Exam 3: Soil Classification

Which of the following soil temperature regimes would provide the warmest and least variable soil temperatures?

A pedon is a 3 dimensional field unit occupying about 1000 square meters (1 hectare) of land area.

Mollisols are characterized by a deep epipedon that is high in organic matter.

You would be more apt to find an Gelisol in Alaska than in Iowa.

Soil Taxonomy, the classification system used in the United States, was developed by C. E.Marbut and associates in the 1940s.

The map units on a detailed soil map in a county soil survey report are most likely to be labeled with names from which category of Soil Taxonomy?

Russian scientists were the first to develop the concept of soils as natural bodies.

For agricultural use in a given region, a soil with an ochric epipedon could generally be expected to be more productive than one with a mollic epipedon.

Soil scientists from which country first conceived the idea that soils were natural bodies?

A soil has a thick black A horizon, a distinct B horizon, has reasonably stable soil structure, and was formed under grassland natural vegetation.In which suborder is it most likely classed?

Soils in the Oxisols order are deeply weathered and have deep subsurface horizons of silicon oxide.

Oxisols are more highly weathered than are the soils of any other order.

The family category focuses on properties affecting plant roots and suitability for engineering uses of soils.

Which of the following subsurface diagnostic horizons would you expect to find in a highly weathered soil of the humid tropics?

The soil and a soil are two extremes in the concept of soils that is basic to most classification schemes.

Which of the following diagnostic horizons would likely not restrict root growth in soils?

In which of the following epipedons is the organic matter level generally lowest?

Which of the following describes a soil likely to contain a significant content of low activity clays?

An aquic soil moisture regime connotes a higher degree of soil moisture saturation than an ustic one.

You are seeking a soil with high clay content but one that is not sticky when wet nor hard and cloddy when dry.In which of the following suborders would you most likely find this soil?