Araucaria araucana

This tree is called the monkey-puzzle tree.

Its leaves are thick and sharp. They look like scales. These leaves can stay on the tree for 24 years.

The tree has thick bark. This helps it stay safe from fire. It grows in Chile and Argentina.

Small mice help the tree grow. They bury the seeds in the ground. This helps new trees start to grow.

Some people eat the seeds. They taste like large nuts. It is a very special tree.

The monkey-puzzle tree is a very special tree.

It grows in Chile and Argentina. This tree is the national tree of Chile. It is also the national tree of Neuquén in Argentina.

The leaves are thick and sharp. They look like scales. These leaves stay on the tree for 24 years. The tree has very thick bark. This bark can be 15 cm thick. It helps the tree survive forest fires.

Male and female cones grow on separate trees. This is called being dioecious. The wind helps move pollen from male cones to female cones. The female cones hold about 200 seeds. These seeds are called piñones. They taste like large pine nuts. People in South America eat them.

Small animals help new trees grow. The long-haired grass mouse is very important. This mouse buries seeds in the ground. This helps the seeds start to grow. Parakeets also help spread the seeds.

Today, the tree is endangered. This means there are not many left. Logging and forest fires are big threats. Also, some animals eat too many seeds. This stops new trees from growing.

The Araucaria araucana is a very special evergreen tree.

People call it many names, like the monkey-puzzle or the Chile pine. It is the national tree of Chile and the Argentine province of Neuquén. These trees grow in the Andes mountains of central and southern Chile and western Argentina. They are the hardiest species in their group. Sadly, the IUCN listed them as Endangered in 2013. This happened because of logging, forest fires, and grazing by animals.

This tree has a very unique way of growing. Young trees look like a pyramid or a cone. As they get older, they grow into a shape like an umbrella. The leaves are thick, tough, and triangular with sharp edges. These leaves can stay alive on the branches for up to 24 years. The tree is dioecious, which means male and female cones grow on different trees. Wind carries pollen from the oblong male cones to the female cones.

The female cones are large and round. They hold about 200 seeds that look like nuts. These cones fall apart when they are ready to release the seeds.

Humans have studied this tree for a long time. A Spaniard named Francisco Dendariarena first mentioned it in 1780. Later, J.I. Molina named it Pinus araucana in 1782. In 1873, a scientist named Koch gave it the name we use today. In the 1800s, William Lobb collected many seeds for English nurseries. He found them in the Araucanía Region of Chile.

Today, scientists like Chris Page study how these trees can grow in new places. They have even planted them in old clay pits in England.

There are many interesting facts about how the tree survives. The bark can be as thick as 15 cm. This thick bark might help the tree survive forest fires. The tree loves volcanic soil that drains water well. It lives at altitudes between 500 and 1,800 meters.

It can even live in temperatures as low as -10°C. The seeds are called piñones and are edible. They are similar to large pine nuts. Indigenous people in Chile and Argentina harvest them to eat. They have used these seeds for a very long time.

Nature works together to help the tree spread. Small animals are very important for the tree's life. The long-haired grass mouse buries seeds in good spots for growing. This helps the seeds turn into new trees. The austral parakeet also helps move seeds to new areas.

This is helpful after big volcanic eruptions. Even the name "monkey-puzzle" comes from a funny story. A man named Charles Austin saw the tree in a garden. He said it would puzzle a monkey to climb it! This name stuck and is used by people all over the world.

The *Araucaria araucana* is a remarkable evergreen conifer. It is known by many names, including the pehuen, the Chile pine, and the monkey-puzzle. This tree is the national tree of Chile and the Argentine province of Neuquén. It belongs to the Araucariaceae family. It is considered the hardiest species within the *Araucaria* genus. Today, the tree faces significant challenges. The IUCN changed its conservation status to Endangered in 2013. This change occurred because logging, forest fires, and grazing have caused populations to shrink.

The tree has a very specific way of growing and changing over time. Juvenile trees start with a broadly pyramidal or conical shape. As they reach maturity, they develop a distinctive umbrella form. The leaves are thick, tough, and scale-like. They are triangular and broad at the base with sharp edges and tips. These leaves are incredibly long-lived. They can remain attached and stay alive for up to 24 years. This allows them to cover almost all parts of the tree, except for the oldest branches.

Reproduction in *Araucaria araucana* involves a process called being dioecious. This means that male and female cones grow on separate individual trees. The male cones are oblong and shaped like a cucumber. These cones expand during pollen release. The tree relies on wind pollination to move pollen from male to female trees. The female cones are globose, which means they are large and round. These cones mature in the autumn, about 18 months after pollination. Each large cone can hold approximately 200 seeds. When the cones reach maturity, they disintegrate to release long, nut-like seeds.

Nature provides several ways for these seeds to spread and grow. The species is a masting species, meaning it produces large amounts of seeds at certain intervals. This strategy helps ensure some seeds survive by overwhelming predators. Rodents are vital for this process. The long-haired grass mouse, *Abrothrix longipilis*, is the most important animal for seed dispersal. Unlike other animals, this mouse buries the seeds whole in locations good for germination. The austral parakeet also helps disperse seeds. This is especially important after large ecological disturbances like volcanic activity. Parakeets can carry seeds far away from affected territories.

The history of how we name and study this tree is quite long. The Spaniard Francisco Dendariarena first mentioned the tree in 1780. In 1782, J.I. Molina named it *Pinus araucana*. Later, in 1873, the scientist Koch published the name *Araucaria araucana*. This name comes from the native Araucanians. The Pehuenches people live in the Andes and owe their name to their diet. They call the tree "pewen," which means *Araucaria*. The English name "monkey-puzzle" comes from a 19th-century observation. A man named Charles Austin saw a specimen in a garden. He remarked that it would puzzle a monkey to climb it.

This tree is very strong and can survive in tough environments. Its bark can grow up to 15 cm thick. This thick bark may be an adaptation to help the tree survive wildfires. It grows on the lower slopes of the Andes between 500 and 1,800 meters. The tree prefers well-drained, slightly acidic, volcanic soil. It can tolerate temperatures as low as -10°C. Because it is so hardy, it is grown in many places. You can find it in western Europe, North America, New Zealand, and Australia. It can even handle coastal salt spray, though it does not like air pollution.

Humans have many different connections to the *Araucaria araucana*. The seeds, called piñones, are edible and taste like large pine nuts. Indigenous peoples in Argentina and Chile have harvested them for a long time. In the past, the wood was valued for its long, straight trunks. It was even used for railway sleepers in Chile. However, because the trees are now rare, their wood is rarely used. Today, the tree is protected under Appendix I of CITES. This means international trade of the tree is strictly regulated. Scientists continue to study the tree to help it grow in new places. For example, researchers have planted them in old clay pits in England to study regreening.