SSC 200 Final Exam-Crouse
Residual soil acidity is that acidity remaining in the soil after limestone has been applied. (T/F)
False
Roots of most plants have difficulty growing through soil if the bulk density is greater than 1.0 Mg/m3. (T/F)
False
Roots of most plants have difficulty growing through soil if the bulk density is greater than 1.0 g/cm3. (T/F)
False
Routine soil testing on a regular basis allows landowners to monitor most changes in soil quality. (T/F)
False
Smectite and vermiculite are more prominent in extremely weathered soils than in soils where only modest weathering has occurred. (T/F)
False
The percent of total pore space in a soil can be calculated if only the particle density and the organic matter content are known. (T/F)
False
The plasticity index is used to determine soil texture. (T/F)
False
The soil horizon with the highest silicate clay accumulation is the _____ horizon. a. A b. E c. Bw d. Bt
Bt
The soil horizon with the highest silicate clay accumulation is the _____ horizon. a. A b. E c. Bw d. Bt
Bt
A soil developed in transported parent materials will likely have properties related to the properties of the rock below the C horizon. (T/F)
False
A soil with a high organic matter content will have a relatively higher bulk density. (T/F)
False
A tetrahedral sheet is characterized by a plane of aluminum atoms surrounded by oxygen and hydroxyl groups. (T/F)
False
A, B, C, and E horizons can be found in any true soil. (T/F)
False
All particles greater than 2.0 mm in diameter are collectively called sand. (T/F)
False
Ammonia volatilization is a process by which much needed nitrogen is added to the pool of plant- available nitrogen in soils. (T/F)
False
Hydraulic conductivity is commonly higher in soils on which conventional tillage systems have been used than where no-tillage systems have been followed. (T/F)
False
In a typical weathering sequence, rocks break down into secondary minerals which further undergo physical and chemical weathering to form primary minerals. (T/F)
False
In most B horizons one of the dominant processes of soil formation has been eluviation. (T/F)
False
Iron and manganese are commonly deficient in very acid soils. (T/F)
False
Micronutrient deficiencies are more likely to occur where manures, rather than inorganic chemical fertilizers, have been used to stimulate plant growth. (T/F)
False
Mulches and crop residues affect soil water by increasing evapotranspiration. (T/F)
False
Oxisols are the soil orders most commonly associated with the Midwestern prairie ecosystem. (T/F)
False
Polysaccharides produced by soil microbes and similar synthetic polymers applied to soils are largely responsible for the crusts that form when rain follows tillage. (T/F)
False
Practices that increase the soil organic matter level generally have favorable effects on the chemical and biological properties of soils, but have little or no effect on soil physical properties. (T/F)
False
Reduced forms of iron and manganese along with soil organic matter largely control the color of well-drained soils. (T/F)
False
Relative to core-aeration, spike-aeration is the preferred method of improving gaseous exchange between the soil and the atmosphere. (T/F)
False
Respiration by plant and animal cells along with photosynthesis increases soil carbon dioxide. (T/F)
True
Ridge-till systems show promise in the management of somewhat poorly drained soils of the Midwest. (T/F)
True
Soil air usually has a higher carbon dioxide content than the air in the atmosphere. (T/F)
True
Soil compaction has no effect on particle density. (T/F)
True
Soil microorganisms often compete with higher plants for mineral nutrients, such as nitrogen. (T/F)
True
The O horizons of a soil are dominantly organic horizons occurring above mineral horizons. (T/F)
True
The T values are the maximum losses of soil by erosion that can be tolerated without a reduction in the soil's long term productivity. (T/F)
True
The amount of exchangeable acidity is much smaller than the residual acidity. (T/F)
True
Soil occupies the ________ part of the regolith. a. lower b. younger c. upper d. Both B and C
Upper
Organic matter distribution in the soil is a significant criterion for differentiating epipedons. (T/F)
True
Organic matter is important for the stabilization of soil structure. (T/F)
True
Practices that tend to increase the amount of organic matter in soils would be expected to reduce the global greenhouse effect. (T/F)
True
A soil at field capacity has what percent water in the macropores? a. 0% b. 25% c. 100% d. Cannot answer this question with the information provided.
0%
A pure clay crystal of kaolinite contains one octahedral layer and one tetrahedral layer. Which of these descriptions best describes the individual tetrahedrons that form the tetrahedral layer? a. 1 aluminum and 6 oxygens b. 6 aluminums and 1 oxygen c. 1 silicon and 4 oxygens d. 4 silicons and 1 oxygen
1 silicon and 4 Oxygens
A soil with a loam textural class might contain _____ a. 20% clay b. 20% silt c. 20% sand d. Not enough information is provided
20% clay
A soil with a clay textural class might contain _____ a. 35% clay b. 45% silt c. 40% sand d. Not enough information is provided
40% sand
The evapotranspiration (ET) from a pine forest was found to be 50 cm during a growing season. If the evaporation from the soil surface during this period of time was 5 cm, what is the level of loss from leaf surfaces? a. 45 cm b. 50.0 cm c. 55 cm d. Impossible to calculate from the data given e. 10 cm
45 cm
In a load of 10 cubic meters of topsoil, approximately how cubic meters of the volume would be solid material?
5
"Topsoil" is generally equivalent to which soil horizon? a. A b. B c. C d. R
A
The _____ horizon is topmost mineral horizon. a. O b. A c. E d. B
A
In many soil profiles, the subsoil is high in clay, but is also quite permeable, allowing water to percolate relatively well. Why? a. A blocky or sub-angular blocky structure may be well developed. b. Clay generally promotes free water movement. c. The water table may be present in the subsoil. d. The subsoil may have an organic texture.
A blocky or sub-angular blocky structure may be well developed.
