Exploring Scrub Communities Plant Adaptations. Edited by V. Bourdeau

Transcription

1 Exploring Scrub Communities Plant Adaptations Edited by V. Bourdeau

2 Scientists wonder: Why do so many plants and animals live only in the Florida Scrub? S. Denton One reason is that many living things seem to need special ADAPTATIONS to survive and succeed in the scrub.

3 The Florida Scrub is a difficult place to live. Living things need the right ADAPTATIONS for the special conditions found here. N. Deyrup

4 N. Deyrup Maybe, if we think about a few of these conditions, we will understand some of the unusual things about plants and animals that live in scrub.

5 Look at this scrub soil: it is nothing but sand. J. Schafer When rain falls, the water drains quickly through, like water through coffee grounds.

6 N. Deyrup In winter, there is very little rain, and the scrub can be as dry as a desert. The plants that live in scrub must have ADAPTATIONS for saving water, or they would die.

7 This Prickly Pear is a cactus, like the ones that live in the deserts of Arizona and Mexico. N. Deyrup

8 N. Deyrup The fat round parts that look like leaves are really stems that have lots of room inside to store water.

9 The needle-like spines are really leaves. T. Eisner Plants with big thin leaves, like lettuce plants or mustard greens, lose a lot of water through their leaves. This cactus doesn t lose any water through its leaves.

10 Shirley Denton When you visit the scrub you will see that many of the leaves are shiny, as if some very busy custodian had waxed each one.

11 J. Layne These leaves of a Sand Live Oak are waxed, by the plants themselves, which make a shiny surface on the upper side of their leaves.

12 When we wax a wood floor, we prevent water from getting in and staining the wood. N. Deyrup Plants wax their leaves so water cannot get out.

13 Now look at the lower side of this Sand Live Oak leaf. The microscopic holes that allow air in and out of the leaf are on the underside, so it cannot be covered with a thick coat of wax. J. Layne Instead, you see thousands of tiny whitish hairs.

14 Air holes as seen through a Scanning Electron Microscope These hairs slow down air blowing along the underside of the leaf, so the leaf does not lose water so fast from its air holes when hot, dry winds blow through the scrub.

15 Lots of scrub plants have leaves that stick up instead of lying flat. Sunlight is hottest at midday when the sun is overhead. M. Deyrup

16 N. Deyrup There are lots of thunderstorms in Florida, and when lightning strikes a pine tree in the dry scrub, there may be a big fire.

17 Animals can run away or hide in a hole, but what about those poor scrub plants? How can they survive? N. Deyrup When fire comes, scrub plants have more ADAPTATIONS which can save them.

18 K. Main Thanks to their ADAPTATIONS, scrub plants are even helped by occasional fires.

19 N. Deyrup Look at the size of this scrub oak tree.

20 Pretty shrimpy compared with this Laurel Oak! But the scrub oak keeps a lot of itself underground. N. Deyrup

21 N. Deyrup When it gets burned, it just sprouts up from its big roots. A little shoot could be coming from roots hundreds of years old, that may have survived dozens of fires that would have killed a big Laurel Oak.

22 N. Deyrup Here is a Saw Palmetto beginning to grow back after a fire,

23 and here is a Silk Bay tree. Can you see the new growth around the base of the burned branch? M. Deyrup

24 Remember that white scrub sand? J. Schafer You could never grow fruits or vegetables in that sand without adding lots of fertilizer. When the scrub burns, any dead wood and dry plant parts are burned into ashes that fertilize and help the plants.

25 R. Lavoy Some plants, like this Florida Rosemary, have seeds that won t even sprout until the scrub has burned, clearing out all the old plants and fertilizing the soil. Year after year the seeds may wait in the sand, but a fire always comes sooner or later.

26 M. Deyrup Can you name 3 ADAPTATIONS that scrub plants need to live in their harsh conditions? N. Deyrup M.Deyrup

27 Continue learning about the Big Scrub If you haven t already done so see the.pdf PowerPoint on Animals and Interdependence of the Scrub