WILDFLOWER/POLLINATOR LAB

• Goal: to identify wildflower species, predict their pollination system, and identify pollen vectors.
• Preparation: know where at least five wildflower species occur.
• Time Necessary: about 2 hours
• Equipment: wildflower identification book, polyclave key to pollination systems, data sheet, pencil.
• Turn in: the Pollination System Data Sheet in html or in Microsoft Word format; see sample below.

OBJECTIVES:

1. To obtain experience in natural history field research and techniques.
2. To identify wildlflower and pollinator species occuring here.
3. To better understand pollination systems.

BACKGROUND:

Plants are rooted in place. This poses a problem when plants want to mate -- how is the sperm going to get transferred to the egg? Plants package their sperm in specially-designed capsules (called pollen grains) and then use pollen vectors -- wind, water, and animals -- to propel the pollen from one plant's anthers (where pollen is produced) to another plant's stigma (which receives the pollen). This process of transferring pollen from anther to stigma is called pollination. Plants have evolved specialized adaptations to help ensure their pollen vector's interest in and success at picking up, transporting, and leaving off the pollen at the appropriate place (e.g. providing food or housing materials for their animal vectors and making aerodynamic or sticky pollen). Animals, in turn, have evolved special adaptations to increase their effectiveness at acquiring the goodies provided by the plants (e.g. wings, long tongues, scrapers, and holding devices). A variety of pollination systems have resulted from the interactions between plants and their corresponding pollen vectors. Recommended Reading: The Forgotten Pollinators by Stevem Buchmann and Gary Nabhan (1996). Also see textbook pp. 144-146. This lab was adapted from Tyrrell, L. 1989. How is this flower pollinated? Journal of College Science Teaching 18:378-383.

PROCEDURE:

• Find a wildflower in bloom.
• Use the Southern Arizona Wildflower Guide (published by the Tucson Citizen) or other field guide to identify the wildflower. Record its name in the space provided on your Data sheet (html / word)
• Use the Polyclave Key to Pollination Systems (Tyrrell 1989) to determine the probable pollination system for that wildflower.
  • Look at each flower character, record the best description that matches your species in the space provided, then cross out those pollination systems listed as not involved and put parentheses around those that are unlikely but possible (those in parentheses in the key).
  • After all flower characters have been examined, the pollination system or systems not crossed off are the ones likely or possibly (if still in parentheses) involved with your wildflower. Note: some plants may use more than one pollination system. Record the proposed pollination system(s) in the space provided (e.g., bees and possibly butterflies).
• Throughout the observation period, record any observations of wildflower/pollinator interactions. Realize, though, that some insects visit flowers, and may even take the goodies, without actually transferring pollen (technically referred to as cheats). Record the species that come in the possible pollen vectors observed line on the data sheet.
• Repeat for a total of 5 wildflowers.
• See sample below for how one species would be filled in on the data sheet.

  Note: You must give all 4 flower descriptions used (symmetry, shape, color, and odor).
Note also that for flower color, you only have a few choices and you must use one of those choices (for example, if your flower is orange, you have to choose either yellow or red).
Note that being radial removes nothing. Not tubular crosses out MO and BA and puts parentheses around BU and BI.
Yellow crosses out WI, BT, F-M, F-S, MO, BA.
Fragrant crosses out WI and F-S and also now crosses out BI which used to be in parentheses.
So you are left with bees (not crossed out) and possibly (in parentheses) butterflies.
Note any insects, etc. that visited your flower species under possible pollen vectors observed.

Record these data on the Pollination System Data Sheet (html / word) and turn in.

Jump to Lab Manual, Polyclave Key or Data Sheet (html / word)