Exam 3: Soil Classification

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

The name of a subgroup indicates the order,suborder,and great group of which it is a member.

The categories of Soil Taxonomy can be listed from the broadest (first)and most specific (last)as: order,suborder,great group,subgroup,series,family.

The two most significant characteristics of the classification system used in the United States are a unique system of terminology and focus on measurable soil properties as a primary basis for the classification.

Investigating the soils of northern Canada on summer,you dig a soil pit easily though fairly uniform peat material until,at 75 cm deep,your shovel hits a layer that is frozen solid.Into which type of soil are you most likely digging?

In soils of which great group would you most likely find wide surface cracks during periods of dry weather?

A soil pedon is ____.

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

Because soil development is just beginning in Entisols,these soils are generally less variable in properties than are those in the Andisol or Ultisol orders.

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

An argillic horizon is a diagnostic horizon characterized by the subsurface accumulation of silicate clays.

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

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

Epipedons are diagnostic subsurface horizons that are one of the primary means of classifying soils in the United States.

In which soil orders would recent alluvium most likely be a common parent material?

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

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?

Human influence on the formation of soils,such as many urban soils,is highlighted at what level in Soil Taxonomy?

The broadest category of classification in Soil Taxonomy specifies 12 soil orders,11 of which are for mineral soils.

Soils in which of the following soil suborders would most likely have a prominent E horizon under the A horizon?