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What is the difference between a saguaro cactus and a prickly pear cactus?
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The main difference between a saguaro cactus and a prickly pear cactus is that the saguaro has spines on its outer layer, while the prickly pear does not. Additionally, the saguaro cactus can grow up to 20 feet tall, while the prickly pear cactus typically grows around 6-8 feet in height.