You would be most apt to look in _____ if you wanted to find a soil where physical weathering dominated over chemical weathering. a. a desert region of Arizona b. the foothills of the Georgia mountains c. a coastal plain area of North Carolina d. a humid region in Brazil
A desert region of Arizona
Clay minerals are more chemically active than quartz sands because they have _____. Select one: a. Fewer negative charges b. More silicon c. A greater surface area d. All of the above e. None of the above
A greater surface area
Given three soil profile descriptions, A-B-C; A-C; A-E-B, and A-Bw-C rank the soils in order of most mature to least mature. a. A-E-B → A-C → A-Bw-C → A-B-C b. A-C → A-Bw-C → A-B-C → A-E-B c. A-Bw-C → A-C → A-E-B → A-B-C d. A-E-B → A-B-C → A-Bw-C → A-C
A-E-B → A-B-C → A-Bw-C → A-C
Given three soil profile descriptions, A-B-C; A-C; A-E-B, and A-Bw-C rank the soils in order of most mature to least mature. a. A-E-B → A-C → A-Bw-C → A-B-C b. A-C → A-Bw-C → A-B-C → A-E-B c. A-Bw-C → A-C → A-E-B → A-B-C d. A-E-B → A-B-C → A-Bw-C → A-C
A-E-B → A-B-C → A-Bw-C → A-C
Which of the following soil horizon sequences would be associated with the most mature soil profile? a. A-E-Bt-C b. Ap-Bw-C-R c. A1-A2-Bg-Cg d. A-Bt1-Bt2-BC-C-R
A-E-Bt-C
pH is a measure of _____ acidity. a. total b. reserve c. exchangeable d. active
Active
Deposition of colluvial parent material is an example of which of the soil forming processes? a. Additions b. Eluviation c. Translocations d. Chemical Weathering
Additions
The atmosphere is made up of a. water b. plants and animals c. air d. rock
Air
Soils from which order would exhibit properties dominated by chemical weathering of minerals? a. Histosol b. Alfisol c. Gelisol d. Aridisol
Alfisol
Soils from which order would exhibit properties dominated by chemical weathering of minerals? a. Histosol b. Alfisol c. Gelisol d. Aridisol
Alfisol
Select the appropriate soil order: A true B horizon is present. The subsoil has a base saturation greater than 35%. a. Alfisols b. Inceptisols c. Oxisols d. Ultisols
Alfisols
Select the appropriate soil order: A true B horizon is present. The subsoil has a base saturation greater than 35%. a. Inceptisols b. Oxisols c. Alfisols d. Ultisols
Alfisols
Traveling from a cool, wet climate to a warm, wet climate one would likely leave ____________ and encounter _____________. a. Aridisols, Oxisols b. Alfisols, Ultisols c. Ultisols, Mollisols d. Mollisols, Aridisols
Alfisols, Ultisols
Traveling from a cool, wet climate to a warm, wet climate one would likely leave ____________ and encounter _____________. a. Aridisols, Oxisols b. Alfisols, Ultisols c. Ultisols, Mollisols d. Mollisols, Aridisols
Alfisols, Ultisols
Infiltration of precipitation is affected by _____. a. Slope b. Amount and type of vegetation c. Soil type d. All of the above
All of the above
Organic parent materials accumulate under which of the following conditions? a. Restricted aeration b. Cold & damp climates c. Water-logged soil conditions d. All of the above e. None of the above
All of the above
Organic parent materials accumulate under which of the following conditions? a. Restricted aeration b. Cold & damp climates c. Water-logged soil conditions d. All of the above e. None of the above
All of the above
Structure develops as the result of ____. a. Wetting and drying cycles b. Burrowing of macro-organisms c. Growth of plant roots d. All of the above
All of the above
The sulfur dioxide in the atmosphere ________. a. comes from fires such as fossil fuel burning, volcanoes and forest fires b. can be an important source of sulfur nutrition for plants c. is a major contributor to "acid rain" d. all of the above e. none of the above
All of the above
Which of the following increases soil acidity. a. Leaching of basic cations b. Application of ammonium sources of nitrogen fertilizers c. Weathering of clay minerals that release aluminum d. All of the above
All of the above
Which of the following is a greenhouse gas contributed to the atmosphere by soils? a. methane b. carbon dioxide c. nitrous oxides d. all of the above e. none of the above
All of the above
On very acid soils, a chemical problem that can reduce plant growth is _____. a. aluminum toxicity b. iron deficiency c. nitrate poisoning d. calcium toxicity
Aluminium toxicity
Assuming concentrations within the soil solution are the same, which of these cations would be most difficult to replace in the cation exchange system? a. Aluminum b. Chloride c. Sodium d. Potassium
Aluminum
What ion is probably most influential in causing very acid soil pH values? a. Aluminum b. Calcium c. Magnesium d. Sodium
Aluminum
Which ion hydrolyzes water molecules and causes some very low soil pH values. _____. a. Calcium b. Magnesium c. Aluminum d. Potassium
Aluminum
Which of these processes represent a loss of nitrogen from the soil nitrogen cycle? a. Ammonia Volatilzation b. Immobilization c. Mineralization d. Nitrification
Ammonia Volatilzation
Before plants can absorb nitrate-nitrogen that originated from residue of a previous crop, the following processes must have occurred: (Note: processes must be in correct sequence.) a. N-fixation, denitrification, b. ammonification, nitrification c. nitrification, denitrification d. mineralization, immobilization
Ammonification, nitrification
Alcohols, methane and organic acids of various kinds often accumulate as a result of ________ decomposition of residues in soil a. nitrogen-limited b. fungal c. acidic d. anaerobic e. abiotic
Anaerobic
Select the appropriate soil order: Soils of volcanic origin. a. Andisols b. Aridisols c. Entisols d. Inceptisols
Andisols
Select the appropriate soil order: Soils of volcanic origin. a. Andisols b. Aridisols c. Entisols d. Inceptisols
Andisols
Which of the following soil horizon sequences would be associated with the least mature soil profile? a. A1-A2-Bg-Cg b. A-E-Bt-C c. A-Bt1-Bt2-BC-C-R d. Ap-Bw-C-R
Ap-Bw-C-R
Soils from which order would exhibit properties dominated by physical weathering? a. Alfisol b. Aridisol c. Uultisol Incorrect d. Oxisol
Aridisol
Residual parent materials would most likely be found _____. a. on a stream terrace b. in a peat-land c. at the base of a steep hill d. on a glacial lake plain e. at the summit of a steep hill
At the summit of a steep hill
In which of the following horizons has the process of illuviation most likely occurred? a. A horizon b. E horizon c. C horizon d. O horizon e. B horizon
B horizon
Oxidation or reduction of inorganic soil constituents such as iron and sulfur is carried out by members of which group(s) of microorganisms a. bacteria b. fungi c. actinomycetes d. A and C e. all of the above
Bacteria
Of the horizons listed below, organic matter accumulation is most pronounced in the ______. a.E b. Bw c. Bh d.C
Bh
The A horizon is noted for its high degree of _____. a. clay accumulation b. illuviation c. biological activity d. calcium carbonate accumulation
Biological Activity
The A horizon is noted for its high degree of _____. a. clay accumulation b. illuviation c. biological activity d. calcium carbonate accumulation
Biological Activity
A soil that is well aerated in a cold climate with high organic matter content and low clay would most likely be what color? a. Black b. Grey c. Red d. White
Black
Match soil colors and their cause or implication. Well aerated, warm climate, high organic matter, low clay. a. White b. Black c. Red d. Grey
Black
What property would be most useful in determining how fast a soil will exchange oxygen for carbon dioxide in the plant root zone? a. Particle density b. Texture c. Bulk density d. Plasticity index
Bulk Density
Parent material is generally equivalent to which soil horizon? a. A b. B c. C d. O
C
Parent material is generally equivalent to which soil horizon? a. A b. B c. C d. O
C
Which suborder has the lowest soil moisture levels? a. Udept b. Ustox c. Aquent d. Cambid
Cambid
Which suborder has the lowest soil moisture levels? a. Udept b. Ustox c. Aquent d. Cambid
