Lotus corniculatus (bird's-foot trefoil)

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Lotus, Genus, corniculatus, Species,

Genus & species

bird's-foot trefoil

Fabaceae

Europe, western Asia, northern Africa

Attracts Pollinators Attracts Butterflies Drought Tolerant

SunFull Sun – Part Shade

WaterLow · drought-tolerant

HardinessZones 3–9

Overview

Lotus corniculatus is a prostrate to ascending, taprooted perennial legume in the pea family (Fabaceae) reaching 6–18 inches (15–45 cm) tall with a 12–36 inch (30–90 cm) spread. Stems are solid (not hollow — a key distinction from L. uliginosus), prostrate to ascending, branching from the base, glabrous to sparsely hairy. Leaves appear trifoliate but actually bear 5 leaflets: 3 terminal leaflets in a clover-like arrangement plus 2 stipule-like leaflets at the base of the very short petiole. Leaflets are obovate, 0.2–0.6 inch (5–15 mm) long. Flowers are bright yellow, 0.4–0.6 inch (10–15 mm) long, papilionaceous (pea-shaped), borne in umbel-like clusters of 2–7 on long peduncles. Flowers often develop reddish-orange streaks as they age or under sun exposure. The fruit is a cluster of straight, narrow pods 0.8–1.2 inches (20–30 mm) long, radiating from the peduncle tip like a bird's foot — the source of the common name. A single plant produces 500–5,000 seeds. Seeds have a hard coat and remain viable in soil for 60+ years. Contains cyanogenic glycosides (lotaustralin, linamarin) that release hydrogen cyanide when foliage is damaged; toxic to livestock in quantity, though generally low-risk at normal consumption levels. Nitrogen-fixing via Rhizobium symbiosis. Intentionally planted for erosion control and forage but persists and spreads in roadsides, meadows, and disturbed ground.

Native Range

Native to Europe, western Asia, and northern Africa, occurring in meadows, grasslands, roadsides, and coastal areas from sea level to approximately 8,000 feet (2,400 m). Intentionally introduced to North America for forage and erosion control. Widely naturalized across the Pacific Northwest and all temperate regions of North America.

Suggested Uses

Used in Fabaceae identification courses for teaching papilionaceous flower morphology, the 5-leaflet arrangement, and nitrogen fixation. The bird's-foot pod cluster is a diagnostic teaching feature. Studied in forage legume agronomy, seed bank longevity, and cyanogenic glycoside toxicology. Planted for erosion control on road cuts, mine reclamation sites, and degraded slopes due to drought tolerance and nitrogen fixation.

How to Identify

Distinguished from Lotus uliginosus (big bird's-foot trefoil) by the solid stems (versus hollow), the glabrous to sparsely hairy calyx teeth (versus spreading-hairy), and the prostrate to low-ascending habit (versus more upright). Distinguished from Trifolium (clovers) by the 5-leaflet arrangement (3 + 2 stipule-like), the yellow papilionaceous flowers, and the elongated pods. The bird's-foot pod cluster at the tip of long peduncles is diagnostic.

Appearance

Size & Dimensions

Height6" - 1'6"

Width/Spread1' - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~12 weeks

Flowers: May–September

Spring Summer Fall

Flowers from May through September. Individual flowers last 2–3 days. Clusters of 2–7 flowers on long peduncles bloom sequentially over 10–14 weeks. In the Pacific Northwest, peak bloom occurs in June through August. Pollinated by bees, particularly bumblebees. Flowers redden with age. Pods mature 3–4 weeks after pollination.

Detailed Descriptions

Flower Description

Yellow, often streaked or tinged with red

Foliage Description

Medium green, pinnately compound with 5 leaflets (3 terminal + 2 stipule-like at the petiole base), glabrous to sparsely hairy

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 6-10 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.5 (Acidic to alkaline)

3579

Soil Types

loam sand silt clay

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Management is typically warranted only where the species invades native plant communities or is unwanted in garden settings. Hand-pulling is difficult due to the deep taproot; cutting at ground level prevents seed set but plants resprout. The extremely long-lived seed bank (60+ years) means eradication from established sites is impractical. Competitive planting with vigorous native species reduces establishment in restoration settings. In forage systems, bird's-foot trefoil is managed as a desirable component. The cyanogenic glycosides are a concern for livestock only when large quantities of damaged (wilted or frost-killed) foliage are consumed rapidly.

Pruning

No pruning applicable. Plants are mowed or cut before seed set to prevent seed bank accumulation. In forage settings, cutting at 3–4 inch (8–10 cm) stubble height maintains productivity. The perennial root crown resprouts after cutting.