What is the Poaceae family?

The Poaceae, also known as the grass family, is a highly abundant and significant family of monocotyledonous flowering plants in the order Poales. As the world's single most important source of food, Poaceae ranks among the top five families of flowering plants in terms of species number. Grasses are adaptable and can be found on all continents, growing in diverse habitats ranging from deserts to freshwater and marine environments, and at almost all elevations. Plant communities dominated by grasses make up approximately 24% of the Earth’s vegetation. There are about 10,000 grass species, with nearly 800 genera, distributed across seven major groups. Grasses have various means of reproduction, and their success results from their tolerance of grazing herbivores and fire, and their versatility in photosynthesis.

What types of plants belong to the Poaceae family?

The Poaceae family, also known as the grass family, is a highly diverse group of monocotyledonous flowering plants with approximately 10,000 species. Grasses are the world’s single most important source of food and are among the most abundant plants on Earth, growing on all continents in varied habitats. Examples of plants in the Poaceae family include: * Cereal crops: Rice ( Oryza sativa ), corn (maize; Zea mays ), and wheat ( Triticum aestivum ) * Other grasses: Sugarcane ( Saccharum officinarum ), bamboo (subfamily Bambusoideae), bluegrass ( Poa annua ) and barnyard grass ( Echinochloa crus-galli )

Where can Poaceae plants be found growing?

Poaceae , also known as the grass family, is a group of flowering plants that stands out as the world's most significant food source. Grasses are adaptable plants found across the globe, thriving on every continent, excluding only the highest elevations. They inhabit diverse environments, from deserts to freshwater and marine habitats. Grasses are so prevalent that they cover approximately 24% of the Earth’s vegetation. With around 10,000 species, many grasses are limited to a single continent. However, some, like Phragmites australis , have a wide geographic range, growing between latitudes 70° N and 40° S. Grasses can be found in various plant communities, including freshwater and saltwater marshes, tundras, meadows, and disturbed habitats. They have adapted to environmental extremes, from cold regions to equatorial heat, and from aquatic habitats to deserts.

Why are Poaceae plants important to humans and animals?

The Poaceae family, also known as grasses, is the single most important source of food for humans. They are a primary food source; up to 70% of agricultural land is used for growing grasses, which provide over 50% of the world's calories. Grasses such as sugarcane, wheat, rice, and corn are well-known crops. Grasses are also used to feed livestock and poultry. Beyond food, grasses like bamboo provide building materials, paper, and various household items. Additionally, grasses play a crucial role in erosion control and as turf.

What are some common features of Poaceae plants?

Poaceae, also known as the grass family, is a highly abundant and significant plant family found across the globe in varied habitats. Key traits include: * Fibrous root systems instead of a taproot * Herbaceous or woody stems, called culms, that range in size based on climate and species * Leaves borne singly at the nodes, arranged in two vertical ranks * Parallel veins and specialized cells containing silica bodies in the outermost layer of grass leaves * Flowers adapted for wind-pollination * Grains, also called caryopses, in which the fruit wall adheres completely to the single seed Grasses exhibit remarkable tolerance to grazing and fire, coupled with diverse reproductive strategies and photosynthetic versatility, contributing to their ecological success.

How do Poaceae plants reproduce and spread in nature?

Poaceae, or grasses, reproduce through cross-pollination, self-fertilization, and asexually. Cross-pollination is most common, but self-fertilization helps single plants reproduce after dispersal and preserves successful gene combinations. Asexual reproduction occurs through apomixis, where seeds develop without fertilization, creating clones of the parent plant. Many grasses also spread via vegetative parts like rhizomes (underground stems) and stolons (aboveground shoots). These adaptations, along with tolerance to grazing and fire, contribute to the success and wide distribution of grasses. Wind also aids pollination.

Poaceae

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Dense cluster of Kentucky bluegrass (Poa pratensis) plants with slender green stems and fine, feathery seed heads.

Poaceae

plant family

Also known as: Gramineae, grass family

Written by

Christopher S. Campbell

Fact-checked by

Britannica Editors

Last updated

Oct. 2, 2026 •History

Top Questions

What is the Poaceae family?
The Poaceae, also known as the grass family, is a highly abundant and significant family of monocotyledonous flowering plants in the order Poales. As the world's single most important source of food, Poaceae ranks among the top five families of flowering plants in terms of species number.

