To protect their seeds, trees have different cases that cover them.


acorn oak tree


berries mulberry tree cone


evergreen tree


apple apple tree


COVER: JUAN CARLOS VINDAS/MOMENT/GETTY IMAGES; PAGES 2-3 © B.G. THOMSON/SCIENCE SOURCE/ARDEA.COM; PAGE 4 JUAN CARLOS VINDAS/MOMENT/GETTY IMAGES; PAGE 5 © KONRAD WOTHE/MINDEN PICTURES; PAGE 6 (BIRD ILLUSTRATION & LEAVES) SKELOS/SHUTTERSTOCK; (MAP) MAPPING SPECIALISTS, (MAYAN CALENDAR) FEBRIS/SHUTTERSTOCK, (AZTEC MASK) DIGITAL N/SHUTTERSTOCK; PAGE 7 (QUETZALCOATL) © MIREILLE VAUTIER/ALAMY STOCK PHOTO, (HEADRESS) MUSEUM FUR VOLKERKUNDE/BRIDGEMAN IMAGES, (1987 CUBA STAMP) LENA LIR/ SHUTTERSTOCK, (FLAG) JBOY/SHUTTERSTOCK; PAGES 8-9 MALLARDG500/MOMENT OPEN/GETTY IMAGES; PAGES 10-11 © PAT CANOVA/ALAMY STOCK PHOTO; PAGES 12-17 (LEAF BORDER) K. NARLOCH-LIBERRA/SHUTTERSTOCK, (BRANCH) XPIXEL/SHUTTERSTOCK; PAGE 12 (LEAF) OLEGUSK/ SHUTTERSTOCK, (TREE) SUNSINGER/SHUTTERSTOCK, (BARK) © AGE FOTOSTOCK/ALAMY STOCK PHOTO, (ROOTS) SITTITAP/SHUTTERSTOCK, (NURSE LOG) © NEIL LUCAS/NPL/MINDEN PICTURES; PAGE 13 © ROBERT BUSH/ALAMY STOCK PHOTO, (INSET) © DUNCAN SELBY/ALAMY STOCK PHOTO; PAGE 14 (TREE RINGS) © AGE FOTOSTOCK/ALAMY STOCK PHOTO, (LEAVES) MADLEN/SHUTTERSTOCK; PAGE 15 (BACKGROUND) MAXIM TUPIKOV/ SHUTTERSTOCK, (WIDEST) ML HARRIS/PHOTOGRAPHER’S CHOICE RF/GETTY IMAGES. (BIGGEST) © SUNNYPHOTOGRAPHY.COM/ALAMY STOCK PHOTO, (TALLEST) MICHAEL NICHOLS/NATIONAL GEOGRAPHIC CREATIVE; PAGES 16-17 (RAINBOW TREE) IIYA IMAGES/SHUTTERSTOCK, (BARK) THITIWAT CHIRAYUTWIBUL/SHUTTERSTOCK (MANGROVE TREE) EYE-BLINK/SHUTTERSTOCK, (ROOTS) © KIP EVANS/ALAMY STOCK PHOTO, (BAOBAB TREE) SHINELU/SHUTTERSTOCK, (BARK) PIERRE-YVE BABELON/SHUTTERSTOCK. PAGE 18-19 (LANDSCAPE & INSET) JOE CULTER; PAGES 19-23 (NETS) KLETR/SHUTTERSTOCK; PAGES 20-23 (BACKGROUND) LULIAS/SHUTTERSTOCK; PAGE 20 (MAP) DIKOBRAZIL/SHUTTERSTOCK; PAGE 24 (MULBERRY) MADLEN/SHUTTERSTOCK, (ACORN) © D. HURST/ALAMY STOCK PHOTO, (APPLE) © PHOTO CUSINE RM/ALAMY STOCK PHOTO, (PINECONE) PETE WILL/ E+/GETTY IMAGES


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