Vegetation Protocol and CAP LTER

Many of the questions CAP LTER vegetation researchers are interested in are centered around the human influence on the plants. How do human chose the plants for their landscapes, how do they take care of them, and what effect does all this have on plant growth? In combination with other monitoring efforts questions are asked about how plant diversity and plant growth affect other populations in the city such as birds and bugs.

At CAP-LTER we distinguish between long-term monitoring, one time observations and manipulative experiments. All of which are applied to vegetation research. We monitor changes in vegetation structure at 200 sites randomly located throughout the city and surrounding desert and agricultural lands every five years (2000, 2005, 2010, etc.). In this project, the survey 200, size and exact location of every plant in a 900 square meter plot is recorded. At a subset of these sites a more intensive monitoring of plant growth takes place. One time observations have been used to re-survey plant communities in desert remnants that were described 20 year earlier. Concentrations of elements in leaves and lichens have been measured throughout the area to document distribution of air pollututants. In manipulative experiments the effect of different landscape practices on plant performance is being tested. Popular landscaping plants are treated with different amounts of irrigation, different ways of pruning and different mulching materials. All of which influences the growth and the water needs of these plants. Your schoolyards will another site that can be used for long-term monitoring or even manipulative experiments.

Information about your schoolyard vegetation can be used in conjunction with other Ecology Explorer protocols. For example the type of vegetation may influence the kinds of arthropods students find in the arthropod survey protocol. Schools which are installing a native habitat in their schoolyard should keep careful measurements of the vegetation. CAP LTER scientists also encourage you to do vegetation surveys in vacant lots, parks and golf course.

Comments on the Protocol:

The method for surveying plants in a schoolyard is different than using a transect method to survey plants in a desert remnant. The methods described for measuring plant attributes are similar to those used by CAP LTER scientists conducting our '200 point' survey.

Grade Level:

Identifying plant types can be done with the early grades, identifying them to species requires reading and sorting skills. Measuring circumferences and areas can also be done by all grades, but calculations of tree height and areas need students with higher math skills (above 4th).

What is Growing at Your Schoolyard : Ecology Explorers Vegetation Protocol

The Sonoran Desert has the most diverse native plant species of any desert in the world. Many plants are uniquely adapted to living here and they are part of food webs that include animals and insects that also are adapted to desert living.

Phoenix is an ever-expanding urban area located within the Sonoran Desert. CAP LTER scientists are studying the impact of this urbanization on plant communities.

Over the past 100 years, people have removed a lot of native vegetation and planted nonnative plants, trees, and shrubs. But there are still some desert remnants (areas that have been preserved as Sonoran Desert landscape) within the Phoenix metropolitan area.

CAP LTER scientists are conducting plant surveys across the Phoenix metropolitan area. They will be comparing the survey results to studies done 20 years ago. They also are interested in comparing vegetation in desert remnants to that in residential areas, parks, golf courses and vacant lots.

You can participate in this study by comparing schoolyard and, or backyard data to the surveys CAP LTER scientists are doing at 200 sites around the valley. You may also decide to correlate your vegetation studies with the LTER Ecology Explorers' bird and insect studies.

Why study vegetation:

- Plants form the basic foundation of food webs and support other life forms.

- Native plants have unique adaptations for living in desert environments.

- Nonnative plants have different requirements (soil, water, nutrients) than native plants.

- The vegetation can influence the kinds of animals that are attracted to the area.

- Vegetation can be a sensitive indicator of change in local or regional environments.

What vegetation should we study:

The items most commonly found in a school yard include grass, trees, shrubs, cacti, and ground cover.

What does vegetation tell us about the urban environment:

Vegetation tells us about other environmental factors such as nutrient or water availability.

Differences between residential areas and desert remnants tell us about human behavior and decisions to alter the landscape.

Not all residential areas are alike, so it is also worthwhile to compare differences among schoolyards and, or backyards. There may be many factors that help to explain why certain types of vegetation are planted in particular areas.

Identifying non-native vegetation contributes to understanding similarities and differences between animal populations in desert remnants and residential areas.

Materials you will need:

• Map of Your School (see 'Getting Started' if you have not made a map yet)
• Pencil
• Data Sheet
• Protractor
• Ruler
• Metric Tape Measure
• Metric Measuring Wheel (optional)

Vegetation Protocol

Measure (see methods below) and identify (see identification keys)

A). Size of yard: measure perimeter, use geometry to calculate area.

B). Estimate percentage of landcover in your study area. Record your findings in the habitat description data sheet. You will need to do this before entering data into the CAP LTER database. YOU ONLY NEED TO DO THIS ONCE PER AREA OF STUDY.

C). Record the number, identity and size of trees:

1. count trees

2. identify species (orange) or category (palm)

3. measure circumference at breast height (CBH)

4. estimate height

5. estimate size of canopy

D). Record the number, identity and size of cacti

1. count cacti

2. identify species

3. measure CBH for tall cacti (area) covered to smaller cacti

4. measure height: for small cactus use a tape measure, for large cactus estimate following procedure for trees

E). Record the number and size of shrubs:

1. count shrubs

2. identify species

3. use tape measure to measure height and canopy

4. give id numbers to the plants you will be measuring

Methods

A and B: To measure area use either a long tape measure or a measuring wheel to measure the length and width to get the area

C3 and D3: To measure the circumference of trees and tall cacti use a tape measure and wrap around the trunk of the tree. Measure at the same height for each tree or cacti. Typically this height is about 1.35m from the ground (if your students are short, than use a lower height, but make sure it is the same for all measurements)

C4 and D4: To estimate the height of trees and tall cacti:Method 1: Attach a plumbline at right angles to an isosceles right triangle made of cardboard. Move until you can sight the top of the tree along the sloping edge of the triangle. Keep the upright edge vertical using plumbline. Measure the distance from the tree. Add your eye height to give you the tree's height. Method 2: Measure your shadow. Measure the tree's shadow (make your shadow measurement during the same time of day). Calculate the tree's height using the following:

Height of tree divided by the tree's shadow ‘equals' your height divided by your shadow

Alternatively, you can place a meter stick upright and measure its shadow in place of measuring the student's shadow.

C5: To estimate the size of the tree canopy: Method 1: Measure the perimeter of the canopy and use geometry to calculate area. Method 2: Measure the diameter of the canopy, assume it is a circle and calculate the area.

Formulas for Geometric Shapes:

Area of a square or rectangle equals length x width

Area of a circle equals pi r2 (r equals radius, pi equals 3.14)

Area of a triangle equals (0.5) base x height