Cactus - Simple English Wikipedia, the free encyclopedia

# Cactus

### From Simple English Wikipedia, the free encyclopedia

Cactus

A cactus is a type of plant. They can live for a long time without water. Most cacti have sharp thorns. They are usually found in desert areas. Many people like to keep them at home, because they are easy to look after. The plural of cactus is cacti. They are often called a burden on the land in which they live, but that is not true. Cacti are indeed very useful to the wildlife living in desert areas. They provide both shelter from the sun and small amounts of water which desert creatures need to live. Cacti live from 25 to 300 years.

## [edit] Shapes and sizes

The flower of a Moonlight cactus.
Like many cactus fruits, the dragonfruit or pitaya (Selenicereus megalanthus) has many tiny seeds

Cacti come in a wide range of shapes and sizes. Some are short and round, while others are tall and thin. The tallest is nearly 20 metres tall, while smallest kind is only 1 centimetre across when fully grown.

Cactus flowers are often large and beautiful. They often bloom at night, and are pollinated by moths and bats. They range in size from 2 millimetres to 30 centimetres.

Cactus fruits are mostly fleshy, pleasant tasting and brightly coloured. Goats, birds, ants, mice and bats eat them and help spread the large number of tiny seeds.

## [edit] Where cacti live

Echinopsis spachiana in flower

Nearly all wild cacti live in the New World, except for one species found in Africa and Sri Lanka. It was probably spread by migrating birds carrying its seeds. cacti are well known for living in deserts, but some, such as the Christmas cactus, live in the rainforest of Brazil. They can be found in many other habitats, such as on mountains, and growing on tree branches.

## [edit] Living in the desert

Pereskia grandifolia: Pereskia is a weakly succulent cactus which also has leaves, and is thought to look like the earliest cacti. It is also one of the very few cacti to still have leaves.

Some places, such as deserts, semi-deserts and dry steppes, hardly get any water in the form of rain. Plants that live there usually have thisk, succulent leaves. The cacti, however, have succulent stems, while their leaves are reduced to spines. this helps the cactus defend itself from animals that want to eat it, and also helps stop water being lost through normal leaves, as happens with other plants.

Many species of cactus have long, sharp spines.

Thick, fleshy stems carry out photosynthesis (using sunlight to create sugar) and store water. Unlike many other succulents, the stem is the only part of a cactus where this takes place. Cacti often have a waxy coating on their stems to prevent water loss.

Saguaro cactus in Arizona, USA. This species is well known from Western films.

Most cactuses have a short growing season and stay dormant for a long time. For example, a fully-grown Saguaro cactus (Carnegiea gigantea) can absorb up to 3,000 litres of water in ten days. Only two hours after rain the cactus grows new roots, to soak up the water before it dries out. Some cacti can absorb moisture from the air. This is important in areas where it never rains but there is fog in the morning.

### [edit] Areoles

Areoles are much reduced short shoots. Every cactus has them. An areole looks like a cushion, up to 15 millimetres across. From the areole the cactus grows its flowers, spines and side-branches.

## [edit] History

| The English used in this article may not be easy for everybody to understand. You can help Wikipedia by making this page or section simpler.

The ancient Aztecs held the cactus to be very important. Cactuses can be found repeatedly in their sculpture and drawings, especially Echinocactus grusonii. Tenochtitlan (the Aztec name for Mexico City) means "place of the sacred cactus". The national arms of Mexico to this day show the eagle, snake and cactus.

From the moment of their discovery by early European explorers cactuses have aroused much interest: Christopher Columbus brought the first melocactuses to Europe. Scientists became interested in them from the 17th century. Slowly, cactuses became more and more popular. Every now and then they would become fashionable, and many people wanted to collect them and show off their new cacti.

Prickly pears (genus Opuntia) were imported into Australia in the 19th century for use as a natural fence and to establish a cochineal dye industry. The cactus spread out of control and became an unpopular weed. This invasive species cannot be eaten bybte local wildlife, and it has made 40,000 km² of land useless for farming.

From the start of the 20th century interest in cacti has increased steadily, interrupted only by the two world wars. A bad effect of this has been the digging up of many rare cacti from the wild. many species are in danger because of this. A more helpful effect has been the growth of exploration to find new species. Every year, new species of cactus are discovered.

All cacti are covered by CITES, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, and many species are fully protected by this treaty.

Some countries have a rather contradictory attitude to species protection. In Mexico, for example, to be caught in the act of digging up cactuses carries a prison sentence, but cactus habitats are destroyed for the construction of new roads and electricity lines.

## [edit] Uses

| The English used in this article may not be easy for everybody to understand. You can help Wikipedia by making this page or section simpler.

Echinocactus grusonii is a popular species in cultivation

The Native Americans of North America use many cacti in rituals. Today, besides their use as food (jam, fruit, vegetables), their main use is as a host for the cochineal insect, which produces a red dye(carmine), which is used in food colouring or high-quality lipsticks. In South America The wood of dead pillar cacti are used for construction. Some cacti also have medical uses.

Cacti, cultivated by people worldwide, are a familiar sight as potted plants, houseplants or in ornamental gardens in warmer climates. They often form part of dry gardens in arid regions, or raised rockeries. Some countries, such as Australia, have water restrictions in many cities, so drought-resistant plants are increasing in popularity. Numerous species have entered widespread cultivation, including members of Echinopsis, Mammillaria and Cereus among others. Some, such as the Golden Barrel Cactus, Echinocactus grusonii, are prominent in garden design. Cacti are commonly used for fencing material where there is a lack of either natural resources or financial means to construct a permanent fence. This is often seen in arid and warm climates, such as the Masai Mara in Kenya. This is known as a cactus fence.

As well as garden plants, many cacti have important commercial uses; some cacti bear edible fruit, such as the prickly pear and Hylocereus, which produces Dragon fruit or Pitaya.

Wikimedia Commons has media related to:
Cactus
Retrieved from "http://simple.wikipedia.org../../../c/a/c/Cactus.html"

Categories: Complex pages | Plants

##### Views

- Article
- Talk
- Newest version

##### Search

##### In other languages

- العربية
- Bân-lâm-gú
- বাংলা
- བོད་ཡིག
- Български
- Català
- Česky
- Dansk
- Deutsch
- English
- Español
- Français
- Galego
- Hrvatski
- Bahasa Indonesia
- Italiano
- עברית
- Lietuvių
- Nederlands
- 日本語
- ‪Norsk (bokmål)‬
- Polski
- Português
- Русский
- Suomi
- Svenska
- Tiếng Việt
- 中文