clouded drab vs Common Silver Hairgrass

Orthosia incerta compared with Aira caryophyllea

Key Differences

clouded drab is Least Concern while Common Silver Hairgrass is Endangered.

Taxonomic Classification

Rank	clouded drab	Common Silver Hairgrass
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Liliopsida (Monocots)
Order	Lepidoptera (Butterflies & Moths)	Poales (Grasses)
Family	Noctuidae	Poaceae (Grass Family)
Genus	Orthosia	Aira
Species	Orthosia incerta	Aira caryophyllea

Conservation Status

clouded drab

LC — Least Concern

Common Silver Hairgrass

EN — Endangered

Physical Characteristics

Attribute	clouded drab	Common Silver Hairgrass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

clouded drab

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

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.

clouded drab

The clouded drab (Orthosia incerta) is a noctuid moth in the family Noctuidae and one of the characteristic early-spring moths of temperate Europe and western Asia, flying from February to April when most other moth species are inactive. The adult wingspan measures approximately 35–42 mm with variable forewings ranging from pale greyish-buff through warm reddish-brown to dark grey-brown, bearing subtle cross-lines, stigmata, and the clouded, diffuse shading that gives the species its common name. The variability of the clouded drab has historically created confusion with related Orthosia species. Adults emerge early in the year, taking nectar from sallow catkins and other early-spring flowers. Larvae feed on the foliage of deciduous trees and shrubs including oak, hawthorn, birch, and hazel in woodland, scrub, and hedgerow habitats. The clouded drab is one of the more numerous and widespread spring moths in Britain and northern Europe, routinely recorded at light traps and regarded as an indicator of woodland health. The early flight season makes it an important pollinator of early-flowering trees and shrubs in temperate woodland systems.

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.