Lab #4 Soil Properties and Plant Growth

500-1,000 years

For 1 inch top soil to form

What are the three basic parts of the soil

Mineral Part-Organic Matter-Biotic Component

List the 10 macronutrients

Carbon C-Hydrogen H-Oxygen O-Nitrogen N-Phosphorus P-Potassium K-Calcium Ca-Magnesium Mg-Sulfur S-Sodium Na

List the 10 micronutrients

Iron Fe-Zinc Zn-Copper Cu-Boron B-Molybdenum Mo-Manganese Mg-Chlorine Cl-Cobalt Co-Vanadium V-Silicon Si

The mineral part of the soil comes from where

The weathering of the stony parent material

Organic matter comes from_______and_______when these decay it is called

-Dead plant and Animal plant

-Humus

What are the basic soil particles making up the mineral portion of the soil

Sano-Silt-Clay

Which soil particle is chemically most active

-Clay

What are the 2 components held in the soil pore space

Water and Air

What are large soil pores and small soil pores called

Large pores-Noncapillary pores/Small pores-Capillary pores

What are the 3 major functions that the soil serves for plants

1:Medium to anchor the roots

2:Reservoirto store and supply essential moisture to plants

3:Except for carbon C, hydrogen H, oxygen O, all of the plant’s essential chemical elements are supplied by the soil

What are the 3 essential elements that occur plentiful in nature

Carbon-Hydrogen-Oxygen

Which essential elements are referred to as the primary plant foods

Nitrogen-Phosphorus-Potassium

Which are referred to as secondary elements

Calcium-Magnesium-Sulfur

If micronutrients are applied to soils are they applied at the same relative amounts as macronutrients and why

NO, they are very rarely applied but if applied extreme caution must be exercised to avoid adding toxic qualities that would be toxic to the plant growth

In naturally fertile soil’s nitrogen comes from which basic soil part

Organic Matter

Define exchange capacity

-The soil’s capacity ro hold a positively charged atom or molecule e.g., Ca2+, NH4+

Which type of soil has the highest exchange capacity

Clay

Define soil reaction

-It is a measure of the degree of acidity or alkalinity of a given soil and is usually expressed in terms of pH

What is the purpose in liming a soil

To raise the pH of acid soils

Where is liming most common and why

In the Southeastern and Eastern U.S. due to more rainfall

What is considered neutral on the pH scale

7

Where would an alkaline soil appear on the pH scale or an acid soil

> 7

<6.6 or 7

What determines soil texture

The proportion of the 3 particle groups in a given soil

Which soil types hold relatively large amounts of water

Clay

Using the attached soil triangle give the soil class name for the listed soil textures

10-70-20 Silty Loam

80-10-10 Clay

30-60-10 Silty Clay Loam

40-20-40 Clay Loam

20-40-40 Loam

0-10-90 Sand

Define soil structure

How particles group together and form aggregates

___________tends to improve soil structure

Organic Matter

List 3 ways soil structure can be damaged

1:Excessive cultivation

2:Excessive traffic over a field

3:Working the soil when it is wet

The depth of the soil influences the area in which ________ may grow thus influencing the potential soil ______ reservoir and available ______

Roots

Water and Minerals

Define saturation as it pertains to plant soil water relationships

Saturation is the condition of a soil after an irrigation or heavy rain when addition water is added it either flows through the soil or runs off the surface

What is FC for a clay soil

4 inches for clay soil

When plants wilt and fail to recover until water is added the moisture remaining in the soil is its

Permanent Wilting Percentage or PWP

What is meant by available moisture as it pertains to plants

The moisture between FC and PWP is the moisture plants use