LARE LARE Soils and Site Conditions 1

Question 1

According to USDA soil texture classification, which soil type has the highest percentage of sand particles?

Accepted Answer

Sandy loam

Answer

Sandy loam contains a high proportion of sand (typically 70–85% sand) with smaller amounts of silt and clay, resulting in fast drainage and low water retention.

Question 2

What does soil 'percolation rate' measure, and why is it important for landscape design?

Accepted Answer

The speed at which water moves through the soil, affecting drainage and irrigation design

Answer

Percolation rate measures how quickly water moves through the soil, which is critical for sizing bioretention facilities, septic systems, and determining irrigation schedules.

Question 3

Which USDA natural resources document is the primary reference landscape architects use to obtain detailed soil survey data for a project site in the US?

Accepted Answer

Web Soil Survey (WSS) published by NRCS

Answer

The USDA-NRCS Web Soil Survey provides county-level soil maps, series descriptions, limitations, and engineering properties for all US project sites.

Question 4

What does the term 'soil horizon' refer to in site analysis?

Accepted Answer

A distinct layer of soil with different physical and chemical properties from adjacent layers

Answer

Soil horizons are distinct horizontal layers within the soil profile (O, A, B, C) that differ in color, texture, structure, and composition.

Question 5

On a LARE site section, which layer is typically shown as 'fill' and why must it be identified?

Accepted Answer

Previously placed non-native material that may be unstable or contaminated

Answer

Fill is previously deposited non-native material that may be poorly compacted, contain debris or contaminants, and have unpredictable bearing capacity, requiring special design consideration.

LARE Test Practice Test

LARE Test Practice Test

LARE LARE Soils and Site Conditions 1