PLS 2- Chapter #9- Soil pH

What does soil pH measure?

• The soil's texture

• The amount of organic matter in the soil

• The soil's color

• The acidity or alkalinity of the soil

What pH range is considered neutral for soils?

• 6.5 to 7.5

• 4.5 to 5.5

• 5.5 to 6.5

• 7.5 to 8.5

Which of the following pH values indicates strongly acidic soil?

• 7.0

• 6.0

• 8.0

• 5.0

What is the effect of lime on acidic soils?

• It makes the soil more acidic

• It has no effect on pH

• It lowers the pH

• It increases the pH

Which nutrient is more available in acidic soils?

• Molybdenum

• Calcium

• Phosphorus

• Zinc

What is the typical pH range for soils in higher rainfall areas?

• 6.5 to 9.0

• 5.0 to 7.0

• 3.5 to 5.0

• 7.0 to 10.0

What is a common problem with extremely alkaline soils?

• High levels of phosphorus

• Low levels of hydrogen ions

• High levels of organic matter

• High levels of sodium

Which of the following can lower soil pH?

• Organic matter

• Dolomite

• Lime

• Crushed sulfur

What is the effect of strongly acidic soils on plant growth?

• Poor growth due to nutrient deficiencies and toxicities

• No effect on plant growth

• Improved growth due to high nutrient availability

• Improved growth due to high organic matter

Gardeners will sometimes add lime to soils that are too acidic. Lime acts as a fertilizer and raises the pH of the soil to an appropriate level.

What soil pH most likely requires the application of lime?

• 4

• 7

• 9

• 11