Choke vs Common Silver Hairgrass

Epichloe typhina compared with Aira caryophyllea

Key Differences

Choke is Not Evaluated while Common Silver Hairgrass is Endangered.

Taxonomic Classification

Rank	Choke	Common Silver Hairgrass
Kingdom	Fungi (Fungi)	Plantae (Plants)
Phylum	Ascomycota (Sac Fungi)	Magnoliophyta (Flowering Plants)
Class	Sordariomycetes (Sordariomycetes)	Liliopsida (Monocots)
Order	Hypocreales (Hypocreales)	Poales (Grasses)
Family	Clavicipitaceae	Poaceae (Grass Family)
Genus	Epichloe	Aira
Species	Epichloe typhina	Aira caryophyllea

Conservation Status

Choke

NE — Not Evaluated

Common Silver Hairgrass

EN — Endangered

Physical Characteristics

Attribute	Choke	Common Silver Hairgrass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Choke

Habitat

Native to North America, inhabiting ecosystems characteristic of the region.

Range

Found in United States.

Common Silver Hairgrass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical grasslands and savannas, and flooded grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (Cameroon), Asia (Japan, South Korea), Europe (6 countries), North America (4 countries), Oceania and the Pacific (Australia), and South America (4 countries). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Choke

Choke (Epichloe typhina) is an endophytic and pathogenic fungus in the family Clavicipitaceae, phylum Ascomycota, that colonises the tissues of various cool-season grasses (Poaceae) across Europe and North America. The name refers to the disease it causes — infected grass tillers are typically 'choked' (prevented from flowering) when the fungus produces a dense, white to cream-coloured, stromata (a compact fungal structure) that surrounds the flowering stem before it can emerge, suppressing seed production. Epichloe species exist along a mutualism-parasitism continuum; some strains are biotrophic endophytes living almost entirely within grass tissues without obvious symptoms and conferring benefits to the host such as increased drought resistance and deterrence of herbivores through alkaloid production, while others — including E. typhina — are more parasitic in nature, sterilising infected host tillers. The fungus spreads via airborne ascospores produced on its stroma that infect new host plants. Related Epichloe/Neotyphodium endophytes are of great practical importance to agriculture as they produce ergot alkaloids and other compounds that can cause toxicosis in livestock grazing infected pasture grasses. As a fungal pathogen/endophyte rather than a wildlife species, it is Not Evaluated by the IUCN.

Common Silver Hairgrass

<em>Aira caryophyllea</em>, commonly known as Common Silver Hairgrass, is a slender annual grass belonging to the family Poaceae within the order Poales. This delicate grass is currently classified as Endangered on the IUCN Red List, reflecting significant conservation concern despite its historically broad distribution. It is typically found across a remarkable diversity of biome types, including tropical and subtropical moist broadleaf forests, grasslands, savannas, and flooded habitats, demonstrating notable ecological versatility. Its geographic range spans multiple continents, with documented populations in Africa (Cameroon), Asia (Japan, South Korea), Europe, North America, Australia, and South America. As an annual grass, it completes its life cycle within a single growing season, reproducing via wind-dispersed seeds. The inflorescence typically bears silvery, shimmering spikelets that give the species its common name. Biological traits such as average lifespan, body dimensions, and dietary specifics follow typical patterns for annual grasses — drawing nutrients from soil through root absorption rather than consuming other organisms. The endangered status suggests populations may be declining due to habitat loss, land-use change, or invasive species pressure across parts of its range.