A Tree of Trees: What s in a name?

Transcription

1 A Tree of Trees: What s in a name? Introduction Like us, trees have names and are organized into families. Most of the families are arranged so that similar trees are grouped, or related. This usually means that trees with similar characters like leaf shape, flower patterns, bark, and fruit type are put together. We call this idea of grouping things at different levels a hierarchy. We use hierarchies all the time to explain the order of things. Consider your family tree or the way our government is set up with the President at the top. We use this concept of ordering to organize all living things because to understand and study our natural world, we need a way to understand how they are related. To organize living things, a specific name is assigned that is made of two parts, the genus name and the specific epithet. Together these two names make the species name and we refer to this type of naming as binomial nomenclature. These names are in Latin, which helped to standardize the names for living things around the world. Most living things also have common names, but these can vary across different cultures making it confusing at times. The Latin name given to a species usually reflects something about its character or is named after the person that discovered it. We define species names through writing descriptions of what they look like, including any sort of expressive term like measurements and color that distinguishes this species from the next. We will include common names with the scientific names in the activity. Wouldn t you like to have something named after you that would be recorded forever? We would like to introduce a gymnosperm family, or trees with naked seeds, and an angiosperm family, or flowering producing trees as the two examples for this lesson. The Pinaceae, or Pine family is commonly considered to be evergreen because of their needle-like leaves and the Fagaceae, or Oak family is considered to be deciduous because they lose their leaves in the winter. These are two of the plant families represented in the tree collection of the Smithsonian Gardens and will give you an idea of how trees are named. Family hierarchy: Example: Family name Pinaceae Species name (2 parts) Pinus virginiana Genus Pinus Specific epithet virginiana

2 A Tree of Trees: What s in a name? Vocabulary Scientific name Hierarchy Gymnosperm Angiosperm Dichotomous Key Flora Learning Goals: Students will learn about scientific inquiry and how things are related and grouped together, or put into a hierarchy Strengthen classification and organizational skills Learn how to use a dichotomous key Use measuring tools to compare and order things What you ll need: Activity sheet with pictures Notebook/ paper Colored pencils Ruler Magnifying glass or small hand-lens Camera (if possible for the teacher) Useful sources: A plant key or flora of your area The Names of Plants. By David Gledhill. Cambridge University Press, 4 th Ed Botanical Latin. By William T. Stearn. Oregon, Timber Press, Fact Sheets: USDA Plants: Virginia Tech, Dept. of Forest Resources and Environmental Conservation: For younger students I can name 50 trees today!: All about Trees. By Bonnie Worth. Random House,

3 A Tree of Trees: What s in a name? Activity: In the classroom or at home: Read introduction and review vocabulary. Discuss what it means to classify, or group things together and introduce what a dichotomous key is and how it is can be used to help identify organisms. These keys are similar to a chose your own adventure, because you have questions and make choices that lead to the next step. * Next discuss how all living things are grouped together and given names, similar to the way we are named. Discuss how humans scientific Latin name is Homo sapiens and how our common name is our given family name, like George Washington. Explain that one level of grouping is considered to be a family, the next level a genus, and the last level the specific epithet. The genus and specific epithet name form the species name. Share the two plant family trees from this lesson with your students and go over the definitions of the Latin names. Please note that these are two examples of plant hierarchies, and examples from the Smithsonian Gardens, but there are more names that would normally be on the family trees for both families. Have students complete the activity using the dichotomous key to figure out the names of the pine and oak trees from the images provided. Get outside: Use the images provided to go out and find a pine or oak around your school or community. Or explore the grounds of the Smithsonian Gardens and see if you can locate some of the trees indicated on the family trees in this lesson. The trees used here are located in the following gardens: NMNH, RIPLEY, HSG, NMAI, and HAUPT. Use the map of the garden to find your way. Outside Activity: First, find a shady spot under a tree and have students group themselves together depending on height. They can decide how many groups to make. Next, they can divide their groups into subgroups depending on hair color and then by shoe size. Finally, come up with a name in two parts that describes your group. Have each group share their hierarchy with the rest of the class. Ask these questions: o Do you see how this is similar to the Pine and Oak family tree examples? o Do you see how we use characters to organize and group things together? * Review plant descriptions and introduce terms for parts of trees For Teachers: Answers for the following activity sheets. Pinaceae Family: 1 Pinus bungeana, 2 P. virginiana, 3 P. thunbergii, 4 P. cembra, 5 P. pinea Fagaceae Family: 1 Quercus alba, 2 Q. palustris, 3 Q. phellos, 4 Q. bicolor, 5 Q. rubra

