Human Impacts—How Do Trees Affect Erosion?

Summary: Students explore the concept of erosion and how it impacts environments. They also discover how trees and other factors affect erosion.

Concepts to teach: Erosion, impervious surfaces, turbidity, models, scientific inquiry

Goals: Students use a model to discover how trees help prevent erosion and turbidity.

S6.3S1, S6.3S2
S7.2E.4, S7.3S1, S7.3S2
S8.3S1, S8.3S2

Specific Objectives:

  1. Engage in scientific inquiry by conducting an experiment in the classroom.
  2. Define erosion and its effects on nearby land and water ecosystems.
  3. Determine under what circumstances erosion is likely to occur.

Activity Links and Resources:

  • How Do Trees Affect Erosion?
    • This lesson plan from in Washington outlines the classroom experiment and includes a worksheet and answer key.
    • Lincoln County teachers in the Oregon Coast Aquatic and Marine Science Partnership (OCAMP) used this experiment for a peer-to-peer teaching activity among 6th and 3rd graders. See their presentation that includes teaching objectives, techniques and student assessments.
  • Resources concerning the potential effects of changing turbidity, stream flow and temperature on aquatic species
  • Erosion Inquiry—Students conduct a simple experiment that explores the types of conditions under which erosion occurs in the school yard.


  • Use or develop formative assessment probes to gauge student understanding about the water cycle. The following probes from Uncovering Student Ideas in Science, vol. 1 could be applied or modified (to obtain Uncovering Student Ideas in Science publications or access sample chapters, visit the NSTA website):
    • Beach sand—the purpose of this probe is to elicit students’ ideas about weathering, erosion, deposition, and landforms. It may be used as is, or modified to better relate to a similar concept found in the schoolyard habitat (pebble size in streams, for example).
  • Probe: Rain on the Parking Lot—the purpose of this probe is to elicit students’ ideas about how rainwater interacts with impervious surfaces.
  • Worksheet included in the How Do Trees Affect Erosion? lesson plan.