Carex

Some plants look like grass.

These plants are called true sedges. They grow in many places. Many grow in wet lands. Some grow in cold, snowy spots. Their stalks are often shaped like a triangle. The leaves can be green, red, or brown.

These plants have tiny flowers. The flowers grow in small groups. Some people use these plants for food. Others use them to make baskets. They are very useful plants.

Carex are plants known as true sedges. They belong to a huge group. There are over 2,000 different kinds.

Most sedges love wet places. You can find them in marshes or near streams. Some live in very cold areas like the tundra. Their stalks are often shaped like a triangle. The leaves can be green, red, or brown. Some leaves are long and flat. Other leaves are thin like hair.

These plants have tiny flowers. The flowers grow in groups called spikes. Most Carex plants have both male and female flowers. A special part called a perigynium surrounds the female flower. This part looks like a small bottle. It often has a tiny beak at the top. Inside this bottle, a single seed grows.

Many people use Carex. Native groups have used them for a long time. Some used the roots to weave baskets. Others used the leaves to make mats. Some even used dried plants to keep feet warm in boots. Today, people use them in gardens to shade the ground.

Carex is a huge group of plants known as true sedges. There are over 2,000 different species in this group. They belong to a plant family called Cyperaceae. Scientists who study these plants are called caricologists.

These plants are very important in nature. Many live in wet places like marshes or bogs. You can find them near ponds and stream banks. They also grow in very cold places like the arctic tundra. Some even live in mountain areas called alpine tundra.

Most Carex plants have a very specific way they grow. Their main stalk is called a culm. This stalk is usually straight and not branched. If you look closely, the stalk is often shaped like a triangle. The leaves have a long part called a blade. They also have a sheath that wraps around the stalk. Some leaves are wide and flat. Other leaves might be thin like hair.

The flowers of the Carex are quite small. They grow in groups called spikes. These spikes join together to make a larger flower group. Most species are monoecious. This means each flower is either male or female. Some species have male flowers on top and female flowers on the bottom. A special part called a perigynium surrounds the female flower. This part looks like a tiny bottle. It often has a small beak at the tip.

Humans have learned a lot about Carex over time. Carl Linnaeus first named this group in 1753. He wrote about them in a book called Species Plantarum. Since then, people have found many different types. Some scientists divide them into four main groups called subgenera. One large group is called Carex subg. Carex. It has about 1,450 different species. Another group is called subg. Vignea, which has 350 species.

Many people use Carex in their daily lives. Native American groups have used these plants for a long time. The Ohlone and Pomo people used roots to weave baskets. The Klamath people used the leaves to make mats. Some groups used dried plants to keep their feet warm in boots. This is called sennegrass. Today, gardeners use special types of Carex in shady gardens. They can even be used to help fix wild lands.

Carex is a massive genus of flowering plants. It contains over 2,000 different species. These plants belong to the family Cyperaceae. Most people call these plants sedges. However, scientists call the Carex group "true sedges" to tell them apart from other sedges. The scientific study of these plants is called caricology.

These plants are vital to many ecosystems. They are dominant in arctic and alpine tundra. They also thrive in wetlands like marshes, bogs, and peatlands. They can grow in water up to certain depths in riparian zones or ditches.

To understand how a Carex plant grows, look at its structure. Most species are perennial, meaning they live for many years. They often grow from rhizomes, stolons, or short rootstocks. The main flower-bearing stalk is called a culm. This culm is usually unbranched and stands straight up. A key feature is that the culm is often triangular in section. The leaves consist of a blade and a sheath. The sheath wraps around the stalk, while the blade extends outward. Blades can be flat, folded, or even hair-like.

The reproductive process of Carex involves complex flower arrangements. The flowers are small and grow in clusters called spikes. These spikes join together to form a larger inflorescence. Most species are monoecious, meaning a single plant has both male and female flowers. In these plants, each individual flower is either staminate (male) or pistillate (female). Some species are dioecious, meaning male and female flowers are on separate plants. The arrangement can vary greatly. Some plants have female flowers on lower spikes and male flowers on upper spikes. Others are androgynous, with male flowers above female ones. Some are gynecandrous, with female flowers above male ones.

A defining feature of the genus is the perigynium. This is a bottle-shaped structure that surrounds each female flower. It is a modified prophyll, or a specialized leaf-like part. The perigynium often ends in a beak called a rostrum. This beak might be bifid, which means it is divided into two teeth. Inside this protective sac, the fruit grows. The fruit is an achene, which is a dry, one-seeded nut. This fruit is indehiscent, meaning it does not split open at maturity. The shape and hairs, or vestiture, of the perigynium help scientists identify different species.

The history of Carex classification began with Carl Linnaeus. He established the genus in his 1753 work, *Species Plantarum*. Since then, scientists have debated how to group these many species. One famous researcher, Georg Kükenthal, divided them into four subgenera. He used the arrangement of flowers to make these groups. These included *Carex*, *Vignea*, *Indocarex*, and *Primocarex*. Today, the genus is divided into about four subgenera. For example, *Carex subg. Carex* is the largest with 1,450 species. *Carex subg. Vignea* contains about 350 species. *Carex subg. Psyllophora* has about 70 species. *Carex subg. Vigneastra* has about 100 species.

Carex is also famous for its dynamic chromosome evolution. This means its genetic makeup changes very quickly. Chromosome numbers in Carex range from n = 6 to n = 66. This is a massive range for flowering plants. Over 100 species show variation in chromosome numbers within a single species. Sometimes, different populations of the same species differ by up to 10 chromosomes. Scientists have successfully sequenced the genomes of *Carex kokanica*, *Carex parvula*, and *Carex littledalei*. Fossil evidence also exists, such as fossil fruits found in Denmark from the middle Miocene period.

Humans have used Carex for many different purposes throughout history. Many Native American groups used the plants for survival. The Ohlone, Pomo, and Yuki people used roots for basketry. The Klamath and Montana people used leaves to weave mats. Some groups, like the Blackfoot, used Carex in moccasins for warmth. A mix of dried species is called sennegrass. This was used as thermal insulation in footwear. Even early explorers used it, such as during the 1911 South Pole expedition. Today, people use Carex in gardens as ornamental plants. They are also used in restoration projects to help wild lands thrive.