothamsted Experiment Station- Lawes & Gilbert (England): Modern crop nutrient research began. Established crop use rates of major nutrients. Late 1800 s Early 1900 s. Guano shipping industry from west coast arid tropics (excellent source of N & P).

8 Rothamsted, U.K. Long term rotation & fertilizer plots established 1843

9 History of Soil Fertility (cont.) Modern Soil Fertility & Plant Nutrition Research 1862 Morrill Act & 1887 Hatch Act (USA): Began state ag. experiment station crop research system s s Development of modern chemical fertilizer industry s - present: Revival of alternative & organic (actually traditional) methods of soil fertility & plant nutrition. Same time as development of precision agriculture.

10 Factors Affecting Soil Fertility (nutrients & soil health ) Parent Material Mineral Organic Matter Depth ph Soil Biology / Health

11 Required Plant Nutrients C, H, O, P, K, N, S, Ca, Fe, Mg, B, Mn, Cu, Zn, Mo, Co, Cl Essential Animal Nutrient: Se

12 Required Plant Nutrients & Sources C, H, O, P, K, N, S, Ca, Fe, Mg, B, Mn, Cu, Zn, Mo, Co, Cl Essential Animal Nutrient: Se Other growth factors Plant Growth Stimulators (hormones i.e. auxin, gibberelin, vitamin B1). Symbiotic organisms (rhizobia produce N, mycorrhizal fungi improve P & water uptake).

13 Parent Material (Native Fertility) Maps of Nutrients in PNW

14 Potassium

15 Phosphorus

16 Copper

17 Boron

18 Evaluating Nutrient Need Experience You can observe a lot just by watching. -Yogi Berra Nutrient Deficiency Symptoms Too late for this year! Confuse with other problems like herbicide damage? Crop Removal Calculations Test Kits or Meters Single or multiple nutrient? accurate? expensive? OSU Nutrient Management Guides (based on lab results) Web Site Examples

19 Nitrogen deficiency symptoms in tomato. (Epstein and Bloom 2004) Phosphorus deficiency symptoms in tomato. (Epstein and Bloom 2004)

20 Zinc deficiency symptoms in tomato. (Epstein and Bloom 2004) Boron deficiency symptoms in tomato. (Epstein and Bloom 2004)

21 Iron deficiency symptoms in tomato. (Epstein and Bloom 2004) Copper deficiency symptoms in tomato. (Epstein and Bloom 2004)

22 Plant Nutrient Uptake at Various Yield Levels

23 Soil and/or Plant Test Kits Relatively inexpensive, but only good for broad ranges. Some nutrients easier to measure than others.

24 Cardy Nitrate Meter (also have Na & K) Good accuracy & rapid, but fairly expensive and measures only 1 nutrient at a time.

25 Factors Affecting Nutrient Availability & Plant Uptake Biological Effects Occur on Several Size Scales Chemical Effects Control Availability of Some Nutrients Chemical and Biological Effects Interact to Determine Availability of Some Nutrients

26 ph Effect on Nutrient Availability

27 Living Organisms Plant roots physically alter soils and parent materials, decay products enhance chemical weathering and soil forming processes Animals alter their environment, dig, move, and bury soils and parent material Macroinvertebrates (insects, worms, nematodes), alter soils and plants Microorganisms digest plant and animal matter, creating acids and humus; they convert some plant nutrients from one form to another; organic acids weather soils and parent materials

28 Vesicular arbuscular mycorrhizal fungi (VAM) The VAM fungi use carbon from the plant to grow and make glomalin. In return, the fungi's hairlike filaments, called hyphae, extend the reach of plant roots. Hyphae function as pipes to funnel more water and nutrients particularly phosphorus to the plants

