Soil Science and Irrigation Flashcards

What is 'soil compaction' and how does it affect landscape plants?

Answer: Compression of soil particles that reduces pore space, limiting air, water, and root penetration

Soil compaction reduces the pore spaces between soil particles, limiting oxygen, water infiltration, and the ability of roots to penetrate and grow.

An irrigation system's 'precipitation rate' refers to:

Answer: The rate (inches per hour) at which a sprinkler system applies water

Precipitation rate is the amount of water applied by an irrigation system per unit time (inches per hour), which must be matched to soil infiltration rate to prevent runoff.

What does 'ET' (evapotranspiration) represent in irrigation scheduling?

Answer: The combined water loss from soil evaporation and plant transpiration

Evapotranspiration (ET) represents the total water lost from the landscape through soil evaporation and plant transpiration, used to calculate replacement irrigation needs.

Which soil amendment is commonly used to improve drainage in heavy clay soils?

Answer: Coarse sand or perlite

Coarse sand or perlite added to clay soil increases pore space and improves drainage by breaking up the dense clay particle structure.

What is a 'rain sensor' or rain shutoff device in a landscape irrigation system?

Answer: A device that automatically suspends irrigation when sufficient rainfall occurs

A rain sensor automatically shuts off the irrigation system when it detects a set amount of rainfall, preventing overwatering and wasting water after natural precipitation.

What is 'backflow prevention' in a landscape irrigation system?

Answer: A valve that prevents water from flowing backward from the irrigation system into the potable water supply

Backflow prevention devices stop contaminated irrigation water from flowing backward into the drinking water supply, required by most US plumbing codes.