Glossary of Common Terms
Cactus
A specific family of plants (Cactaceae) native to the new world containing
approximately 2,500 species (about 1/4 of all succulent plants).
All Cactus are succulent and are identified by their leaves that
have been modified into 'spines'.
Caudex
A storage organ on some root succulents that grows at ground level
or below. This is really part of the stem of the plant and often times
growers raise this out of the ground even more than in nature to show
off the attractive stem/root as a feature of the plant. It generally
increases in size as the plant grows/get older.
Convergent
Evolution
When two or more otherwise unrelated plants from different geologic
locations evolve similar characteristics to adapt to a similar set of
conditions present. There are a number of such examples among the succulent
plants of the world such as some of the columnar cactus of the Americas
and some of the Euphorbias of Africa and Madagascar. See What
is a Succulent? for more information and pictures of examples.
Crest
A mutation that affects the growing tip of the plant that forms a
long line rather than a single point. It is unknown exactly why this
occurs but has been noted in almost every type of plant. Often this mutation
inhibits flowering and therefore natural reproduction of the plant.
Succulent
A succulent is a plant that stores water for times when water is not
available to it. Succulent plants are generally found in arid environments
such as deserts and semi-deserts. However, they can also be found in
areas where the annual rainfall is high but not reliable (for instance
most of the annual rainfall comes once or twice a year in quick bursts).
Succulent plants have adapted several different ways to store and conserve
water for times of need.; There are stem succulents that store water
in the stem of the plant... like most of the familiar local cacti.
There are root succulents such as: where water is stored in the roots
or a caudex, examples are: peniocereus greggii (queen
of the night), and the adeniums and pachypodiums (Madagascar palm).
Finally there are leaf succulents such as the agaves and aloes that
store water in a succulent leaf.