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 25 cacti and shade DHJanzen100336.jpg high resolution
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| The same species of cactus in DHJanzen100335.jpg can invade, however, tropical dry forest to some degree (and also see image DHJanzen100010.jpg). During the dry season, again as with Jacquinia nervosa above, this Costa Rican cactus grows well in the dry season when the general canopy is leafless and shuts down in the rainy season when the canopy overhead shades it, as in this image. Indeed, cacti may be viewed as the epitomy of the green trunk strategy illustrated in image DHJanzen100319.jpg above. Cacti have evolutionarily converted their leaves into thorns (dead tissue, I should add) and the desiccation-resistant (and water-storing) stem is the photosynthetic organ. | ||
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