| Question | Answer | % Correct |
|---|---|---|
| Irrigation is needed when the soil moisture deficit equals 6 inches. How long will it be before irrigation is needed if the average daily ET is 0.5 inches and one 1 inch rainfall event occurs with no runoff? Initial soil moisture deficit is 2 inches . | 10 | 100%
|
| If a field has an 11 foot change in elevation over a distance of 1000 feet, the slope is _____%. | 1.1 | 100%
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| The bulk density of 100 cm³ of dry soil that weighs 145 g is ____ g/cm³. | 1.45 | 100%
|
| The area of a rectangular field that is 1250 feet long and 700 feet wide is ___ acres. | 20 | 100%
|
| A day when there is _____ probability of precipitation would be best for pesticide application to minimize pesticide losses in runoff. | 20% | 100%
|
| Which of the following NO3- concentrations would be considered hazardous to an infant? | 44 mg/L | 100%
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| Knowing the drainage class of soil is helpful when building a __ _ | All of the above | 100%
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| Which of the following is negatively charged? | Anion | 100%
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| Subsurface compaction from tillage usually starts ____. | At the depth of tillage | 100%
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| ____ are raised soil areas used to improve drainage. | Beds | 100%
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| Phosphorus transport from a field can be reduced by ____. | Buffer strip | 100%
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| Tile drain spacing is smallest for a ____ soil. | Clay loam | 100%
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| The irrigation method where water is applied at low volume is _____. | Drip | 100%
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| When crop residues are removed from a field, soil _____ increases. | Erosion | 100%
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| Nutrient enrichment of a surface water is termed______. | Eutrophication | 100%
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| Maximum plant available water is _____ minus ____. | Field capacity, permanent wilting point | 100%
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| Which kind of soil structure would be typical for a good seed bed? | Granular | 100%
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| Poorly drained soils that are wet most of the year are often __ _ | Grey | 100%
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| Which of the following are most sensitive to saline water? | Humans | 100%
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| The stable form of soil organic matter is called ______. | Humus | 100%
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| Which of the following can decrease bulk density? | Incorporating Compost | 100%
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| Which of the following is not an example of a contribution of soil organic matter to soil properties? | Increased molybdenum availability | 100%
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| Soil microorganisms cause ______ in soil structure when crop residues are added to soil. | Increases | 100%
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| Any factor that ____ runoff and ____ surface protection, increases erosion. | increases, decreases | 100%
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| ______ decreases odor and NH3 losses from biosolids. | Injection | 100%
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| Which of the below is an example of sub-surface drainage? | Interceptor Drain | 100%
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| Water moving horizontally in a soil is called _____ flow. | Lateral | 100%
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| Which of the following pollutants is in water is not generally attributed to agriculture? | Mercury | 100%
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| Cations are held on the CEC by ____ charges on clay and organic matter. | Negative | 100%
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| Soil organic matter is a source of ____ for crops. | Nitrogen | 100%
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| What is the most important soil property that affects soil health? | Organic matter | 100%
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| In most situations, surface soil _____ will be lower after water erosion occurs. | Organic matter content | 100%
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| Rapid water movement downward in large pores after a rain is called _____. | Preferential flow | 100%
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| Which of the following is most important in carbon sequestration? | Reducing tillage | 100%
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| Maintaining surface residues on a soil will ____ surface soil warming in the Spring. | Retard | 100%
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| Good structure in the subsoil improves _____. | Root elongation | 100%
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| Phosphorus is transported by _____ from fields. | Runoff | 100%
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| Which kind of erosion removes a thin layer of soil? | Sheet | 100%
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| What is the textural class of soil that is 10 percent clay and 35 percent sand? | Silt Loam | 100%
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| The amount of soil that can be lost by erosion, while crop production is maintained economically for the long term is _____. | Soil loss tolerance | 100%
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| _____ irrigation allows the most control to prevent runoff. | Sprinkler | 100%
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| Which of the following increases as a soil's clay content increases? | Surface area | 100%
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| Seedling emergence is hindered by _____. | Surface crusting | 100%
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| Which of the following has the greatest impact on infiltration? | Surface residue | 100%
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| Which of the following has the greatest impact on infiltration? | Surface soil texture | 100%
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| Which of the following would be an acceptable conservation practice for a steep slope? | Terracing | 100%
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| The maximum value for plant available water is _________. | The difference between field capacity and wilting point | 100%
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| In order to increase soil organic matter levels, ______ must be markedly reduced or eliminated. | Tillage | 100%
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| What standards are used to determine if a water body is impaired? | Total maximum daily load | 100%
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| Maximum ET generally occurs ______. | When atmospheric demand peaks | 100%
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| Ten ppm of NO3- (mw is 62) is ____. | All of the above | 67%
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| Limited soil moisture generally _____ nutrient uptake. | Decreases | 67%
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| Sediments in runoff decrease ____ in surface waters. | Light penetration | 67%
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| Which of the following clays contributes most to CEC if the same amount of each clay is present? | Montmorillonite | 67%
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| If a soil has an EC of 0.6 siemens per meter and contains 20 percent sodium on the CEC, it is a ____ soil. | Saline-Sodic | 67%
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| Which of the following irrigation systems is least labor intensive? | Sprinkler | 67%
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| A horizon that contains illuviated clay is the _____ horizon | B | 50%
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| Soil erosion potential is highest in which of the following? | Clean-till | 50%
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| In a typical row crop production system, most of the soil organic matter originates from _______. | Crop Residues | 50%
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| Excessive soil moisture generally ____ nutrient uptake. | Decreases | 50%
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| Potassium fixation occurs when which of the following clays is present in soil? | Illite | 50%
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| Which of the following textural classes has the largest potential available water? | Silt Loam | 50%
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| Which of the following factors does not affect wind erosion? | Slope length | 50%
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| A _____ is specifically designed to improve ground water quality before ground water can move to a stream. | Tree planting | 50%
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| Which of the following is a kind of wind erosion that forms dust storms? | Suspension | 33%
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| How many acres in the S½ of the S½ of Section 29? | 160 | 0%
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| If a septic system is being planned for a housing subdivision, a __ order soil survey is needed. | 1st | 0%
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| What is the percent crop residue cover if the average number ofresidue intersections is 20 at 6 inch increments over 50 feet? | 20 | 0%
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| Well water contamination from surface water can be prevented by using a ____. | Casing | 0%
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| Which of the soil textures listed below has the highest porosity and lowest bulk density? | Clay | 0%
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| Which of the following soil textures has the greatest % porosity? | Clay | 0%
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| When organic materials decompose, most of the C ends up as ____. | CO₂ | 0%
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| Which of the following organic materials would be expected to mineralize the most nitrogen? | Dairy manure | 0%
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| Leaching is most impacted by _____. | Depth to restrictive layers | 0%
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| Which of the following must exist for ET to occur? | High temperature | 0%
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| Which of the following favors increased soil microbial activity? | Increase in soil water content from 20 to 40 percent of water holding capacity | 0%
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| Maintaining crop residues on the surface and _____ reduce surface compaction. | Light tillage | 0%
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| Soil _____ has little effect on sulfate movement. | pH | 0%
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| Which of the following increases soil water storage? | Precipitation | 0%
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| Soil structure modifies the physical properties of soil _____. | Texture | 0%
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