Melilotus officinalis (L.) Lam.
yellow sweet-clover (yellow sweetclover)
Fabaceae (Pea family)
Introduction to Vascular Plants
yellow sweet-clover (yellow sweetclover)
Fabaceae (Pea family)
Introduction to Vascular Plants
Species Information
General:
Biennial or annual herb from a strong taproot, sweet-scented in drying; stems erect, 0.5-2 m tall, freely branched, glabrous to sparsely short-hairy.
Leaves:
Alternate, pinnately compound; leaflets 3, elliptic-oblong to egg-shaped, short-hairy to glabrous, 1-4 cm long, the margins fine-toothed to near the base; stipules entire or with 1-3 basal teeth, 5-10 mm long, joined at the base to the leaf stalk.
Flowers:
Inflorescence a slender, spike-like, axillary raceme of 20 to 50 or more pea-like flowers, the racemes 3-15 cm long, on stalks from shorter to longer than the leaves; corollas yellow, 5-7 mm long, the banner and wings equal to or longer than the keel; calyces bell-shaped, the tube 1-2 mm long, the teeth narrowly lance- to awl-shaped, as long as the tube.
Fruits:
Pods, egg-shaped, somewhat flattened but still plump, nodding, 3-5 mm long, somewhat leathery, glabrous, cross-ribbed, 1-chambered; seeds 1 or 2.
Illustration
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
USDA Species Characteristics
Flower Colour:
Yellow
Blooming Period:
Summer
Fruit/Seed characteristics:
Colour: Yellow
Present from Summer to Fall
According to the USDA, this species is a known allelopath.
Source: The USDA
Ecology
Ecological Framework for Melilotus officinalis
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
| Site Information |
Value / Class |
||
|
Avg |
Min |
Max |
|
| Elevation
(metres) |
895 | 385 | 1813 |
| Slope
Gradient (%) |
24 | 0 | 80 |
|
Aspect (degrees) |
192 | 50 | 335 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
3 | 0 | 7 |
| Modal
Nutrient Regime
Class |
D | ||
| #
of field plots species was recorded in: |
59 | ||
| Modal
BEC Zone Class |
IDF | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
BG(6), BWBS(2), ESSF(2), ICH(4), IDF(31), MS(4), PP(5), SBPS(1), SBS(2) | ||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Mesic to dry fields, roadsides and waste places; frequent in S half of BC east of the Coast-Cascade Mountains, rare to the W and N; introduced from Eurasia.Status Information
Synonyms
Synonyms and Alternate Names:
Melilotus arvensis Wallr.
Melilotus leucanthus W. D. J. Koch ex DC.
Melilotus lutea Gueldenst.
Melilotus officinalis var. micranthus O. E. Schulz