Cambid
In a tropical rain forest, microbial decomposition of soil residues is least important in controlling the plant-availability of the following nutrient? a. Carbon b. Phosphorus c. Nitrogen d. Sulfur
Carbon
n soil science, CEC is an abbreviation for _____. a. Carbonated Electrical Circuits b. Cationic Eluviation Center c. Cation Exchange Capacity d. Calcium Exchange Component
Cation Exchange Capacity
Which ion is most weakly attracted to soil colloids? a. Aluminum b. Chloride c. Sodium d. Potassium
Chloride
A loamy sand, sandy loam, loam and silt loam could contain the same percentage of _____ size particles. a. silt b. loam c. sand d. clay
Clay
A sticky, putty-like feel indicates a high percentage of which soil separate? a. silt b. humus c. sand d. clay e. none of the above
Clay
Colloidal properties are exhibited by the ________ fraction of soils. a. gravel b. sand c. clay d. silt
Clay
Given equal volumes of soil, the total particle surface area would be the greatest in a _____. a. silt loam b. sandy clay loam c. loam d. clay
Clay
In texture by feel methods, this component accounts for longer ribbon formation. a. Sand b. Silt c. Clay
Clay
Which type of parent material would you find as the result of gravity transportation? a. Glacial till b. Colluvium c. Alluvium d. Loess
Colluvium
Which type of parent material would you find as the result of gravity transportation? a. Glacial till b. Colluvium c. Alluvium d. Loess
Colluvium
Which type of structure is typically found in sodium-rich sub-surface horizons? a. sub-angular blocky b. granular c. columnar d. platy e. prismatic
Columnar
_____ structure is typically found in sodium-rich sub- surface horizons. a. Columnar b. Platy c. Sub-angular blocky d. Prismatic
Columnar
There are six soil master horizons, each designated by a different capital letter. The O horizon is a highly organic layer that forms at the soil surface, e.g.,under forest vegetation. The R horizon is the bedrock horizon. Which of the following is not one of the other four master horizons? a. A b. E c. D d. B e. C
D
Soils classified as Inceptisols have the least well-developed profiles of those in any order in the Soil Taxonomy system. a. True Incorrect b. False, made true by changing Inceptisol to Oxisol c. False, made true by changing Inceptisol to Alfisol d. Dang it! It is just false!
Dang it! It is just false!
When bulk density ____, the porosity _____. a. Increases, Decreases b. Decreases, Decreases c. Decreases, Increases d. Has no effect
Decreases, Increases
Which of the following processes does not increase the amount of nitrogen available to plants? a. Denitrification b. Mineralization c. Symbiotic N-fixation d. N fertilization
Denitrification
Soil texture is _____. a. Greatly affected by organic matter accumulation b. Altered easily by plowing a soil c. Determined by the relative distribution of sand, silt and clay d. None of the above
Determined by the relative distribution of sand, silt and clay
The horizon of maximum loss by leaching would be? a. R b. E c. C d. B e. A
E
Which horizon of a mature soil profile would you expect to find light colored and leached of clay? a. O b. A c. C d. B e. E
E
Which horizon of a mature soil profile would you expect to find light colored and leached of clay? a.O b.A c.E d.B
E
_____ is not considered one of the five major factors influencing soil formation. a. Elemental Valence state b. Climate c. Native parent materials d. Topography e. Living organisms
Elemental Valence state
A soil horizon sequence of A-C-R would be characteristic of which soil order? a. Alfisol b. Entisol c. Oxisol d. Ultisol
Entisol
A soil horizon sequence of A-C-R would be characteristic of which soil order? a. Alfisol b. Entisol c. Oxisol d. Ultisol
Entisol
Select the appropriate soil order: The "youngest" mineral soils that have no B horizon. a. Ultisols b. Entisols c. Inceptisols d. Alfisols
Entisols
Which processes are responsible for the transformation of igneous rock to sedimentary rock? a. Melting and Recrystallization b. Erosion, Deposition and Lithification c. Heat d. Erosion and Cooling
Erosion, Deposition and Lithification
The "Ac" value is an estimate of a. Active Acidity b. Exchangeable Acidity c. Ammonium Concentration d. Anion Content
Exchangeable Acidity
In a high elevation, cold desert, which weathering processes would dominate? a. Leaching and precipitation of secondary minerals b. Chemical weathering c. Exfoliation and mechanical processes d. Acid dissolution and lithification
Exfoliation and mechanical processes
A 1:5,000 soil survey covers a larger area with less detail than a 1:1,000,000 soil survey. (T/F)
False
Aridisols generally contain more organic matter than Mollisols. (T/F)
False
Capillary movement is made possible by the processes of cohesion, and has little to do with adhesion. (T/F)
False
Compared to sands, clays will have a relatively higher bulk density. (T/F)
False
Denitirification is the aerobic process by which wetlands remove nitrogen from groundwater. (T/F)
False
Epipedons are diagnostic subsurface horizons that are one of the primary means of classifying soils in the United States. (T/F)
False
Evapotranspiration includes vapor losses from the leaves of plants but not the soil surface. (T/F)
False
Examples genetic horizons include kandic, spodic, ochric, mollic and oxic. (T/F)
False
Examples of diagnostic horizons include A, B, C & E. (T/F)
False
For agricultural use in a given region, a soil with an ochric epipedon could generally be expected to be more productive than one with a mollic epipedon. (T/F)
False
Forests in decline because of acid deposition can often be brought back to high productivity with just a few applications of nitrogen fertilizer. (T/F)
False
Forests would typically have more organic accumulation than grasslands. (T/F)
False
Soil, like concrete and steel, is a standard construction material. Its properties are well characterized and predictable so that standard building foundation designs can be used uniformly at all building sites of a given topography. (T/F)
False
Soils can recycle organic compounds, but not inorganic elements. (T/F)
False
Soils classified as Inceptisols have the least well developed profiles of those in any order in the Soil Taxonomy system. (T/F)
False
Structure refers to the sizes of the individual particles that make up the soil minerals. (T/F)
False
Subsoiling is a primitive deep tillage technique that results in extremely high subsoil bulk density. (T/F)
False
The B horizon is the zone where you would expect maximum elluviation. (T/F)
False
The C horizons are generally more completely weathered than the other horizons. (T/F)
False
The ammonium form of N readily leaches from NC soils? (T/F)
False
The amount of active acidity is much larger than the exchangeable acidity. (T/F)
False
The amount of limestone required to increase the pH from 5 to 7 would be higher for an Oxisol than for an Alfisol. (T/F)
False
The lower the cation exchange capacity of a soil, the greater is its pH buffer capacity. (T/F)
False
The lower the cation exchange capacity of a soil, the higher is its buffer capacity. (T/F)
False
The terms "ammonium fixation" and "biological nitrogen fixation" refer to the same soil process. (T/F)
False
There is a net movement of clouds from land areas to the ocean areas in the hydrologic cycle. (T/F)
False
Till and outwash are both examples of parent materials readily found in North Carolina (T/F)
False
Weathering of rocks usually is most intense in the center of a rock fragment, and gradually decreases toward the outside. (T/F)
False
While many organisms depend on the soil for nutrients and water, only a few very specialized organisms live in the soil itself. (T/F)
False
A mollic epipedon is an example of a diagnostic subsurface horizon used in the USDA soil taxonomic system? a. True b. False, made true by changing Mollic to Umbric. c. False, made true by changing subsurface to surface. d. None of the answers are correct.
