soil

Soils SOIL is a dynamic system of living and nonliving components. DIRT is soil out of place

Soil components Mineral Organic Water Air Living Organisms

Mineral components Derived from rock The nature of the soil depends on the kind of rock and the degree of weathering Mineral soil is quite permanent

Mineral components Texture- the name of a soil is based on the mineral components if soil is less than 20% organic, it is called a mineral soil. Particle size: –coarse SAND mm –SAND um (microns) –SILT um –CLAYless than 2um

The name of a soil is based on its mineral components.

Water

Soil structure How soil clumps or aggregates –Determines pore space –Aggregates are classified by shape Flat, prism-shaped, block-like, plate-like, and spheroid Spheroid is optimal but the clay in Duluth is plate- like

Physical forces that result in aggregation Freezing and thawing Wetting and drying Action of worms, and other organisms Root growth

Organic components Humus, litter, duff Plant, animal, bacterial, fungal remains Always disappearing due to decay % of organic matter depends on –Rate of accumulation –Rate of or resistance to decay –Climate Cold /dry = minimal decay Hot/ damp = fast decay

Importance of Organic material Holds available minerals and nutrients Increases water holding in sandy soil Increases drainage by aggregating clay Inhibits erosion

Sources of organic material for the garden Manure from farm animals ( composted) Green manure crops Sewage sludge compost

Soil Water

Capillary Water = available to plants Maximum Cap water = field capacity The amount of water available to plants is determined by: –Texture of the mineral component AND –% organic material

Water holding capacity = field capacity - wilt »SANDY SOILSILT/LOAM FIELD CAP % WILT AVAILABLE H2O Soil texture and % organic mater determines the amount of water available to plants

Soil Atmosphere High in CO2, low in O2 O2 necessary for cellular respiration in roots Aquatic plants have special adaptations

Soil Organisms Bacteria, Fungi, algae = 75% of the dry weight of organisms Worms = 12% dry weight Invertebrates = 13%

A –Leaching –Most plant growth –Humification B –Deposition –Less organics –N+K C. Parent material Horizons

Nutrients Macronutrients % dry weight of plant Ca.5% Mg.2% S.1% O45% H6% C45% N1.5% P.02% K1.0%

Nutrients Micronutrients.01% to.00001% % dry weight of plant Mo B Fe Cl Cu Zn Mn

C HOPKINS CAFÉ MIGHTY GOOD, BUT MANY MORE PREFER CLARA’S ZANY CUP

Nitrogen Fixation

Oats as a green manure crop

Soil fertilization Chemical N:P:K –comes from industry –Very concentrated –Easy to apply Organic –Comes from animals plants or rocks –Without a lot of processing –Low nutrient, heavy –Comes with a lot of organic material bulk

Fertilizer analysis is the % by weight of a nutrient N in the form of elemental Nitrogen P is Phosphorus as P 2 O 5 K is Potassium as K 2 O All commercial fertilizer must have N:P:K: on the bag.

analysis ratio NPK 3300Ammonium Nitrate1:0:0 212Sheep Manure2:1: Lawn Fertilizer5:1: Vegetable Fertilizer1:1:1 The ratio is important, grass needs lots of N, veggies will not produce if they get lots of N.

A soil test will tell you what your soil is lacking Go online or Call the ag extension office and get a soil test kit Follow the directions, send it in, and the results take about 2 weeks. Add the nutrients as listed on your test report Look at tables on pages 29s-31s

Changing pH of soil If soil is too acid Lime (agricultural) not Hydrated Organic ( Dolomitic Lime) If soil is too alkaline Sulfur Organic – Peat moss ( pH 4.5) Changing pH of water add baking sodaAdd an acid ( lemon juice or vinegar)

Changing soil texture To loosen clay –Add organic material to create aggregates to increase drainage –Add gypsum –Add sand –Work the soil when it is a the right moisture level not too wet or dry. Soil should not stick to the shovel, and a handful should break apart To make sand retain water –Add organic material –Add clay ( it can be bought as a powder in bags) –Add an organic mulch to the soil surface

If your soil is too wet because the water table is too high in spring Tiling is placing drain tile in the ground it should come out down hill. Raised beds

Mixing potting soil Soil in a pot needs to be mixed with different textures to allow air and water spaces Common horticultural soil mixes have Peat Vermiculite and Perlite added Soilless mixes have no actual loam added

Peat Is the most common organic soil component, it does not need to be pasteurized. Peat has some “politics”. An alternative is Coir

Vermiculite The ore is dried then flash heated to 1000 degrees F

Perlite/ Krum Perlite starts out as a volcanic glass and is heated to F and popped It is used as insulation and soil additive.

Fertilizer calculations 32s-33s You need to figure out how much of what fertilizer and how to apply it and when to apply How big is the area where fertilizer needs to be applied. According to the soil test result how many pounds of your chosen fertilizer do you need? Are you going to broadcast or side dress Or split the application spring and fall?

How to apply

Broadcast and till is quite common for a city garden. This happens just before transplant. Side dress or band is what happens when you feed mid season. The fertilizer does not touch the plants. Feeding trees usually happens as the buds swell in spring and depending on the tree thy can be foliar fed as fruit is developing.

Fertilize in two or more directions to get even coverage

Feeding Trees