29 Factors Affecting Nutrient Availability & Plant Uptake Nutrients Controlled by Biological Processes

30 Bacteria Nitrogen Sulfur Biological Effects More Dominant Than Chemical (there is interaction)

31 Nitrogen Cycle Can treat legume seed with rhizobia bacteria to enhance N supply. Some absorption by plant roots.

32 SO 2 from combustion of fossil fuels.

33 Factors Affecting Nutrient Availability & Plant Uptake Phosphorus Controlled by Both Chemical & Biological Processes

34 Phosphorus Cycle

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36 Can sometimes treat seed with VAM fungi to enhance P uptake

37 Phosphorus Chemical Effects More Dominant Than Biological (there is interaction)

38 Phosphorus & Soil ph FePO 4 Fe 3 (PO 4 ) 2 AlPO 4 ppt ACID H 2 PO 4 - HPO 4 2- soluble NEUTRAL Ca 3 (PO 4 ) 2 ppt ALKALINE (basic)

39 Factors Affecting Nutrient Availability & Plant Uptake Nutrients Controlled Primarily by Chemical Processes

40 Potassium Cycle- mostly affected by soil mineral type

41 Minor Nutrients (transition metals) Fe, Mn, Cu, Zn ph (chemical) effect 2FeO + 2OH - Fe 2 O 3 + H 2 O 2FeO + H 2 O Fe 2 O 3 + 2H + Fe 2+ (soluble, absorbed) Fe 3+ (insoluble, not absorbed) Mn, Cu, Zn follow similar chemical reactions.

42 Chemical Effects Predominate Transition Metals Molybdenum & Boron

43 Crop Tolerance of Acidity / Alkalinty

44 Optimum soil ph range for some common crops.* Crop ph range Alfalfa Asparagus Azaleas and rhododendrons Beans Blueberries and cranberries Corn (field or silage) Fruit trees Garlic Grass for seed or pastures Crop ph range Onions Potatoes Small grains Sugarbeets Turf and pasture grass Vegetables *Determined using deionized water and a 1:2 soil:water ratio.

45 ph Greatly Affects Nutrient Availability in Soil, Crop Growth, and Toxicity of Some Elements

46 How to change soil ph? Reduce Acidity (increase ph or increase alkalinity) Increase ph with liming material (chemical effect) CaCO 3 Ca(OH) 2 CaO MgCO 3 All react with H + ions & Al 3+ ions Ex.: CO 3 + 2H + --> H 2 O + CO 2 Or: OH- + H + --> H 2 O

47 How to change soil ph? Increase Acidity (decrease ph or decrease alkalinity ) Decrease ph with acid forming material (biological effect) Elemental Sulfur: S + 4H 2 O --> 8H + + SO 4 2- NH 4 + form of nitrogen: 2NH O 2 --> 2NO H + Conifer Needles or similar organic material R-NH 2 NH 4 +

48 How Much Does It Take to Change ph? Using Limestone to increase ph Amount varies with soil buffering capacity. See SMP buffer test (OSU guide FG 52). Reaction time = few weeks ~ few months Using S to decrease ph Approx lb/ac S to lower ph 1.0 unit in medium textured soil. Time = 4~12 months

49 How measure ph? Test strips Cheap, but variable ph meter Accurate, but more expensive & require maintenance & chemical reagents Send to lab Accurate, less expensive for small number of samples, no maintenance, time delay

50 Using Commercial Lab for Complete Soil Nutrient Analysis Can be expensive. Time lag. High degree of accuracy. Detailed recommendations available from OSU & other universities

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53 Soil Nutrient Analysis & Recommendations Soil Sampling for Home Gardens and Small Acreages (EC628) General Case Soil Test Interpretation Guide (EC1478) Fertilizing Your Garden (EC1503) Fertilizing Lawns (EC1278) Specific Recommendation Exercise Sweet Corn (FG 62)

54 Example: Soil Test Report ph = 6.1 SMP = 6.5 NO 3 (0-2 ft) = 5 ppm; (2-4 ft) = 2 ppm P (Bray) = 19 P (Olsen) = 9 ppm K = 133 ppm Zn = 0.5 ppm S0 4 -S = 6 ppm B = 1.5 ppm

