Soil Horizons (Advanced)
This horizon contains weathered parent material with little organic matter.
What is the C horizon?
Soil with equal parts sand, silt, and clay.
What is loam?
Farming with minimal soil disturbance.
What is no-till farming?
Using natural predators to control pests.
What is biological pest control?
Approximate time agriculture began.
What is about 10,000 years ago?
The horizon minerals are leached from.
What is the E horizon?
The smallest soil particle size.
What is clay?
Plowing across slopes instead of up and down.
What is contour farming?
Combining biological, mechanical, and chemical pest controls.
What is integrated pest management (IPM)?
Main purpose of most GM crops today.
What is pest or herbicide resistance?
The horizon where leached minerals accumulate.
What is the B horizon?
Dark soil color usually indicates high levels of this.
What is humus?
Soil problem caused by irrigation in dry climates.
What is salinization?
These crops rely heavily on insects for reproduction.
What are fruit crops?
A soil-related benefit of feedlots.
What is reduced overgrazing?
The two horizons with the most biological activity.
What are the O and A horizons?
This soil property affects nutrient availability.
What is pH?
Soil degradation caused by large-scale tree removal.
What is deforestation?
Pollinator loss directly threatens this concept.
What is food security?
A major risk of monoculture farming.
What is catastrophic crop failure?
Correct order from surface to bedrock: A, R, O, B, C, E.
What is O → A → E → B → C → R?
Best soil texture for agriculture.
What is loam?
A farming method that conserves soil and disrupts pest cycles.
What is crop rotation?
The pollinator responsible for one-third of U.S. food.
What is the honeybee?
Sustainable agriculture prevents this long-term issue.
What is soil degradation?