Soil Midterm

What features does a Typic Calciustalf likely contain?

An argillic horizon and pedogenic accumulation of calcium carbonate

What soil order commonly has a Bhs horizon?

Spodosols

Which describes a fragipan soil horizon?

Both Bx and Btx

What moisture regime is a Calcic Paleustoll found in?

Ustic

Which profile sequence most likely represents a Mollisol?

Ap-A-AB-Bw1-Bw2-Bw3

What lowercase letter goes with an A horizon that has been plowed?

p

What is the great group of a Vertic Argidurid?

Argidurids

What feature does the Guelph soil series contain?

Argillic horizon

What is the soil order of a Cumulic Hapludox?

Oxisols

How would you describe a natric horizon?

Btn

Which soil order includes desert soils?

Aridisols

What lowercase letter indicates carbonate accumulation that fizzes with acid?

k

What describes a mollic epipedon?

Thick, dark, high in organic matter, high base saturation

What diagnostic subsurface horizon shows limited pedogenesis?

Cambic

What formative element appears in an Entisol formed in a Michigan sand dune?

Psamm

How do you name a clay-enriched subsoil with clay films on ped faces?

Bt

Which soil order is probably the most intensely weathered?

Ultisols

What epipedon is thin, light-colored, low in organic matter, and nutrient-poor?

Ochric

What color rule indicates prolonged wetness in soil?

Chroma less than 2

What USDA soil separate is a 1-micrometer particle?

Clay

What is the texture class of 11 g clay, 33 g silt, and 4 g sand?

Silt loam

What is the bulk density of 32 g dry soil in 23 cm³?

1.4 g/cm³

What is the bulk density of 124.1 g dry soil in 98 cm³?

1.27 g/cm³

What particle density is usually assumed for soils?

2.65 g/cm³

What is porosity when particle density is 7.87 and bulk density is 2.42 g/cm³?

69.2%

What soil structure is typical of a healthy A horizon?

Granular

Which texture is finer: silty clay or sandy loam?

Silty clay

What is the water content when soil can be molded like putty?

Between the plastic limit and liquid limit

What soil structure has tall units with rounded tops, often encrusted in salts?

Columnar

What soil structure has peds with sharp corners and edges?

Angular blocky

What feature might an ochric epipedon lack in the A horizon?

Fine stratification

Which material does not appear on the soil texture triangle?

Gravel

What physical law describes settling velocity in hydrometer analysis?

Stokes' law

Can sieves effectively separate silt from clay?

No

What primarily determines particle settling rate?

Particle radius

How is 10YR 4/6 pronounced?

Ten Y-R four six

What happens when a submerged soil aggregate immediately disintegrates?

Slaking

What is the Munsell value of 7.5YR 3/2?

3

What are morphological rules for identifying hydric soils called?

Hydric Soil Indicators

What is water repellency after a burn called?

Hydrophobicity

Where does almost all energy on Earth come from?

The Sun

How should indoor plants be prepared for summer sunlight?

Harden them off gradually over days or weeks

What role does fire play in ecosystems?

All of the above

What is the warmest slope aspect in Michigan?

Southern

Which plant is sensitive to growing with wet feet?

Sugar beets

What is an iron- and manganese-cemented object with visible rings called?

Concretion

What charge does iron have after reduction?

+2

What does alpha-alpha-dipyridyl indicate in wetland soil?

Pink color indicating reduced iron

Where is the most highly reduced part of a Winogradsky column?

The bottom

Plants use oxygen and produce carbon dioxide.

True

How should you mulch a tree?

Apply a thin layer over the root zone, keeping mulch several inches from the trunk

What is reasonable room temperature in Celsius?

21°C

Plants use carbon dioxide and produce oxygen.

True

What causes Earth's seasons?

Earth's axial tilt as it orbits the Sun

How can you prevent overheating on a shale-covered slope?

Spread straw or another light-colored material over the surface

After iron reduction, what is the next preferred terminal electron acceptor under the stated conditions?

Sulfate sulfur

While iron minerals remain in anoxic soil, what substance may remain oxidized?

Sulfate