Grasses are adaptable and can be found on all continents, growing in diverse habitats ranging from deserts to freshwater and marine environments, and at almost all elevations. Plant communities dominated by grasses make up approximately 24% of the Earth’s vegetation. There are about 10,000 grass species, with nearly 800 genera, distributed across seven major groups. Grasses have various means of reproduction, and their success results from their tolerance of grazing herbivores and fire, and their versatility in photosynthesis.
2 Britannica Sources
1. Poaceae
2. Poales: Grass group
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What types of plants belong to the Poaceae family?
The Poaceae family, also known as the grass family, is a highly diverse group of monocotyledonous flowering plants with approximately 10,000 species. Grasses are the world’s single most important source of food and are among the most abundant plants on Earth, growing on all continents in varied habitats.

Examples of plants in the Poaceae family include:
* Cereal crops: Rice (Oryza sativa), corn (maize; Zea mays), and wheat (Triticum aestivum)
* Other grasses: Sugarcane (Saccharum officinarum), bamboo (subfamily Bambusoideae), bluegrass (Poa annua) and barnyard grass (Echinochloa crus-galli)
4 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Where can Poaceae plants be found growing?
Poaceae, also known as the grass family, is a group of flowering plants that stands out as the world's most significant food source. Grasses are adaptable plants found across the globe, thriving on every continent, excluding only the highest elevations. They inhabit diverse environments, from deserts to freshwater and marine habitats. Grasses are so prevalent that they cover approximately 24% of the Earth’s vegetation.

With around 10,000 species, many grasses are limited to a single continent. However, some, like Phragmites australis, have a wide geographic range, growing between latitudes 70° N and 40° S. Grasses can be found in various plant communities, including freshwater and saltwater marshes, tundras, meadows, and disturbed habitats. They have adapted to environmental extremes, from cold regions to equatorial heat, and from aquatic habitats to deserts.
4 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
Why are Poaceae plants important to humans and animals?
The Poaceae family, also known as grasses, is the single most important source of food for humans. They are a primary food source; up to 70% of agricultural land is used for growing grasses, which provide over 50% of the world's calories.

Grasses such as sugarcane, wheat, rice, and corn are well-known crops. Grasses are also used to feed livestock and poultry. Beyond food, grasses like bamboo provide building materials, paper, and various household items. Additionally, grasses play a crucial role in erosion control and as turf.
2 Britannica Sources
1. Poaceae: Economic and ecological importance
2. list of economically important members of the family Poaceae
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What are some common features of Poaceae plants?
Poaceae, also known as the grass family, is a highly abundant and significant plant family found across the globe in varied habitats.

Key traits include:
* Fibrous root systems instead of a taproot
* Herbaceous or woody stems, called culms, that range in size based on climate and species
* Leaves borne singly at the nodes, arranged in two vertical ranks
* Parallel veins and specialized cells containing silica bodies in the outermost layer of grass leaves
* Flowers adapted for wind-pollination
* Grains, also called caryopses, in which the fruit wall adheres completely to the single seed

Grasses exhibit remarkable tolerance to grazing and fire, coupled with diverse reproductive strategies and photosynthetic versatility, contributing to their ecological success.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How do Poaceae plants reproduce and spread in nature?
Poaceae, or grasses, reproduce through cross-pollination, self-fertilization, and asexually. Cross-pollination is most common, but self-fertilization helps single plants reproduce after dispersal and preserves successful gene combinations.

Asexual reproduction occurs through apomixis, where seeds develop without fertilization, creating clones of the parent plant. Many grasses also spread via vegetative parts like rhizomes (underground stems) and stolons (aboveground shoots). These adaptations, along with tolerance to grazing and fire, contribute to the success and wide distribution of grasses. Wind also aids pollination.
4 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Poaceae, grass family of monocotyledonous flowering plants, a division of the order Poales. The Poaceae are the world’s single most important source of food. They rank among the top five families of flowering plants in terms of the number of species, but they are clearly the most abundant and important family of the Earth’s flora. They grow on all continents, in desert to freshwater and marine habitats, and at all but the highest elevations. Plant communities dominated by grasses account for about 24 percent of the Earth’s vegetation.