Leaf Structures Tropical Morphology Rain Management How Plants Adapt Rain Forest Leaf Structures Rain Management The University of Georgia College of Agricultural and Environmental Sciences

About The Author Dr. Paul A. Thomas Professor of Floriculture Department of Horticulture The University of Georgia Extension Specialist Really into Photography!

Learning Objectives 1. Understand that there are two main strategies leaves exhibit for managing rainfall: Channeling water away from the plant, and channeling water to the plant root system. 2. Be able to describe why some plants capture rainfall in leaf structures that look like cups, or nests, and how other creatures that live in the rainforest take advantage of those structures.

Water Channels Almost all tropical plants that live in rainforests have leaf features that channel or direct water. This banana leaf shows how extensive this channeling can be.

Some plants channel water towards the plant root system, to ensure roots are moist.

Working together, many leaves can capture almost all the rain falling near the plant.

Plants such as this Ginger, have rigid leaves that collect and channel water, but also drain the leaves quickly to reduce chances of disease.

As you can see, rainforest plants can take this adaptation to surprising levels.

Drip Tips Drip Tips reduce leaf surface area and facilitate droplets forming, allowing gravity to drain away excess water easily.

Rainforest ferns employ drip tips on each leaflet, and also apply the same principle to the entire leaf. structure.

Most palm leaves have leaflets that allow wind to pass through the leaf, yet also channel water away from the plant.

Waxy, Thick Leaves There are many, many rainforest plants combine thick waxy leaves and channels and drip tips to can help repel moisture.

Some plants, such as epiphytic bromeliads, direct water to their centers, and hold it there to attract pollinators

What strategies does this plant employ?

Summary We have seen that there are several adaptations, or morphological features that Rainforest plant leaves have to manage rainfall. This includes leave channels, drip tips and heavy waxy leaves. The over-riding reason to remove water quickly from a leaf in a Rainforest is disease prevention.

Assessment Opportunity Explain the three main strategies plant leaves have developed to remove water qwuickly from their leaves. Do any plants in your backyard emply the same strategies? Can you think of any other potential designs for leaves that might improve upon removing water quickly from a leaf surface?

For Future Exploration http://news.bbc.co.uk/earth/hi/earth_news/newsid_8049000/8049850.stm http://www.eduweb.com/rain/rain-east.html http://www.marietta.edu/~biol/biomes/troprain.htm