False, made true by changing subsurface to surface.
A mollic epipedon is an example of a diagnostic subsurface horizon used in the USDA soil taxonomic system? a. True b. False, made true by changing Mollic to Umbric. c. False, made true by changing subsurface to surface. d. None of the answers are correct.
False, made true by changing subsurface to surface.
The cation exchange capacity of humus is not affected by soil pH. a. False, the CEC of humus is entirely dependent on pH b. False, the CEC of humus is partially a function of pH and mostly a function of isomorphic substitution c. False, the CEC of humus is mostly a function of pH and partially a function isomorphic substitution d. True
False, the CEC of humus is entirely dependent on pH
Which micronutrient element is found in the greatest quantity in most soils? a. Mn b. Zn c. Fe d. Cu e. B
Fe
The White Store Series is a Fine, Mixed, Thermic Vertic Hapludalfs. What is the Family? a. Hapludalf b. Udalf c. Fine, Mixed Thermic d. Vertic Hapludalf
Fine, Mixed Thermic
You are working with a soil colloid known to have a reasonably high potassium level, a cation exchange capacity of about 20 cmolc/kg of clay and little tendency to swell when wetted. Which of the following is it most apt to be the dominant clay mineral in this soil? a. kaolinite b. vermiculite c. fine-grained mica d. smectite e. humus
Fine-grained mica
Select the one that doesn't go with the other three: a. Sand b. Silt c. Clay d. Granular
Granular
Which soil structure type would you expect to find in an A horizon of a soil formed in a humid environment? a. Platy b. Granular c. Blocky d. Columnar
Granular
Which type of soil structure is typically found in surface soil (A horizons)? a. granular b. columnar c. sub-angular blocky d. platy e. prismatic
Granular
The _____ method of estimating soil water levels gives a direct measurement of water content? a. gypsum block b. time domain reflectometry (TDR) c. gravimetric determination d. tensiometer
Gravimetric determination
Pesticides, excess plant nutrients and waste chemicals most likely to move through soils in the _____ water. a. capillary b. gravitational c. hygroscopic d. micropore
Gravitational
Compared to silt, clay-sized soil particles are characterized by ________. a. a greater attraction for water b. less tendency to form hard clods when dry c. less capacity to hold nutrients in plant-available forms d. greater proportion of primary minerals
Greater attraction for water
In acid soils the principal chemical form of phosphorus available for plant uptake is _____. a. H2PO4- b. P3+ c. CaPO42- d. PO43-
H2PO4-
Soil zones in which severe compaction has occurred will affect plant growth because of all of the following except _____. a. high soil strength b. high bulk density c. high oxygen levels d. high CO2 levels
High oxygen levels
The total phosphorus lost from an agricultural field is most closely correlated with _____. a. high soil cation exchange capacity b. high soil erosion c. low soil cation exchange capacity d. low slopes and low erosion
High soil erosion
Which of these soil properties doesn't fit with the other three? a. High sand content b. High permeability c. High surface area d. High macropore proportion
High surface area
A soil with a bulk density equal to 0.35 g/cm3 is most likely what type of soil? a. Ultisol b. Vertisol c. Histosol d. Aridisol
Histosol
If the soils are to be used for crop production, for which soil order would land drainage be most critical? a. Mollisols b. Aridisols c. Oxisols d. Inceptisols e. Histosols
Histosols
Select the appropriate soil order: Organic soils that are not frozen. a. Mollisols b. Spodosols c. Gelisols d. Histosols
Histosols
Soil age can best be determined by which factor? a. Parent material b. Surface color c. Horizonation d. Topography
Horizonation
The layers of contrasting material found when one digs a hole in the ground are called ________. a. pseudoliths b. pedons c. soil structure d. horizons e. regoliths
Horizons
The layers of contrasting material found when one digs a hole in the ground are called ________. a. regoliths b. pedons c. pseudoliths d. horizons e. soil structure
Horizons
All of the following are essential elements needed for a plant to complete its life cycle. Which one is considered a Structural Element? a. Sulfur b. Hydrogen c. Manganese d. Nitrogen
Hydrogen
All of the following are essential elements needed for a plant to complete its life cycle. Which one is considered a Structural Element? a. Sulfur b. Nitrogen c. Hydrogen d. Manganese
Hydrogen
Which of the following term/horizon combinations describes the zone of maximum clay accumulation in soils of humid regions? a. Illuvial, B horizon b. Eluvial, B horizon c. Illuvial, E horizon d. Illuvial, A horizon e. Eluvial, A horizon
Illuvial, B horizon
The biological conversion of the ammonium form of nitrogen into an unavailable form is _____. a. ammonification b. immobilization c. nitrification d. mineralization
Immobilization
Active soil pH describes the concentration of hydrogen ions found _____. a. on clay mineral exchange sites b. on organic colloid exchange sites c. embedded in the clay crystalline lattice d. in the soil solution
In the solution
Select the appropriate soil order: Soil profile is starting to show signs of horizonation. There is evidence of a weak B horizon. a. Entisol b. Inceptisols c. Oxisols d. Ultisols
Inceptisols
Select the appropriate soil order: Soil profile is starting to show signs of horizonation. There is evidence of a weak B horizon. a. Entisol b. Inceptisols c. Oxisols d. Ultisols
Inceptisols
Yellow colors in subsurface horizons are caused by _____ oxides in the soil. a. Aluminum b. Calcium c. Iron d. Manganese
Iron
In explaining erosion processes to a friend, which of the following would you say about accelerated erosion? a. It involves a much less rapid process than geological erosion. b. It is greatly enhanced by the splash effect of raindrops impacting bare soil. c. It removes more nitrogen from the surface soil than calcium. d. It is increasing in intensity in the United States, especially in the past 10 years. e. It refers to sediment carried by water flowing at ever greater velocity.
It is greatly enhanced by the splash effect of raindrops impacting bare soil.
Which of these properties about a tillage pan is false? a. Has a high ratio of micropores to macropores. b. It is a zone of high bulk density. c. It is permanent and cannot be corrected. d. It restricts root, air, and water progress.
It is permanent and cannot be corrected.