4 Latin Name Common Name Meaning Cedrus cedar the ancient Greek name, for a resinous tree with fragrant wood deodara divine tree Picea spruce Pitch (the ancient Latin name, pix, refers to the resinous product) omorika from the Serbian name for Picea omorika pungens ending in a sharp point, pricking Pinus pine the ancient Latin name, pinus, for a cone-bearing tree bungeana lace bark pine for A. von Bunge ( ), herbalist of Kiev, Ukraine cembra pinea the old Italian name for the arolla or Swiss stone pine; some derive it from German, Zimmer, a room cone-producing, of pines, resembling a pine thunbergii for Carl Per Thungberg ( ), Swedish physician and professor at Uppsala, who travelled in Africa, Japan and Batavia virginiana Virginia pine from Virginia, USA

5 Dichotomous Key activity: Use the dichotomous key to determine what five pine species are in each picture. Dichotomous Key to the Pines (Pinus) from the Pinaceae tree A. Are the needles single in whorls around the branch. Pinus pinea A. Are the needles clustered, or bundled (fascicle).. Go to B B. Are the needles clustered, or bundled in groups of 2.. Go to C B. Are the needles clustered, or bundled in groups of 3 or more Go to D C. Are the cones on your tree broad, egg-shaped and cm long Pinus virginiana C. Are the cones on your tree found at the end of the branch, symmetrical and 4-7 cm long Pinus thunbergii D. Are the needles clustered, or bundled in groups of 3 Pinus bungeana D. Are the needles clustered, or bundled in groups of more than 3. Pinus cembra (5 per bundle) Tip: Use the Latin descriptions as hints to figure out what Pine you have! 1. One bundle or fascicle 2. Needle cm long

6 Cone at the end of branch

7 Latin Name Common Name Meaning Castanea chestnut old Latin name for the sweet chestnut pumila Allegheny chinquapin very small, low, small, dwarf Fagus beech the Latin name, for the beech tree, from the edible seed of beech grandifolia American beech with large leaves sylvatica European beech wild, of woods or forests Quercus oak the old Latin name, quercus, for an oak alba white oak bright, dead-white bicolor swamp oak two shades of red, bicolor-rosea palustris pin oak of swampy ground phellos willow oak cork rubra red oak red Descriptions from David Gledhill s book, The Names of Plants, 4 th Ed. Cambridge University Press, 2008.

8 Dichotomous Key activity: Use the dichotomous key to determine what five oak species are in each picture. Dichotomous Key to the Oaks (Quercus) from the Fagaceae tree A. Is your leaf edge indented/ lobed, or pointy Go to B A. Is your leaf edge smooth with no lobes. Quercus phellos B. Are the lobes on your leaf 5-7 smooth rounded lobes.. Quercus bicolor B. Are the lobes on your leaf 7-9 smooth rounded lobes.. Quercus alba B. Are the lobes on your leaf 5-7 toothed or wavy lobes Quercus palustris B. Are the lobes on your leaf 7-11 pointy, toothed lobes. Quercus rubra 7-9 lobes lobes 2. Photos Courtesy: Virginia Tech, Dept. of Forest Resources and Environmental Conservation

9 3. 4. Photos Courtesy: Virginia Tech, Dept. of Forest Resources and Environmental Conservation 5. more than 7 lobes