Name______
Period______
Soils and Soilless Media Test
True/False
Indicate whether the statement is true or false.
____1.The forces of water and wind help to create soil.
____2.The largest soil particles are clay particles.
____3.The A horizon is usually darker than the layer under it.
____4.Subsoil contains the most organic matter.
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____5.Which horizon is called topsoil by most growers?
a. / O horizon / c. / A horizonb. / R horizon / d. / B horizon
____6.Geologically speaking, soil is defined as:
a. / A collection of natural bodies of the earth’s surface, in places modified or even made by man or earthy materials, containing living matter and supporting or capable of supporting plants out-of-doorsb. / the material that nourishes and supports growing plants, including rocks, water, snow, and even air—all of which are capable of supporting plant life
c. / the loose surface of the earth as distinguished from solid bedrock
d. / the collection of natural bodies occupying portions of the earth’s surface that support plants
____7.Which of these is a physical property of soil?
a. / composition / c. / bulk densityb. / Water-holding capacity / d. / all answers are correct
____8.The soil texture triangle may be used to determine the textural name of a soil by:
a. / measuring the percentage of sand, silt, and clay present in the soilb. / measuring the percentage of air and water in the soil
c. / visually comparing the soil sample to images of different types of soil on a chart
d. / weighing one cup of soil that has been completely dehydrated
____9.The soil profile refers to the arrangement and properties of the various soil layers including all BUT which of these?
a. / subsoil / c. / parent materialb. / organic material / d. / topsoil
____10.Sandy soil consists of _____.
a. / 30% clay / c. / equal parts silt, clay, and sandb. / less than 50% clay / d. / less than 20% silt and clay
____11._____ may be used to determine the name of a soil by mechanical analysis, actually measuring the percentages of sand, silt, and clay present in the soil.
a. / texture triangle / c. / triangulation analysisb. / textural analysis / d. / textile analysis
Completion
Complete each statement.
12.The term ______refers to the rock or other material in which the soil formed.
13.The ______is a vertical section through the soil extending into the unweathered parent material and exposing all the horizons.
14.The term ______refers to the amount of sand, silt, and clay in the soil.
15.Soils that are silty or loamy in nature are considered to have ______texture.
16.After soil has been saturated with water, one can observe a vertical, downward movement of water due to ______.
17.Ideal water-to-air ratio is ______air and ______water.
Matching
Match each of the particles below with the corresponding diameter limits.
a. / silt / d. / coarse sandb. / gravel / e. / clay
c. / fine sand
____18.above 2.00
____19..05–.002
____20.1.00–.50
____21..25–.10
____22.below .002
Match the following definitions with the terms below.
a. / dehydrated remains of acid bog plants used in shredded form for seedb. / very light, expanded material with neutral pH
c. / gray-white material of volcanic origin, usually used to improve aeration of the media
d. / partially decomposed vegetation that has been preserved underwater
____23.Perlite
____24.Sphagnum moss
____25.Peat moss
____26.Vermiculite
Short Answer
27.Identify the five factors in influencing soil formation.
28.Identify the four substances that make up soil.
29.This type of water is held in the small pore spaces of the soil.
- Name two advantages of soilless media.
Soils and Soilless Media Test
Answer Section
TRUE/FALSE
1. ANS:T
Heating and cooling or weathering, the forces of water and wind, all help to create soil. Decomposed plant and animal material also add to the makeup of soil.
PTS:1
2. ANS:F
Sand particles are the largest in size. Clay is the smallest particle.
PTS:1
3. ANS:T
The surface layer or topsoil is usually called the A horizon. It is usually brown in color, and often darker than the layer under it. It is darker because it is near the surface where there is a lot of organic matter from decaying plants.
PTS:1
4. ANS:FPTS:1
MULTIPLE CHOICE
5. ANS:C
The A horizon is called topsoil by most growers.
FeedbackA / The O horizon is an organic layer made of wholly or partially decayed plant and animal debris. It’s the A horizon that is called topsoil by most growers.
B / The R horizon is underlying hard bedrock, not topsoil.
C / Correct.
D / The B horizon is known as subsoil, not topsoil.
PTS:1
6. ANS:C
Geologically, soil is defined as the loose surface of the earth as distinguished from solid bedrock.
FeedbackA / This is the soil taxonomy definition of soil, not the geological definition.
B / This is the traditional definition of soil, not the geological definition.
C / Correct.
D / This is the definition of soil as a portion of the landscape.
PTS:1
7. ANS:D
The physical properties of soil are composition, texture, structure, bulk density, depth, color, and water-holding capacity.
FeedbackA / Water-holding capacity and bulk density are also physical properties of soil.
B / Composition and bulk density are also physical properties of soil.
C / Composition and water-holding capacity are also physical properties of soil.
D / Correct.
PTS:1
8. ANS:A
The soil texture triangle may be used to determine the textural name of a soil by mechanical analysis—actually measuring the percentage of sand, silt, and clay present in the soil. After the percentages of silt and clay are determined, these amounts are plotted on the soil triangle.
FeedbackA / Correct.
B / It measures the percentages of sand, silt, and clay, not air and water.
C / The soil texture triangle is used to determine the textural name of a soil by measuring the percentage of sand, silt, and clay in it, not by visual comparison.
D / The soil texture triangle is used to determine the textural name of a soil by measuring the percentage of sand, silt, and clay in it, not by weighing it.
PTS:1
9. ANS:B
Organic matter is what is left of decayed plants and animals, and is an important component of topsoil, but it is not a separate layer.
FeedbackA / Subsoil is one of the three soil layers.
B / Correct.
C / Parent material is the lowest of the three layers.
D / Topsoil is the top layer.
PTS:1
10.ANS:DPTS:1
11.ANS:APTS:1
COMPLETION
12.ANS:
parent material
Parent material refers to the rock or other material in which the soil formed. The parent material provides the original minerals from which the soil develops. The soil forms by weathering of these original minerals, and through additions of new material or losses of other material.
PTS:1
13.ANS:
soil profile
The soil profile is a vertical section through the soil extending into the unweathered parent material and exposing all the horizons. Each horizon in the profile differs in some physical or chemical way from the other horizons.
PTS:1
14.ANS:
soil texture
Soil texture refers to the amount of sand, silt, and clay in the soil.
PTS:1
15.ANS:
medium
Soils that are silty or loamy in nature have a medium texture. To the touch, they feel that they should be between fine and coarse texture.
PTS:1
16.ANS:
gravity
After the soil has been saturated with water, one can observe a vertical, downward movement of water due to gravity. The exact time depends on the soil type; the drainage of the gravitational water generally takes a little longer for clayey soils.
PTS:1
17.ANS:
50%, 50%
fifty percent, fifty percent
PTS:1
MATCHING
18.ANS:BPTS:1
19.ANS:APTS:1
20.ANS:DPTS:1
21.ANS:CPTS:1
22.ANS:EPTS:1
23.ANS:CPTS:1
24.ANS:APTS:1
25.ANS:BPTS:1
26.ANS:DPTS:1
SHORT ANSWER
27.ANS:
The five factors influencing soil formation include:
1. parent material
2. time
3. climate
4. organisms
5. topography
PTS:1
28.ANS:
The four substances that make up soil are:
1. small mineral particles
2. organic matter
3. water
4. air
PTS:1
29.ANS:
Capillary
PTS:1
30.ANS:
Name any two of the following: (1) mix is uniform in fertility, pH, and texture; (2) mix contains no diseases, insects, or weed seeds; (3) mix is lighter in weight and easier to handle; (4) mix has good moisture retention and drainage.
PTS:1