Soil and Water Flashcards

Which soil horizon is most important for tree root development and nutrient uptake?

Answer: A horizon (topsoil)

The A horizon contains the highest concentration of organic matter and microbial activity, making it critical for root growth and nutrient absorption.

What does the term 'field capacity' refer to in soil science?

Answer: The amount of water remaining in soil after excess has drained by gravity

Field capacity is the water content remaining in soil after gravitational drainage has ceased, typically measured 24–48 hours after saturation.

In Albuquerque's arid climate, which irrigation strategy best promotes deep root development in trees?

Answer: Infrequent deep watering less often

Infrequent deep watering encourages roots to grow deeper in search of moisture, improving drought tolerance and structural stability.

What is the primary cause of soil compaction around urban trees?

Answer: Foot and vehicle traffic

Foot and vehicle traffic are the leading causes of urban soil compaction, reducing pore space and limiting water infiltration and root growth.

Which nutrient deficiency in alkaline Albuquerque soils most commonly causes interveinal chlorosis in trees?

Answer: Iron

Iron chlorosis is common in Albuquerque's alkaline soils because high pH locks up iron in insoluble forms, causing yellowing between leaf veins.

What soil amendment is most commonly used to lower pH in alkaline desert soils?

Answer: Elemental sulfur

Elemental sulfur is oxidized by soil bacteria to form sulfuric acid, which effectively lowers soil pH in alkaline conditions over time.

Which of the following best describes 'wilting point' in relation to soil water?

Answer: The soil moisture level below which plants cannot extract water

The permanent wilting point is the soil moisture level at which the remaining water is held too tightly by soil particles for plant roots to extract it.