What Happens:

      Students are introduced to a prepared, experimental garden. This garden provides the focus for the development of hypotheses / questions about the distribution and abundance of plants in this garden. These hypotheses are developed by the students with minimal guidance from the instructor. Student research groups are formed during the second week of the experiment to first facilitate data collection and later to facilitate student collaboration on data analysis, hypothesis generation, and experimental design. Students first make qualitative observations of the plants and then sample plant distributions and abundances using line transects. Students also map positions of rare plants (i.e. relatively low abundance plants in this plot). Students collect several abiotic variables across the plot as potential independent variables. Some sample processing and data sharing occur in the lab. For example, soil moisture and soil texture samples are processed in the lab. Students perform background research for their hypotheses, design experiments, and describe their experiments in a proposal. Information needed by students, for example background on experimental design, is provided during lab periods throughout the semester.

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Lab Objectives:

     At the conclusion of this lab, students will be able to...

1. perform background research to investigate 4 specific hypotheses / questions about the abundance and distribution of plants,


2. formulate an experimental program to investigate 4 specific hypotheses / questions about the abundance and distribution of plants,


3. propose an experimental program, orally and in a formal proposal, to investigate 4 specific hypotheses / questions about the abundance and distribution of plants,


4. act collaboratively to collect and analyze data, design data presentations, research the literature, and design experiments.

      It is important to note early in this guide an underlying pedagogical goal of this experiment. Students perform activities and practice processes in order to learn how science is done. In short, students are meant to learn methods for acquiring new knowledge. This is one of three possible pedagogical or scholarly goals shown in the Inquiry framework (http://tiee.ecoed.net/teach/framework.jpg). Much of the inquiry done by students in this experiment is student generated and therefore “owned” by the student.

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Equipment/ Logistics Required:

* Required: prepared experimental garden, plant presses, 50 meter tape, stakes or flags for line transects, string for line transects, plant identification resources, sample bags, drying oven, electronic scales, graduated cylinders for soil textural class measurement,

* Optional / useful: light meter, soil pH meter, soil fertility kits for nitrogen and phosphorus, digital camera, transportation for instructor and students if garden plot is off campus.

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Summary of What is Due:

      Students are evaluated on 5 assignments delivered throughout the lab. First, each student delivers an annotated bibliography of at least 15 primary research references. Second, each student provides graphs of data they collected and that are important to the research he / she is proposing. Next, students give 2 oral presentations in research groups. Last, students assemble and integrate background research, data, and experimental designs into a research proposal.

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Keyword Descriptors:

Principal Ecological Question(s) Addressed:    The ecological questions addressed are determined by student groups, in consultation with the instructor, and generally concern hypotheses about causes of spatial and temporal patterns in plant population and community ecology in the prepared experimental garden.

Ecological Topic Keywords:    The ecological keywords are determined by students’ choices of hypotheses. In the past, this has included broad concepts such as interspecific competition (shoots and roots), herbivory, mutualism (and potential mechanisms of these interactions), life history differences among grasses and forbs, physiological ecology (hydraulic lift), seed dispersal and germination strategies, specific limiting factors leading to competition, and environmental correlates of species diversity.

Science Methodological Skills Developed:    observation, quantitative plant sampling, soil moisture analysis, soil texture analysis, library research, hypothesis / question formulation, question / hypothesis clarification, experimental design, factorial experiment, research proposal writing, oral presentations.

Pedagogical Methods Used:    small group conferencing, cooperative learning, group data collection, student-directed inquiry, bounded inquiry