Brook Alder vs Common Crabgrass

Alnus maritima compared with Digitaria ciliaris

Key Differences

• Brook Alder is Endangered while Common Crabgrass is Not Evaluated.

Taxonomic Classification

Rank	Brook Alder	Common Crabgrass
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Magnoliopsida (Dicots)	Liliopsida (Monocots)
Order	Fagales (Beeches & Oaks)	Poales (Grasses)
Family	Betulaceae	Poaceae (Grass Family)
Genus	Alnus	Digitaria
Species	Alnus maritima	Digitaria ciliaris

Evolutionary Relationship

Brook Alder and Common Crabgrass share a common ancestor at the Phylum level: Magnoliophyta. (Flowering Plants)

Conservation Status

Brook Alder

EN — Endangered

Common Crabgrass

NE — Not Evaluated

Physical Characteristics

Attribute	Brook Alder	Common Crabgrass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brook Alder

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Distributed across Belgium, France, Netherlands, and United Kingdom. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Crabgrass

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Africa (8 countries), Asia (8 countries), Europe (18 countries), North America (10 countries), Oceania and the Pacific (12 countries), and South America (5 countries).

Brook Alder

The Brook Alder (Alnus maritima) is a species in the genus Alnus. It is currently classified as Endangered on the IUCN Red List. Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Common Crabgrass

<em>Digitaria ciliaris</em>, commonly known as common crabgrass or southern crabgrass, is an annual grass in the family Poaceae. It has a near-cosmopolitan distribution, occurring across tropical, subtropical, and warm temperate regions on multiple continents. This species typically colonizes disturbed habitats including lawns, gardens, roadsides, cultivated fields, and waste ground, making it one of the most widespread grass weeds in the world. Common crabgrass spreads rapidly via its sprawling, branching stems that root at the nodes when they contact moist soil. It produces slender, finger-like racemes bearing small, paired spikelets. The species thrives in warm weather and full sun, declining with the onset of cooler autumn temperatures. While it is considered a troublesome weed in many agricultural and horticultural contexts, it also provides ground cover and food for various seed-eating birds. Biological traits of this species remain poorly documented in the scientific literature.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇫🇷 France 🇳🇱 Netherlands 🇬🇧 United Kingdom