Cactus & Succulents

Succulent plants, or succulents, are plants that store water in their enlarged fleshy leaves, stems, or roots. The enlargement is usually due to the greater amount of the parenchyma tissue, eg aloe vera plant. more...

Although all plants store water, succulent plants are especially adapted to store water for long periods. This allows them to survive in arid environments, where they receive little competition from other plants and less herbivory. During the day, their habitat is rather hot. However, the habitat is cooler at night allowing the succulents to respire. Often, morning dewfall helps the plants to survive: Using long hairs, that cover a large part of their surface, some succulents are able to absorb dew.

Many succulents have a waxy coating on their stems and leaves, helping them to retain moisture. Having a large internal volume for storage but minimum surface area is also important to prevent water loss. CAM photosynthesis is also a common water conservation feature found in many succulents.

Succulence is a feature due to convergent evolution and is not necessarily an indication of genetic relationship. There are succulents in many unrelated families (more or less 50, some sources note only 28). However, for some families, most members are succulent; for example the Cactaceae, Agavaceae, Aizoaceae, and Crassulaceae.

The table below shows the number of succulent species found in some families:

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