Common Fieldcap vs Onion Downy Mildew

Agrocybe pediades compared with Peronospora destructor

Key Differences

Common Fieldcap is Least Concern while Onion Downy Mildew is Not Evaluated.

Taxonomic Classification

Rank	Common Fieldcap	Onion Downy Mildew
Kingdom	Fungi (Fungi)	Chromista (Chromista)
Phylum	Basidiomycota (Club Fungi)	Oomycota (Oomycetes)
Class	Agaricomycetes (Mushrooms)	Peronosporea (Peronosporea)
Order	Agaricales (Gilled Mushrooms)	Peronosporales (Peronosporales)
Family	Strophariaceae	Peronosporaceae
Genus	Agrocybe	Peronospora
Species	Agrocybe pediades	Peronospora destructor

Conservation Status

Common Fieldcap

LC — Least Concern

Onion Downy Mildew

NE — Not Evaluated

Physical Characteristics

Attribute	Common Fieldcap	Onion Downy Mildew
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Fieldcap

Habitat

Typically found in forest floors, decomposing wood, and soil ecosystems.

Range

Found across Europe (5 countries) and North America (United States).

Onion Downy Mildew

Habitat

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

Range

Widely distributed across Europe (4 countries), North America (United States), and South America (Brazil).

Common Fieldcap

The Common Fieldcap (<em>Agrocybe pediades</em>) is a saprotrophic fungus belonging to the genus Agrocybe within the family Strophariaceae. It typically produces small, tan to pale brown cap-shaped fruiting bodies and is often found growing in clusters or scattered on lawns, grassy areas, forest floors, decomposing wood, and soil-rich ecosystems. The species typically inhabits forest floors, decomposing wood, and soil ecosystems, obtaining nutrients by breaking down dead organic matter. Its geographic range includes several European countries — Belgium, Denmark, Norway, Portugal, and Sweden — as well as the United States in North America. <em>Agrocybe pediades</em> is assessed as Least Concern on the IUCN Red List, reflecting its broad distribution and apparent stability. Biological traits of this species, including specific data on fruiting body size, lifespan, and ecological preferences, remain poorly documented in the scientific literature. Like other members of its genus, it typically fruits during warmer months and often appears after rainfall in nutrient-rich grassland and woodland habitats.