Which of the following statements is correct? a. Nutrient cycling in forested areas contributes little to soil formation. b. Limestone parent materials enhance the process of acidification. c. Calcium carbonate accumulation is more prominent in humid than in arid regions. d. Lacustrine parent materials have been subject to weathering for shorter periods of time than residual parent materials nearby. e. Soils on hillsides tend to be deeper than those on level lands.
Lacustrine parent materials have been subject to weathering for shorter periods of time than residual parent materials nearby.
Biomass consists of ________. a. identifiable biomolecules b. living organisms and cells c. dead tissues and wastes d. polymerized, non-identifiable molecules e. all of the above
Living organisms and cells
Which of the following is a deep organic soil? a. Sandy, Siliceous, Thermic Aeric Alaquods b. Loamy, mixed, dysic, thermic Terric Haplosaprists c. Coarse-loamy, Siliceous, Active, Acid, Thermic Cumulic Humaquepts d. Coarse-loamy, Mixed, Superactive, Nonacid, Thermic Typic Sulfaquents
Loamy, mixed, dysic, thermic Terric Haplosaprists
_____ is a parent material that would show evidence of sorting actions due to wind? a. Loess b. Colluvium c. Alluvium d. Till
Loess
______ is not considered one of the processes of soil formation. a. Additions b. Loessification c. Transformations d. Translocation
Loessification
______ is not considered one of the processes of soil formation. a. Additions b. Loessification c. Transformations d. Translocation
Loessification
All of the following are essential elements needed for a plant to complete its life cycle. Which one is considered a Micronutrient? a. Sulfur b. Calcium c. Manganese d. Nitrogen
Manganese
Select the appropriate epipedon: A mineral horizon that is very black in color due to its high organic matter content where the soil developed from volcanic ash. a. Mollic b. Umbric c. Melanic d. Histic e. Folistic
Melanic
Unavailable water is stored in _____. a. Macropores b. Mesopores c. Micropores d. All pores
Micropores
The process of _____ releases plant-available nitrogen as the result of the breakdown of nitrogen- rich organic compounds. a. denitrification b. mineralization c. symbiosis d. volatilization
Mineralization
The process of _____ releases plant-available nitrogen as the result of the breakdown of nitrogen-rich organic a. denitrification b. volatilization c. symbiosis d. mineralization
Mineralization
Which mineral colloid has the largest cation exchange capacity? a. Humus b. Montmorillonite, a 2:1 clay c. Kaolinte, a 1:1 clay d. Goethite, an iron oxide
Montmorillonite, a 2:1 clay
Which nutrient form is involved in reactions that acidify soil? a. K+ b. H2PO4- c. NH4+ d. Ca2+
NH4+
The very high pH levels found in some arid region soils are most likely due to high levels of exchangeable ________. a. Al(OH)2+ b. Al3+ c. Ca2+ d. Na+ e. Mg2+
Na+
Which of the following is an epipedon? a. Umbric b. Kandic c. Cambic d. Spodic
Umbric
In the United States, the government lead agency for most soil survey work is the _____. a. Agency for Soil Resource Inventory b. Department of the Interior c. National Bureau of Soil Survey d. Natural Resources Conservation Service e. Department of Land Reclamation
Natural Resources Conservation Service
Under which of the following conditions would you favor a finely ground dolomitic limestone as your choice among liming materials? a. Need for a rapid reaction with the soil b. Need to provide magnesium in addition to calcium c. Need for a material with a low shipping cost d. Need to obtain a high soil pH
Need to provide magnesium in addition to calcium
Which of these common plant nutrients would not be found bound as a cation to the surface of a clay mineral? a. Nitrate-nitrogen b. Potassium c. Calcium d. Magnesium
Nitrate-nitrogen
Conversion of the cationic form of soil nitrogen to the anionic form is _____. a. denitrification b. immobilization c. nitrification d. mineralization
Nitrification
Which process in the nitrogen cycle converts nitrogen into its most polluting form? a. Denitrification b. Mineralization c. Nitrification d. Immobilization
Nitrification
Nitrification is a two-step process with nitrite (NO2-) being formed in step one and then nitrite being oxidized to nitrate (NO3-) in step 2. Which bacteria are responsible for step 2? a. Nitrobacter b. Nitrosomonas
Nitrobater
Over the length of a growing season, which macronutrient would move furthest from a fertilizer pellet placed in the root zone? a. Nitrogen b. Phosphorus c. Potassium d. Chlorine
Nitrogen
Nitrification is a two-step process with nitrite (NO2-) being formed in step one and then nitrite being oxidized to nitrate (NO3-) in step 2. Which bacteria are responsible for step 1? a. Nitrobacter b. Nitrosomonas
Nitrosomonas
Which horizon would always be present in a Histosol? a. O b. B c. E d. R
O
Organic matter accumulation is most pronounced in the ________. a. C horizon b. A horizon c. B horizon d. O horizon e. E horizon
O horizon
In which of the following epipedons is the organic matter level generally lowest? a. ochric b. histic c. mollic d. melanic e. umbric
Ochric
_____ is not one of the five major factors of soil formation. a. Olluviation b. Time c. Topography d. Parent material e. Biological activity
Olluviation
A mollic diagnostic horizon would be noted for its high degree of ______. a. iron and aluminum accumulation b. clay content c. eluviation d. organic matter accumulation
Organic matter accumulation
Which formula best describes bulk density? a. Oven Dry Weight (g) /Volume of Soil (cm3) b. Oven Dry Weight (g) /Volume of Pores (cm3) c. Oven Dry Weight (g) /Volume of Particles (cm3) d. 1 + Particle Density
Oven Dry Weight (g) /Volume of Soil (cm3)
Which of the following is not an epipedon? a. Mollic b. Ochric c. Oxic d. Histic
Oxic
Which of the following is not an epipedon? a. Mollic b. Ochric c. Oxic d. Histic
Oxic
Which of the following subsurface diagnostic horizons would you expect to find in a highly weathered soil of the humid tropics? a. oxic b. natric c. cambic d. salic e. spodic
Oxic
Soils in which order would be dominated by minerals that are the most resistant to weathering? a. Spodosol b. Aridisol c. Oxisol d. Histosol
Oxisol
The nutrient most often limiting the growth of aquatic plants and algae in unpolluted fresh water lakes is ____. Addition of the element can often result in algal blooms. a. Ca b. K c. S d. P
P
Given the same length of time, which macronutrient diffuses in a soil the shortest distance relative to the other macronutrients? a. Chloride b. Nitrogen c. Phosphorus d. Potassium
Phosphorus
Which nutrient's plant availability is most closely governed by soil pH? a. Sulfur b. Phosphorus c. Potassium d. Carbon
Phosphorus
Select the one that doesn't go with the other three. a. Blocky b. Plasticity c. Columnar d. Prismatic
Plasticity
Select the one that doesn't go with the other three: a. Blocky b. Columnar c. Plasticity d. Prismatic
Plasticity
Select the appropriate structure: Thin, flat layers of soil that lie horizontally. Usually found in compacted soil. Not ideal for plant growth. a. Columnar b. Platy c. Blocky d. Granular
Platy
The ability of a soil to store water, that would later be available for plant growth, could be most accurately judged from knowing which characteristic? a. Soil texture b. Pore size distribution c. Bulk density d. Particle density
Pore size distribution
Continuous cultivation and soil compaction tend to reduce the amount of _____ in the soil. a. porespace b. clay c. minerals d. sand
Porespace
Practices that add organic matter and reduce tillage can be expected to most significantly increase the _____ in a soil. a. bulk density b. fineness of texture c. porosity d. sand content
Porosity
All of the following are essential elements needed for a plant to complete its life cycle. Which one is considered a Primary Macronutrient? a. Sulfur b. Hydrogen c. Manganese d. Potassium
Potassium
Select the appropriate structure: Vertical orientation. Can be found in the subsoils in humid regions. Lacks the salt "cap" typical of a similarly shaped unit of structure. Not ideal for plant growth. a. Blocky b. Prismatic c. Single grained d. Columnar
Prismatic
Which is not included in the epipedon? a. A horizon b. part of the B horizon (if significantly darkened by organic matter) c. E horizon d. R horizon
R horizon
The lithosphere is made up of ________.