55 Fertilizer Sources, Labels, & Costs

56 Fertilizer Sources N is abundant (78% of atmosphere is N 2 ) High energy price to convert to NH 3 Few Natural Deposits of Ca(NO 3 ) 2 or NaNO 3 Organic sources- May be good source if available locally. K is abundant- huge deposits of KCl and K 2 SO 4, small KNO 3 deposits

57 S is abundant Fertilizer Sources Organic materials (manure, etc.) By-product of fossil fuel burning (S in coal, H 2 SO 4, acid rain) P is NOT abundant Ca 3 (PO4) 2 deposits limited (tropical coral, etc.) Organic Sources (guano etc.) limited Difficult to keep in a soluble form Excellent source is treated sewage effluent

58 Commercial Fertilizer Labels Examples: or N % N by weight P % P 2 O 5 by weight K % K 2 0 by weight S % S by weight Other nutrients?

59 Costs of Fertilizer Nutrients Example Fish Emulsion Labelled $8.00 / quart. 1 quart = 2.5 lb (assume 1 gal = 10 lb) 2.5 lb fert x 5%N (0.05) = lb N $8.00/0.125 lb N = $X?/ 1.0 lb N. (8.0 x 1.0) / = $64.00/lb N Costs can vary by 100-fold!

60 Manure Nutrient Sources

61 Unusual Nutrient Sources

62 Unusual Nutrient Sources-2

63 Unusual Nutrient Sources- 3

64 Carbon to Nitrogen Ratio in Organic Fertilizer Sources Some organic sources such as manure have a low C:N ratio Some organic sources such as grass clippings, sawdust, leaves, straw, etc. have a high C:N ratio. Problem: High C:N ratio materials will result in microbial activity tying up soil N for a period of time (from a few weeks to many weeks)-, making it unavailable to plants, causing a negative effect on plant growth.

65 Available N Immobilization / Availability of Soil N After Addition of Organic Matter (w/ Equal Total N) Low C:N Organic Matter High C:N Organic Matter Time

66 C:N Ratios Undisturbed Topsoil is about 10~12:1 Ideal compost is about 25~30:1 Addition of C:N greater than 30:1 will result in immobilization (decrease in available N) for a time. Addition of C:N less than 20:1 will result in rapid release (increase) of available N.

67 C:N Ratio of Selected Materials MATERIAL C:N MATERIAL C:N Bark 120:1 Paper 170:1 Coffee Grounds 20:1 Pine Needles 70:1 Cow Manure 20:1 Poultry Manure 6-10:1 Corn Stalks 60:1 Sawdust 500:1 Grass Clippings 20:1 Straw :1 Horse Manure 25:1 Vegetable Wastes 12-20:1 Leaves 60:1 Wood Chips :1 Legumes 15-20:1

68 Nutrient Mobility Through Soil Horizons

69 Nutrient Mobility PO 4 3- Ca 2+ Zn 2+ Fe 3+ Mn 4+ Mg 2+ Co 2+ Fe 2+ Cu 2+ Mn 2+ NH 4 + K + Cu + SO 4 2- MoO 4 2- SeO 4 2- BO 3 3- NO 3 - Cl -

70 Nutrient Mobility PO 4 3- Ca 2+ Zn 2+ Fe 3+ Mn 4+ Mg 2+ Co 2+ Fe 2+ Cu 2+ Mn 2+ NH 4 + K + Cu + SO 4 2- MoO 4 2- SeO 4 2- BO 3 3- NO 3 - Cl - So how do you apply them?

71 Even N can be toxic! Nutrient Toxicities Naturally high levels in soil or water: B, Mo, Na (and animal nutrient Se) Acid-induced nutrient toxicities: Al, Mn, Cu, Zn, Ni Old agric. chemicals/acid soil: Pb, As Industrial Pollution/acid soil: Cd, Pb, U, Hg, Cr Toxic (suppressive) Organic Compounds in Mulch (naturally-occurring or herbicide residue)

72 Thanks for your attention!