Soil is one of our most important, but easily overlooked, natural resources. Teachers and students interested in
the environment and natural resources are often unaware of the importance of soil. The Envirothon provides an
opportunity to introduce students to the interesting world of soils. Soils are important for growing food,
disposing of our waste, supporting our buildings and roads, growing timber and fibers (such as cotton), providing
habitat for wild animals, and many other uses. Envirothon participants will develop an understanding of the
relationship of soil to other resources they are studying. Soil has an effect on, and is affected by, other elements of the ecosystem.
Just as there are many types of plants and animals in Rhode Island, there are many different soils. As you move
across the landscape the soils change, often in predictable ways. Some soils are wet, others are droughty.
Some allow water to pass through quickly, others severely restrict water movement. Because of these kinds of
differences, people making decisions relating to land use need to know about soils. People evaluating a
particular piece of land might ask: are these soils suitable for an on-site septic system or a new street? On
other tracts of land around town people are asking about the quality of the soil for growing sweet corn or white
pine trees, for siting a landfill, for growing tall grasses to attract nesting song birds, etc.? In short, we need to know about the soils that are all around us.
Activities on Envirothon Day
During the day of the Envirothon, the students will be involved in three basic soils
activities. The activities are designed to demonstrate the student's familiarity with:
Narragansett Silt Loam
The un-official State Soil
of Rhode Island
- Important characteristics of soils - (A below).
- Field identification of soils and landscapes - (B below).
- Use and practical application of soil survey information - (C below).
A.) Students will be asked a series of questions about soils and their properties.
These will account for about 70% of the total score. Sample questions:
- The soil property that indicates the ability of water and air to move through the soil is called:
a.) cation exchange capacity
- If the lawn at your school turns brown very quickly during summer dry spells, the soil under the grass
most likely has a texture of: (select one)
a.) silt loam
c.) very fine sandy loam
d.) loamy sand
B.) Students will be asked to observe a soil pit, and its associated landscape. (Soil samples from other
locations may also be provided for them to evaluate.) Based on their observations, students will answer a
series of questions. These questions will account for about 15% of the total score. Sample questions:
- Of the soil samples provided in the two cans, which has the higher soil moisture holding capacity?
"Sample A" or "Sample B"
- In the soil pit before you there is a light gray color horizon that begins at a depth of about 29 inches.
This horizon is referred to as the: (select one)
b.) parent material
c.) gravel zone
d.) gleyed layer
C.) The students will be asked to use the Soil Survey of Rhode Island, and associated publications, to
extract information about a given tract of land and formulate conclusions. These questions will account for about 15% of the total score. Sample questions:
- Put yourself in the position of a person looking to buy a house lot so you can build your dream home. You
are considering a two acre lot in the town of Scituate, on the west side of RI Route 102, about 500 ft.
north of the junction of rt. 102 and rt. U.S 6. Based on the information given in the Soil Survey of Rhode
Island the soil at this site is rated as having _______________ suitability for "dwellings with basements"? (Fill in the blank)
- On the table before you is a soil map sheet from the Soil Survey of Rhode Island. Notice the parcel of
land that has been outlined in red. You are interested in managing this area to attract wetland wildlife. Approximately what percent of this parcel is covered by hydric (wetland) soils?