Rock
Igneous rocks can best be characterized as ________. a. rocks containing a mixture of primary and secondary minerals b. rocks formed when molten magma solidifies c. rocks formed from the recrystallization of sedimentary material d. rocks found primarily near volcanoes. e. rocks containing both feldspars and micas
Rocks formed when molten magma solidifies
A spoonful of this has the least specific surface area. a. Sand b. Silt c. Clay
Sand
USDA considers a particle 0.09mm in diameter to be a. Clay b. Gravel c. Sand d. Silt
Sand
Which soil texture has the largest number of macropores? a. Clay b. Silt loam c. Clay loam d. Sand
Sand
_____ is not one of the textural classes. a. Clay loam b. Sandy silt c. Silty clay d. Loamy sand
Sandy silt
Which of the following categories of Soil Taxonomy provides the greatest specificity of soil properties? a. Series b. Great group c. Suborder d. Family e. Order
Series
The use of sedimentation to separate sand, silt, and clay depends upon the fact that smaller particles ___. a. are less dense b. are more dense c. settle more rapidly d. settle more slowly
Settle more slowly
The percentages of which soil components represent the minimum information necessary in order to determine the textural class of a soil? a. gravel and sand b. silt and sand c. clay and organic matter d. clay, water and air e. sand, silt and clay
Silt and sand
Shallow pots, each containing dry soils of different textures, were set in a tray of water. In which texture would moist soil first appear at the surface? (Hint: Its a pore size thing). Select one: a. Silt loam b. Sandy loam c. Sandy clay loam d. Silty clay loam
Silty clay loam
_____ is not a characteristic of soil colloids. a. Very small size b. Small external surface areas c. Electronegative charges d. Ability to exchange ions with the soil solution
Small external surface areas
Which of these compounds does not complex with phosphorus and make it less available for plant uptake? a. Aluminum b. Calcium c. Iron d. Sodium
Sodium
Which of these compounds does not complex with phosphorus and make it less available for plant uptake? a. Sodium b. Aluminum c. Iron d. Calcium
Sodium
Which of the following is not a factor affecting CEC? a. Type of clay b. Organic matter content c. Soil structure d. Soil texture
Soil Structure
The universal soil-loss equation (USLE) suggests that soil erosion loss is a product of all but one of the following factors: a. climate b. sloped steepness c. vegetative cover d. slope length e. soil drainage
Soil drainage
The P factor in the Universal soil-loss equation is concerned with all but one of the following: a. strip-cropping b. vegetative covers c. contour tillage d. soil erodibility Correct e. terraces
Soil erodibility
Select species of bacterial can infect the roots of select species of plants so that a mutually beneficial relationship is established whereby the plant obtains N and the microorganisms obtains energy. This is an example of a/an _____ relationship. a. antagonistic b. symbiotic c. parasitic d. negative
Symbiotic
The amount of different sizes of mineral particles in a soil defines the soil ________.
Texture
Tillage has the least influence on _____. a. Bulk density b. Soil strength c. Structure d. Texture
Texture
The nomenclature of Soil Taxonomy is characterized by all but which one of the following statements? a. The names give a clear indication of the modes of genesis of the soil. b. The subgroup name also tells you the great group, suborder, and order names. c. The names of the orders all end with the letters sols. d. The names are based on measurable properties and not on presumed modes of genesis. e. Soil names (except for series level) identifies major soil characteristics.
The names give a clear indication of the modes of genesis of the soil.
Where are you most likely to find the soil with the least developed soil? a. A maple and birch forest in Maine b. A temperate rainforest in Oregon c. The painted desert in Arizona d. The Great Plains of the American Midwest
The painted desert in Arizona
Which of the following characteristics of topsoil differentiate it from the underlying subsoil? a. The topsoil contains more unweathered primary minerals. b. The subsoil shows evidence of greater chemical weathering. c. The topsoil has a higher organic matter content. d. All of the above
The topsoil has a higher organic matter content.
The height of the rise of water in a capillary tube is inversely proportional to what? a. The tube area b. The matrix potential c. The osmotic potential d. The tube radius
The tube radius
If you dug a deep hole in your back yard and water started to seep into the hole it would fill the hole up to ________. a. the infiltration rate b. the percolation rate c. the liquid limit d. field capacity e. the water table
The water table
Weathering of primary minerals to form secondary minerals is an example of what type of process? a. additions b. illuviation c. transformations d. eluviation
Transformations
Weathering of primary minerals to form secondary minerals is an example of what type of process? a. additions b. illuviation c. transformations d. eluviation
Transformations
Which is one of the soil forming processes? a. Biotic Activity b. Transformations c. Climate d. Time
Transformations
Which is one of the soil forming processes? a. Transformations b. Biotic Activity c. Time d. Climate
Transformations
Which is one of the soil forming processes? a. Biotic Activity b. Transformations c. Climate d. Time
Transformations
______ is not considered one of the five major factors of soil formation. a. Native parent materials b. Living organisms c. Climate d. Translocations
Translocations
Which of the following statements is not correct? a. Where dense forests are found, soil profiles have prominent O horizons. b. Coniferous forests are found mostly in cool humid areas. c. Grasslands are found in semi-arid and sub-humid areas. d. The type of native vegetation is controlled primarily by climate. e. Tropical forests protect the soil from excessive weathering.
Tropical forests protect the soil from excessive weathering.
