Tussock grasses or bunch grasses are a group of grass species in the family Poaceae. They usually grow as singular plants in clumps, tufts, hummocks, or bunches, rather than forming a sod or lawn, in meadows, grasslands, and prairies. As perennial plants, most species live more than one season. Tussock grasses are often found as forage in pastures and ornamental grasses in gardens.^[1][2][3]

Many species have long roots that may reach 2 meters (6.6 ft) or more into the soil, which can aid slope stabilization, erosion control, and soil porosity for precipitation absorption. Also, their roots can reach moisture more deeply than other grasses and annual plants during seasonal or climatic droughts. The plants provide habitat and food for insects (including Lepidoptera), birds, small animals and larger herbivores, and support beneficial soil mycorrhiza. The leaves supply material, such as for basket weaving, for indigenous peoples and contemporary artists.

Tussock and bunch grasses occur in almost any habitat where other grasses are found, including: grasslands, savannas and prairies, wetlands and estuaries, riparian zones, shrublands and scrublands, woodlands and forests, montane and alpine zones, tundra and dunes, and deserts.

Fire resistance

In western North American wildfires, bunch grasses tend to smolder and not ignite into flames, unlike invasive species of annual grasses that contribute to a fire's spreading.^[4]

Genera

Examples:

• Brachypodium
• Calamagrostis
• Chionochloa
• Deschampsia
• Festuca
• Heteropogon (tropical climates)
• Leymus
• Melica
• Muhlenbergia
• Nassella
• Stipa
• Triodia, formerly Plectrachne (Australia)

Species

Australia

• Gymnoschoenus sphaerocephalus – button grass
• Joycea pallida – red anther wallaby grass
• Poa labillardierei – common tussock-grass
• Poa sieberiana – grey tussock-grass

New Zealand

• Chionochloa australis – carpet grass
• Chionochloa flavescens – snow tussock
• Chionochloa oreophila – snow-patch grass
• Chionochloa rubra – red tussock
• Festuca novaezelandiae – fescue tussock or hard tussock
• Poa cita – silver tussock
• Poa colensoi – blue tussock
• Poa foliosa – muttonbird poa

North America

Bunch grasses:^[5]

• Aristida purpurea – purple three-awn
• Bouteloua gracilis – blue grama
• Calamagrostis foliosa – leafy reedgrass (endemic to California)
• Calamagrostis nutkaensis – Pacific reedgrass
• Calamagrostis purpurascens – purple reedgrass
• Danthonia californica – California oatgrass
• Eriophorum vaginatum – hare's-tail cottongrass
• Festuca californica – California fescue
• Festuca idahoensis – Idaho fescue
• Festuca rubra – red fescue
• Koeleria macrantha – junegrass
• Leymus condensatus – giant wildrye
• Melica californica – California melic
• Melica imperfecta – smallflower melic
• Muhlenbergia rigens – deer grass
• Nassella lepida – foothill needlegrass
• Nassella pulchra – purple needlegrass (the state grass of California)
• Poa secunda – pine bluegrass
• Sporobolus heterolepis – prairie dropseed
• Sporobolus virginicus – salt couch grass
• Tripsacum dactyloides – eastern gamagrass

South America

• Deschampsia cespitosa – tufted hair-grass (up through North America)
• Nassella trichotoma – serrated tussock (common pasture weed in Australia)
• Poa flabellata – tussac grass (synonyms: Parodiochloa flabellata, Festuca flabellata, Dactylis caespitosa)

Africa

• Heteropogon contortus – perennial tussock grass (to Asia, Australasia, Oceania)

Europe

• Ampelodesmos mauritanicus – rope grass
• Brachypodium sylvaticum – false-brome
• Molinia caerulea – purple moor grass (to west Asia and north Africa)