AZ Soils Guide

Multiple Choice

A soil that is blackish in color probably contains a lot of:

• organic matter

• iron

• nickel

• copper

Multiple Choice

A soil that is reddish in color probably contains a lot of:

• salt

• silicon

• clay

• iron

Multiple Choice

Sandy soils have at least _____ percent sand particles.

• 40

• 50

• 60

• 70

Multiple Choice

Which of the soil particles is the largest?

• clay

• silt

• sand

• perlite

Multiple Choice

Which of these is not a soil particle?

• clay

• silt

• sand

• perlite

Multiple Choice

Water Holding Capacity is an important soil property in soil because:

• It is measure of the portion of water in the soil that is available to plants

• It is measure of all the water in a soil profile

• It is measure of water in the soil that is moved down by gravity

• It is measure of soil water after a heavy rain or full irrigation run

Multiple Choice

Water holding capacity is lowest in:

• Soils high in sand

• Soils high in loam

• Soils high in silt

• Soils high in clay

Multiple Choice

Clay soils have a smooth, velvety feel, particularly when moist.

• True

• False

Multiple Choice

Why is soil texture important?

• It determines how fast water drains through soil

• It determines how much water a soil can hold and make available to plants

• Both written responses

• Neither written responses

Multiple Choice

Loam

• When rubbed between the thumb and fingers, approximately equal influence of sand, silt and clay is felt. makes a weak ribbon (less than 2.5 cm long)

• Silt is the dominant particle in silt loam, which feels quite smooth or floury when rubbed between the thumb and fingers. Weak ribbon (less than 2.5 cm)

• Clay dominates, it is smooth when dry and slick/ sticky when wet. Silt and sand are usually present in noticeable amounts, but are over shadowed by clay. Medium ribbon (2.5 to 5 cm long)

• Varies from very fine loam to very coarse, Feels quite sandy or gritty, but contains some silt and a small amount of clay. The amount of silt and clay is sufficient to hold the soil together when moist. Weak ribbon (less than 2.5 cm long)

• Noticeable amounts of both silt and clay are present Makes a medium ribbon (2.5 to 5 cm long)

Multiple Choice

Silt Loam

• When rubbed between the thumb and fingers, approximately equal influence of sand, silt and clay is felt. makes a weak ribbon (less than 2.5 cm long)

• Silt is the dominant particle in silt loam, which feels quite smooth or floury when rubbed between the thumb and fingers. Weak ribbon (less than 2.5 cm)

• Clay dominates, it is smooth when dry and slick/ sticky when wet. Silt and sand are usually present in noticeable amounts, but are over shadowed by clay. Medium ribbon (2.5 to 5 cm long)

• Varies from very fine loam to very coarse, Feels quite sandy or gritty, but contains some silt and a small amount of clay. The amount of silt and clay is sufficient to hold the soil together when moist. Weak ribbon (less than 2.5 cm long)

• Noticeable amounts of both silt and clay are present Makes a medium ribbon (2.5 to 5 cm long)

Multiple Choice

Silt Clay Loam

• When rubbed between the thumb and fingers, approximately equal influence of sand, silt and clay is felt. makes a weak ribbon (less than 2.5 cm long)

• Silt is the dominant particle in silt loam, which feels quite smooth or floury when rubbed between the thumb and fingers. Weak ribbon (less than 2.5 cm)

• Clay dominates, it is smooth when dry and slick/ sticky when wet. Silt and sand are usually present in noticeable amounts, but are over shadowed by clay. Medium ribbon (2.5 to 5 cm long)

• Varies from very fine loam to very coarse, Feels quite sandy or gritty, but contains some silt and a small amount of clay. The amount of silt and clay is sufficient to hold the soil together when moist. Weak ribbon (less than 2.5 cm long)

• Noticeable amounts of both silt and clay are present Makes a medium ribbon (2.5 to 5 cm long)

Multiple Choice

Clay Loam

• When rubbed between the thumb and fingers, approximately equal influence of sand, silt and clay is felt. makes a weak ribbon (less than 2.5 cm long)

• Silt is the dominant particle in silt loam, which feels quite smooth or floury when rubbed between the thumb and fingers. Weak ribbon (less than 2.5 cm)

• Clay dominates, it is smooth when dry and slick/ sticky when wet. Silt and sand are usually present in noticeable amounts, but are over shadowed by clay. Medium ribbon (2.5 to 5 cm long)

• Varies from very fine loam to very coarse, Feels quite sandy or gritty, but contains some silt and a small amount of clay. The amount of silt and clay is sufficient to hold the soil together when moist. Weak ribbon (less than 2.5 cm long)

• Noticeable amounts of both silt and clay are present Makes a medium ribbon (2.5 to 5 cm long)

Multiple Choice

Total depth of the soil: very deep

• Greater than 60 inches

• 20-40 inches

• 10-20 inches

• 40-60 inches

• 0-10 inches

Multiple Choice

Total depth of the soil: deep

• Greater than 60 inches

• 20-40 inches

• 10-20 inches

• 40-60 inches

• 0-10 inches

Multiple Choice

Total depth of the soil: moderately deep

• Greater than 60 inches

• 20-40 inches

• 10-20 inches

• 40-60 inches

• 0-10 inches

Multiple Choice

Total depth of the soil: shallow

• Greater than 60 inches

• 20-40 inches

• 10-20 inches

• 40-60 inches

• 0-10 inches

Multiple Choice

Total depth of the soil: very shallow

• Greater than 60 inches

• 20-40 inches

• 10-20 inches

• 40-60 inches

• 0-10 inches

Multiple Choice

Slope: Nearly level

• 0-1%

• 1-3%

• 4-5%

• 5-8%

• 8-15%

Multiple Choice

Slope: Gently level

• 0-1%

• 1-3%

• 4-5%

• 5-8%

• 8-15%

Multiple Choice

Slope: Moderately level

• 0-1%

• 1-3%

• 4-5%

• 5-8%

• 8-15%

Multiple Choice

Slope: Strongly level

• 0-1%

• 1-3%

• 4-5%

• 5-8%

• 8-15%

Multiple Choice

Slope: Very strongly level

• 0-1%

• 1-3%

• 4-5%

• 5-8%

• 8-15%

Multiple Choice

Class 1

• suitable for cultivation over a long period of time

• subject to occasional over land flow, moderate risk of damage

• good for cultivated crops, has severe limitations

• clay; wildlife/ range; medium- moderately fine classes

• can be cultivated but has severe limitations

Multiple Choice

Class II

• suitable for cultivation over a long period of time

• subject to occasional over land flow, moderate risk of damage

• good for cultivated crops, has severe limitations

• clay; wildlife/ range; medium- moderately fine classes

• can be cultivated but has severe limitations

Multiple Choice

Class III

• suitable for cultivation over a long period of time

• subject to occasional over land flow, moderate risk of damage

• good for cultivated crops, has severe limitations

• clay; wildlife/ range; medium- moderately fine classes

• can be cultivated but has severe limitations

Multiple Choice

Class IV

• suitable for cultivation over a long period of time

• subject to occasional over land flow, moderate risk of damage

• good for cultivated crops, has severe limitations

• clay; wildlife/ range; medium- moderately fine classes

• can be cultivated but has severe limitations