A soil on the south facing slope in Canada is likely to be drier and warmer than a comparable soil on a north facing slope. (T/F)
True
Algae are single-celled plants that function principally as primary producers in the soil ecosystem. (T/F)
True
Ammonification is a process by which much needed nitrogen is transformed from an organic form to a inorganic form. (T/F)
True
Which of the following is an epipedon? a. Umbric b. Kandic c. Cambic d. Spodic
Umbric
At extremely low pH values, well below 4.0, some colloids such as iron and aluminum oxides have positive surface charges, which increases the soil's ability to hold on to anions. (T/F)
True
Because of their greater surface area per unit of soil mass, silt loams soils generally have a greater capacity than loamy sand soils to adsorb water, adsorb gases, release nutrients by mineral weathering and support bacterial growth. (T/F)
True
Chemical weathering is accelerated by water, oxygen, and organic and inorganic acids moving down through the regolith. (T/F)
True
Climate influences not only the rate of weathering but the type of native vegetation dominant in an area. (T/F)
True
Compared to sands, clays will have a relatively higher porosity. (T/F)
True
Conservation tillage has generally positive effects on soil physical properties. (T/F)
True
Effective precipitation is a measure of the amount of water that flows into and through the soil profile. (T/F)
True
Epipedons are diagnostic surface horizons that are one of the primary means of classifying soils in the United States. (T/F)
True
Evapotranspiration includes vapor losses both from the soil surface and from the leaves of plants. (T/F)
True
Examples genetic horizons include A, B, C & E. (T/F)
True
Humus has a much higher cation adsorption capacity than clay. (T/F)
True
If you wanted to quickly increase the pH of a soil to 7.5 to combat a disease in cabbages you are about to plant you should use hydrated lime rather than ground limestone. (T/F)
True
In a soil with a very low cation exchange capacity, the most efficient approach to using potassium fertilizer would be to apply frequent small doses rather than a single large dose. (T/F)
True
In the south eastern United States, well aerated soils can easily be identified by the presence of bright red colors in the subsoil. (T/F)
True
Iron and aluminum hydrous oxides are characteristic of soils that are highly weathered chemically. (T/F)
True
Loess is an example of a transported parent material. (T/F)
True
Minerals that contact iron are more resistant to chemical breakdown than minerals that contain CaCO3. (T/F)
True
Mollisols are characterized by a deep epipedon that is high in organic matter. (T/F)
True
Most micronutrients play essential roles in plant metabolism as enzyme activators. (T/F)
True
Nitrogen is a component of essential plant compounds such as proteins, chlorophyll, enzymes, and DNA. (T/F)
True
The drainage class of a soil (the degree to which the soil becomes water-saturated during the year) can be judged by the presence and location of gley in the soil profile. (T/F)
True
The leaf-like structure of silicate clays involves two kinds of horizontal sheets, one dominated by a plane of silicon atoms, the other by a plane of aluminum and/or magnesium. (T/F)
True
The partial pressure (i.e. concentration) of CO2 in the soil pores is higher than the partial pressure of this gas in the atmosphere. (T/F)
True
The polarity of water helps account for the attraction of water molecules for each other. (T/F)
True
The pollution of ground water is often increased by the presence of macropores in soils. (T/F)
True
The soil erodibility factor in the Universal soil-loss equation (USLE) relates primarily to the soil's infiltration capacity and structural stability. (T/F)
True
The soils of the world contain more carbon than all the world's vegetation and the entire atmosphere, combined. (T/F)
True
The sulfur dioxide in the atmosphere resulting from fossil fuel burning, volcanoes and forest fires can be an important source of sulfur nutrition for plants. (T/F)
True
The two most significant characteristics of the classification system used in the United States are a unique system of terminology and focus on measurable soil properties as a primary basis for the classification. (T/F)
True
Tillage when the soil is too wet is likely to increase the soil bulk density. (T/F)
True
Vegetative barriers planted on the contour have been found to create low-cost "natural" terraces. (T/F)
True
Vertisols are characterized by high contents of swelling-type silicate clays. (T/F)
True
The _____ are Igneous, Sedimentary, and Metamorphic. a. types of rocks b. basic classes of soils c. master horizon names d. forms of minerals
Types of Rocks
The _____ are Igneous, Sedimentary, and Metamorphic. a. types of rocks b. basic classes of soils c. master horizon names d. forms of minerals
Types of rocks
Soils in which of the following soil suborders would most likely have a prominent E horizon under the A horizon? a. Orthents b. Udalfs c. Udolls d. Aquepts
Udalfs
A soil has a thick black A horizon, a distinct B horizon, has reasonably stable soil structure, and was formed under grassland natural vegetation. In which suborder is it most likely classed? a. ustalfs b. cambids c. udults d. aquents e. udolls
Udolls
Select the appropriate soil order: Highly weathered soils developed under forests in the humid areas. A true B horizon is present. The subsoil has a base saturation below 35%. a. Oxisols b. Ultisols c. Alfisols d. Inceptisols
Ultisols
If you were looking for a soil with high cation exchange capacity and were not concerned with the soils physical properties, which of the following would most likely fit your needs? a. Aridisol b. Oxisol c. Vertisol d. Ultisol
Vertisol
If you were looking for a soil with high cation exchange capacity and were not concerned with the soils physical properties, which of the following would most likely fit your needs? a. Vertisol b. Mollisol c. Aridisol d. Oxisol e. Ultisol
Vertisol
Liming materials neutralize soil acidity by converting the hydrogen ion into _____. a. water b. carbon dioxide c. a basic cation d. a reserve form of acidity
Water
The loess layer found atop many Midwestern soils is an example of a _____ transported parent material. a. water b. gravity c. wind d. glacial
Wind
The loess layer found atop many Midwestern soils is an example of a _____ transported parent material. a. water b. gravity c. wind d. glacial
Wind
Which of the following nutrient elements is usually present in the soil solution as a simple cation? a. B b. Zn c. Mo d. Cl e. all of the above
Zn
You would be most apt to look in _____ if you wanted to find a soil where physical weathering dominated over chemical weathering. a. a desert region of Arizona b. the foothills of the Georgia mountains c. a coastal plain area of North Carolina d. a humid region in Brazil
a desert region of Arizona
Disease suppressive soil often results from ________. Select one: a. heating the soil by natural solarization or steam heat b. repeated tillage to keep the soil bare for at least one full year c. fumigation with a volatile chemical d. adding organic materials to the soil that stimulate diverse microorganisms e. all of the above
adding organic materials to the soil that stimulate diverse microorganisms
Residual soil acidity is a measure of the _____. a. hydrogen ion activity in the soil solution b. aluminum and hydrogen ions attracted towards the charge of the clay and humus surfaces c. aluminum and hydrogen bound to the charge of the clay and humus surfaces
aluminum and hydrogen bound to the charge of the clay and humus surfaces
Which of the following locations in the United States would have the highest evaporation (E) from the soil surface in July? a. a forest woodland in Illinois b. a corn field in New York c. an unirrigated soil in South Carolina growing cotton d. a bare, unirrigated dry land soil in Colorado e. an irrigated cotton field in Arizona
an irrigated cotton field in Arizona
