Bird's-foot Trefoil (Corniculatus)

The Bird's-foot Trefoil (Corniculatus) is generally described as a perennial forb/herb. This is not native to the U.S. (United States) and has its most active growth period in the spring and summer . The Bird's-foot Trefoil (Corniculatus) has green foliage and inconspicuous yellow flowers, with a moderate amount of conspicuous brown fruits or seeds. The greatest bloom is usually observed in the early spring, with fruit and seed production starting in the spring and continuing until summer. Leaves are not retained year to year. The Bird's-foot Trefoil (Corniculatus) has a moderate life span relative to most other plant species and a moderate growth rate. At maturity, the typical Bird's-foot Trefoil (Corniculatus) will reach up to 2.4 feet high, with a maximum height at 20 years of 0 inches.

The Bird's-foot Trefoil (Corniculatus) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by seed. It has a slow ability to spread through seed production and the seedlings have low vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -43°F. has medium tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Erosion control: Birdsfoot trefoil is used along roadsides to control wind and water erosion.

Wildlife: Birdsfoot trefoil is a choice food for Canada goose, deer, and elk. As ground cover, it provides green cover most of the year and blooms profusely. It is used for pheasant cover on shooting preserves and around ponds at duck clubs.

Livestock: This species is used for green chop, hay and pasture. It is seeded in combination with grass and grazed as a non-bloating legume. It yields 4 tons of hay per acre on deep, well-drained soils receiving irrigation or adequate rainfall. As a dryland pasture legume, birdsfoot trefoil produces 20% more growth after July 1 than most dryland grass legume mixtures.

General Characteristics

Birdsfoot trefoil is a moderately long-lived herbaceous perennial legume. It has a well developed, branching, tap-like root with side roots near the soil surface. Most cultivars are erect and grow to a height of 2 to 3 feet. The stems are slender, branch well, and are moderately leafy. Leaves are smooth and consist of 5 leaflets. The bloom is made up of a cluster of bright yellow flowers arranged in a whorl at the end of the flowering stems. When ripe, the brown seed pods extend outward from the stalk and look like a bird's foot. The plant remains green and succulent during and after seed ripening. There are an average of 375,000 seeds per pound.

Required Growing Conditions

Birdsfoot trefoil is generally used in areas that receive 20 inches of precipitation or more. It is suited to low and moderately fertile soils with relatively poor internal drainage but is usually less productive than alfalfa on fertile, deep, well-drained soils. It performs well on soils too shallow or too poorly drained for alfalfa. It is equal to alfalfa in tolerance to saline-alkaline soils and is adapted to soils of medium acidity. The best pH range for

Cultivation and Care

For forage production birdsfoot trefoil is typically seeded at 4 to 8 pounds per acre either alone or with a grass. Seeding rates for erosion control practices may run considerably higher depending on the mix and geographic location. Seed should be inoculated and drilled 1/4 inch deep during early spring or late summer, with orchardgrass, timothy, meadow foxtail, or tall fescue. If planting in late summer or in sandy soils, increase seeding depth to ½ inch. Midsummer seedings are hazardous unless soil moisture is above normal and growing conditions are good. Seedbed preparation and seeding must be done carefully. Seed is small and many stands are lost by poor seedbed preparation, deep seeding, inadequate soil fertility, poor inoculation or failure to use specific inoculant, and excessive competition from weeds. The seedbed needs to be mellow, firm and smooth. Band seeding of birdsfoot trefoil is highly recommended. Fertilize and lime according to soil tests. Phosphorous is particularly critical in low fertility soils and is best utilized if banded 1½ - 2“ directly below the seed. Since birdsfoot trefoil seedlings grow quite slowly, rapidly growing weeds will shade and stunt its growth. Early weed control will greatly improve the chance of a successful planting. Control pests, especially spittlebugs and leafhoppers.

General Upkeep and Control

Regrowth of birdsfoot trefoil differs from that of alfalfa in that it originates at buds formed in leaf axils. Close grazing that takes all stem growth is very detrimental to regrowth and stand life. Delay spring grazing until plants are at least 8 inches high. Allow 24 to 38 days regrowth between grazings and leave a 4 inch stubble after grazing. Additionally, 60 day rest periods every 3 years helps to maintain the stand. Hay harvest should leave 4 to 6 inches of stubble to ensure good regrowth.

Birdsfoot trefoil does not cause bloat in ruminant animals. To protect the life of the stand, it does require careful management. Birdsfoot must be allowed to grow to maturity every third year or so in order to produce a seed crop--thus sustaining the stand. Birdsfoot trefoil benefits from readily available phosphorous. Phosphorous should be applied annually based on local soil testing recommendations.

Pests and Potential Problems Crown and root rots are the most significant diseases of birdsfoot trefoil. The trefoil seed chalcid, Bruchophagus kolobovae Fed., is a small, black, wasp-like insect that can be destructive in seed fields.

Cultivars, Improved, and Selected Materials (and area of origin) Some of the most common upright or hay-type varieties used in the Northeast US are ‘Norcen’, ‘Viking’, ‘Mansfield’, and ‘Leo’. ‘Empire’, ‘Dawn’, and ‘Fergus’ are low-growing, pasture-type varieties. The European trefoil is not a variety, but merely refers to trefoil seed imported from Europe. European trefoil is lower yielding than the US varieties and this seed is not recommended. ‘Cascade’ (France), ‘Granger’, ‘Mackinaw’ (IA naturalized), and ‘Kalo’ (France) are principal cultivars in the west. Seed is readily available at commercial seedhouses.

Control Please contact your local agricultural extension specialist or county weed specialist to learn what works best in your area and how to use it safely. Always read label and safety instructions for each control method. Trade names and control measures appear in this document only to provide specific information. USDA, NRCS does not guarantee or warranty the products and control methods named, and other products may be equally effective.

Plant Basics
Growth Rate Moderate
General Type Forb/herb
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Moderate
Plant Nativity Introduced to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Early Spring
Displays Fall Colors No
Shape/Growth Form Single Crown
Drought Tolerance Medium
Shade Tolerance Intolerant
Height When Mature 2.4
Vegetative Spread None
Flower Color Yellow
Flower Conspicuousness Yes
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Spring Summer
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Seed
Moisture Requirements Medium
Cold Stratification Required No
Minimum Temperature -43
Soil Depth for Roots 14
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Rapid
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 5–8 pH
Precipitation Range 16–16 inches/yr
Planting Density 0–0 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 14
Minimum Frost-Free Days 90 day(s)
Salinity Tolerance Medium
CaCO3 Tolerance Medium
Sustainability & Use
Leaf Retention No
Palatability High
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database,
National Plant Data Center, Baton Rouge, LA 70874-4490 USA