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Sailing Seeds:

An Experiment in Wind Dispersal

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Curricular Materials to Accompany the McIntosh Apple Development Poster
Distributed by the Education Committee of the Botanical Society of America
Posted March 2001

Grade Levels: 6-8; 9-12

Abstract: Many plants rely on wind to carry their fruits or seeds. In this activity, students explore the mechanism of wind dispersal by creating their own model fruit and evaluating the relationship between the fruit structure and its dispersal ability.

At the end of this exercise, students will be able to:

    Dispersal  of seeds is important for the continued survival of a plant species.  If plants grow too closely together, they compete for light, water, and soil nutrients; therefore, seed dispersal is a way to distribute offspring.  In flowering plants like apple trees, one or more seeds are housed within a fruit which is the portion of the apple that we eat.  Sweet fruit like apples are eaten by animals that disperse the undigested seeds.  In contrast, some plants have fruit that remain on the plant and disperse only the seeds.  In either case, plants have evolved different dispersal mechanisms.  Some fruits can be carried by water, like the coconut.  Burdock fruits have hooks that attach to and are dispersed by animals.  Dandelion fruits are suspended from feathery "parachutes" that are carried on the wind.  The fruit of maple and ash trees have wings that let them float on air.  This activity is a fun way for the students learn how fruit or seed size and shape influence their ability to disperse by wind.  Students design their own fruit or seed and measure two important qualities that enhance the ability of it to disperse in the wind: distance travelled and time aloft.





Introductory plant biology books will discuss fruit and seed dispersal.  Several are listed below. 


This activity was developed and edited by Amy Russell and Steven Rice, Department of Biological Sciences, Union College, Schenectady, NY.