Soil scientists generally map the soils in a landscape by sampling the soil in ________. a. auger holes made mostly near expected soil boundaries b. the center of the suspected soil mapping unit c. pre-determined a grid-like geometric pattern of evenly spaced points d. a computer-calculated pattern of random points e. four soil pits, one dug in each corner of the area to be mapped
auger holes made mostly near expected soil boundaries
n order for nitrate to form from soil organic matter, ________ must be present in the soil a. Nitrosomonas b. Nitrobacter c. either A or B d. both A and B e. none of the above
both A and B
Where high-value crops or individual ornamental shrubs are to be grown and water is expensive, the most efficient type of irrigation to use would be _____. a. drip or trickle b. basin flooding c. furrow d. center pivot
drip or trickle
Proper fertilizer management practices encourage high water-use efficiency by _____. a. increasing the osmotic tension of soil water b. increasing the osmotic potential in the soil c. decreasing soil water tortuousity d. encouraging root proliferation
encouraging root proliferation
The water molecule is described as being dipolar. This means that water molecules can _____. a. move in two directions at the same time b. exhibit properties of both negative and positive charges simultaneously c. exist in a gas and a liquid phase at the same time d. dissolve more than one kind of substance
exhibit properties of both negative and positive charges simultaneously
Which of the following means of estimating soil water levels gives a direct measurement of the water content? a. tensiometer b. neutron scattering c. gypsum blocks d. gravimetric determinations e. pressure membrane
gravimetric determinations
Pesticides, excess plant nutrients and waste chemicals most likely to move through soils in the _____ water. a. hygroscopic b. gravitational c. capillary d. micropore
gravitational
Available phosphorus levels are constrained in alkaline and salt-affected soils because of ________. a. low hydrogen ion levels b. high calcium and magnesium levels c. high manganese levels d. high iron and aluminum levels e. high exchangeable sodium levels
high calcium and magnesium levels
The total phosphorus lost from various watersheds is most closely correlated with ________. a. high percentage of forested land b. low soil CEC c. high soil permeability d. high soil erosion e. extent of artificial drainage
high soil erosion
Water movement in a soil would be from a zone of __. a. lower potential to higher potential b. higher potential to lower potential c. unsaturated to saturated d. not enough information is provided
higher potential to lower potential
Active soil acidity is a measure of the ____. a. hydrogen ion activity in the soil solution b. aluminum and hydrogen bound to the charge of the clay and humus surfaces c. aluminum and hydrogen ions attracted towards the charge of the clay and humus surfaces
hydrogen ion activity in the soil solution
The nutrient element magnesium is often supplied by which type of application? a. broadcast of the nearly pure element as a solid b. broadcast of a chloride salt c. application of a chelate to the soil d. injection of a gas into the soil e. incorporation of powdered limestone rock
incorporation of powdered limestone rock
The nutrient element magnesium is often supplied by which type of application? a. broadcast of the nearly pure element as a solid b. incorporation of powdered limestone rock c. injection of a gas into the soil d. broadcast of a chloride salt e. application of a chelate to the soil
incorporation of powdered limestone rock
Which of the following silicate clays would be least apt to be formed from the mere alteration of primary minerals? a. iron or aluminum oxides b. chlorite c. smectite d. vermiculite e. fine-grained micas
iron or aluminum oxides
Residual parent materials are best described as a. materials formed under organic residues b. materials formed by weathering of rocks and minerals in place c. materials transported from one location to another d. None of the above.
materials formed by weathering of rocks and minerals in place
Residual parent materials are best described as a.materials formed under organic residues b. materials formed by weathering of rocks and minerals in place c. materials transported from one location to another d. None of the above.
materials formed by weathering of rocks and minerals in place
An anion is _____. a. the major source of calcium b. negatively charged c. held tightly due to CEC d. a positively charged atom
negatively charged
If you want to maximize the quantity of vegetative cover on soil which of the following tillage practices would you use? a. no-tillage b. stubble mulch c. conventional moldboard plow d. strip till e. ridge tillage
no-tillage
The categories of Soil Taxonomy, listed in order from from the broadest soil description to the most specific soil description definition, are: _____. a. order, suborder, great group, subgroup, family, series b. great group, subgroup, order, suborder, family, series c. series, family, great group, subgroup, order, suborder d. order, suborder, great group, subgroup, series, family
order, suborder, great group, subgroup, family, series
A mollic diagnostic horizon would be noted for its high degree of ______. a. iron and aluminum accumulation b. clay content c. eluviation d. organic matter accumulation
organic matter accumulation
Mycorrhizae primarily affect plant growth by influencing plant uptake of _____. a. water b. nitrogen c. phosphorus d. carbon dioxide
phosphorus
Within the technical capabilities of the particular lab, most soil test results can be best interpreted as indicating the ________. a. probability (likelihood) that nutrient application will improve plant growth b. amount or concentration of nutrient in the soil solution c. total amount of each nutrient in the soil d. amount of nutrient needed to achieve balanced soil fertility e. amount (lbs or kg ) of nutrient present in plant available forms
probability (likelihood) that nutrient application will improve plant growth
A grass cover crop grown on cropland over the winter season in a humid temperate region can be expected to ________. a. reduce the amount of nutrients leached to the groundwater b. significantly reduce the amount of nitrogen fertilizer that will be needed to grow the following crop c. significantly reduce the amount of water percolating to the water table d. increase nutrient concentrations in runoff water e. all of the above
reduce the amount of nutrients leached to the groundwater
The percentages of which soil components represent the minimum information necessary in order to determine the textural class of a soil? a. sand, silt and clay b. clay and organic matter c. silt and sand d. clay, water and air e. gravel and sand
silt and sand
The amount of available water contained in the soil is primarily a function of _____. a. particle density b. pore size distribution c. bulk density d. total porosity
size distribution
Which of the following will not increase the efficiency of water use by plants in an irrigation system? a. the use of crop residues to reduce evaporation b. the use of drip irrigation for fruit trees c. the use of concrete-lined delivery ditches d. the use of flood irrigation for forage crops e. the use of herbicides to control weeds
the use of flood irrigation for forage crops
Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are) true for the electrical resistance block? a. would give the same reading for both a loamy sand and a silt loam if both contained 15% moisture b. good to turn on automatic irrigation at -50 kPa c. requires "destructive sampling" for each measurement d. used to turn on irrigation when soil moisture potential reaches -200 kPa e. both A and D
used to turn on irrigation when soil moisture potential reaches -200 kPa
Hydrophobic soils are so named because the soil particles are coated with _____. a. water absorbent substances b. a thin water film c. a thick water film d. water repellent substances
water repellent substances