The name Cacti or Cactus has been adopted by the masses as the
universal term to describe succulent plants. I have heard the term
used to describe a varied range of plants from Euphorbias
to Fouquierias (Ocotillo) to Agaves, Yuccas,
By including what are not cacti, CactiGuide.com can be a more
useful guide through the process of elimination. The table below
lists examples of other succulents that resemble cacti but are not.
This should give beginners a good start. There are exceptions to
every rule and this is so true with the features used to identify
cacti. Those who happen across such an exception should prepare
to do some extensive research and be patient. Some of the features
that separate cacti from other genera are:
>>>For a fun way to learn more, try the Cactus or Succulent Quiz!
||Flowers, branches, spines sprout from these- no
other plant has this feature.
||Perhaps the most familiar feature of cacti, spines
can vary greatly in appearance, shape, size, and color. Spines
are not thorns.
||Flowers are not unique to cacti, but cacti flowers
are unique. Cacti flowers are typically quite spectacular and
very complex. Unfortunately this field mark is only helpful,
of course, if the plant happens to be blooming.
||Most cacti do not have leaves, however, some do.
Pay special attention to the presence or absence of leaves.
||All cacti are native to the Americas and surrounding
islands. With one exception -Rhipsalis baccifera. Although,
world wide cultivation has made this less helpful for identification.
|*A large amount of information is
available on this subject, see Sources
for further study.
Typically large rosettes with long flat pointed leaves that
terminate in an extremely sharp point. Commonly referred to
as a Century Plant, Agaves can be found growing in many places
that cacti grow. Agaves bloom once every 7-20 years or so
and afterwards the main plant dies and is succeeded by off
shoots or new plants at the flower tips.
|Aloe Vera is a name that everyone
has heard before. Most people have used it to aid in healing
a cut or a bad sunburn. Many lotions and soaps also contain
Aloe. It seems people don't mistake Aloe Vera for a cactus,
since they know it simply as "Aloe Vera", however,
there are over 240 species of Aloe many of which are commonly
misnamed "Cacti". Aloes occur naturally in the dry
regions of Africa, Asia, Europe, and the Americas.
|Most Echeverias are small rosettes
that grow along rocky hillsides from the Southern United States
south to Northern South America. A common name for this plant
is "Hen and Chicks" and is widely cultivated in gardens
and greenhouses around the world. Check to make sure that the
cactus plant you are having a hard time identifying isn't an
|Perhaps no other taxon is more commonly
confused with true cacti than that of Euphorbia. Some Euphorbias
look more like a stereotypical cactus than even some cacti species.
Euphorbias can be found all over the world, but most originated
in Africa. If you cut a Euphorbia, it will secrete a sticky,
milky-white fluid. This fluid contains latex. Flowers of Euphorbias
are typically small nondescript buttons with no sepals or petals.
Many Euphorbias also have thorns, making them appear even more
similar to cacti. Upon closer inspection, however, one can easily
see that these are not a separate spine arising from an areole
like that of a true cacti.
|Another African native, the genus
Lampranthus (Ice Plant) consists of a large number of species
used very commonly as ground cover in warmer climates. These
plants feature succulent leaves and spectacular flowers. Ironically
Ice Plant stems most closely resemble the cactus species Rhipsalis,
which exhibit the least exciting, relatively smallest flowers
of the Cactus Family.
|Fouquieria is the genus commonly
known as Ocotillo. Native to the Southwest United States and
Mexico, Ocotillo grows along with cacti in these regions and
even in areas that are too hot and dry for cacti. Ocotillo is
confused with cacti because of where it grows and also because
of its thorns. Ocotillo may or may not have leaves at any given
time throughout the year. It may shed and re-grow leaves as
much as seven times in one year.
|The top of a pineapple more closely
resembles a Yucca than perhaps any other familiar object. Yuccas
grow throughout North America in many of the places that cacti
do. The stiff leaves of a Yucca resemble blades of grass arranged
in a rosette, only they are very rigid with needle-sharp tips.
Some Yuccas grow right on the ground while others have treelike
|These little "living stones" are
another succulent often mistakenly referred to as a cactus. These unique
and interesting plants hail from Southern Africa. They vary quite a bit
in color and markings, but are all very similar in overal size and shape.
Like the one shown here, they feature two stone-like leaves joined at a
fissure. They range in size from 2 to 4 inches across.
|Still a different Southern Africa native
that has many people fooled by its succulent stems. Remembering that all
cacti are succulents, but not all succulents are cacti, we can examine
Stapelia and discover that they lack the qualifications of a true cacti.
These plants are sometimes referred to as Star of David as the flowers
resemble a Jewish star. If you're around this plant when its flowering
you'll notice that it gives off an unpleasant odor which attracts flys