Soils and Organic Fertility Management

Warren Roberts

George Kuepper

Last Class - Soil ManagementSite Selection, Soil Fertility

Warren Roberts

George Kuepper

Ideal Soil

• 50% Solid Matter

• 45% Mineral

• 5% Organic

• 50% Pore Space

• 25% Water

• 25% Air

Soil Fertility

• Essential Plant Nutrients

• C HOPKNS CaFe Mg B Mn Cu Zn Co Mo Cl

pH and Nutrient Availability

Soil Fertility

Nutrient Movement

0 5 10 15 20 25 300

50

100

150

200

250

300

350

400

450N (pounds per acre)

raw1

raw2

raw3

raw4

syn1

syn2

Linear (syn2)

Sample Date

0 5 10 15 20 25 300

200

400

600

800

1000

1200

1400P (lbs per acre)

raw1 raw2

raw3 raw4

syn1 syn2

Samples Date

Soil Test

Organic Matter

• Wonderful

• Holds Water

• Improves Drainage

• Holds Nutrients

• Improves Tilth

Biological Properties of Soil

•Organic Matter Content

•Plants

•Animals

•Microbial Biomass

Life

Soil Life - Animals

• Earthworms

• Mites

• Nematodes

• Protozoa• Beetles• Termites

Soil Life - Microbes

• Bacteria

•Single Cell

• Millions per Gram

• 1,000,000,000,000,000 per Acre

• Fungi

•Long filaments (hyphae)

• Hundreds of Thousands per Gram

•100,000,000,000,000 per Acre

Roles of Bacteria and Fungi

• Organic Matter Decomposition

• Soil Stabilization

• Aeration

• Tilth

• Nitrogen Fixation

Mycorrhizae (Fungus – Root)

Mycorrhizae (Fungus – Root)

Organic Soil Fertilizers

• Options

• Buy

• Grow Your Own

Organic Guidelines

Producer shall manage crop nutrients and soil fertility through rotations, cover crops, and the application of plant and animal materials (manures).

Organic Guidelines

Producer shall manage plant and animal materials to maintain or improve soil organic matter content in a manner that does not contribute to contamination of crops, soil, or water by plant nutrients, pathogenic organisms, heavy metals, or residues of prohibited substances.

Compost

Phosphorus A producer may use

Colloidal, rock phosphate

Bone meal

Guano

Fish emulsion processing

Potassium

A producer may use

• Wood ashes

• Rock dusts (granite, feldspar, greensand)

• Sulfate of potash magnesia

• Natural potassium sulfate

• Fly ash

• Recycled potassium-rich organic matter.

Calcium

• Can Use

•Agricultural limestone

•Agricultural gypsum

• Do Not Use

•slaked or hydrated lime.

Nitrogen

A producer may use

•Green manures

•Legumes

•Compost

•Vegetable meals

•Animal by-products and fish emulsion.

Cover Crops and Green Manures

• Cover Crops

•Grown in Winter

• Green Manure Crops

•Grown in Summer

Litter, Manure, etc

• Smelly

• Ammonia

• NH3

April 14

Cover Crops

Rye

April 16

Rye or Wheat

Legumes

Legume - Definition

• a dry dehiscent one-celled fruit developed from a simple superior ovary and usually dehiscing into two valves with the seeds attached to the ventral suture

Legume - Definition

A pod, such as that of a pea or bean, that splits into two valves with the seeds attached to one edge of the valves.

Legumes

• Peas

• Beans

• Soybeans

• Purple Hull Peas

• Crimson Clover

• Sweet Clover

• Hairy Vetch

• Alfalfa

• Lespedezea

• Black Locust

• Honey Locust

• Kudzu

• Mesquite

• Redbuds

• Wisteria

Arrowleaf Clover

April 16

Hairy Vetch

April 16

Crimson Clover

April 16

Crimson Clover

Nitrogen is Nutrient that is Most Limiting to Plant Growth

Atmosphere is 78% Nitrogen

Legume – Bacteria Symbiosis• Captures Nitrogen from the Air

• Makes Nitrogen Available to Plant

• Bacteria Responsible

• Rhizobia (Rhizobium)

• Bradyrhizobium (Soybeans)

rhi·zo·bi·um

Rhizobium group and species

Legumes treated

Rhizobium leguminosarum biovar trifoli Crimson clover, Red clover, White clover

Rhizobium leguminosarum biovar phaseoli

Kidney beans, Snap beans, String beans, Wax beans

Rhizobium leguminosarum biovar viceae Austrian winter pea, Common vetch, Garden pea, Hairy vetch

Rhizobium sp. Crownvetch

Bradyrhizobium japonicum Soybeans

Bradyrhizobium sp. (Vigna) Common lespedeza, Cowpea, Peanut, Velvet bean

Sinorhizobium melilotiAlfalfa, Medic, Yellow or white sweet clover

Inoculum

• Use slurry

• Commercial Sticker

• Sugar-water solution

• Karo syrup solution

Precautions !!!!

• Inoculum is Alive (hopefully!)

• Inoculum can Die (unfortunately)

• Note Expiration Date

• Avoid Fertilizers, Chemicals, Chlorine

Precautions !!!!

• Refrigerate during Storage

• Keep temperature below 90 F

• Avoid High or Low pH

• Avoid Exposure to Sunlight

Summary (Plants and Microbes)

• Add organic matter

• Avoid compaction

• Timely irrigation

• Promote drainage

• Promote aeration

• Neutral pH

Crimson Clover

April 16

Crimson Clover

Organic Matter