Students ask questions about possible allelopathic interactions between the identified plants. Choose several plants to test for possible allelopathy. Decide which seed or seeds will be bio-indicators. Record in journal. Collect 10 or more leaves for each chosen plant.
Place leaves in labeled plastic bags.
Try to guess which plants might be allelopathic from observing the plants in their natural setting. Record field observations. Refrigerate leaves if next step is not immediate. Tear the leaves into small pieces and place in a labeled jar. Add 100 ml of distilled water and crush leaves with a spoon, stirring to mix.