Trifolium hybridum L.

Alsike Clover field flowering - UTAS - Hall Hurst

Herbaceous, short-lived perennial forage legume with fine-stemmed, semi-erect, indeterminate growth habit. It has no stolons or rhizomes. Used for pasture or hay in mixtures with other legumes and cool-season grasses in humid regions with mild winters. Behaves as an annual or biennial at higher elevation and colder winter climate zones. Can also be used for soil improvement in wet, acid soil conditions.

Soil Improvement (Green manure)
Soil Protection (Cover Crop)

Species Selection Characteristics

Annual Precipitation (inches): 
28 to 32
32 to 36
36 to 40
40 to 50
50 to 60
60 to 70
70 to 80
80 to 100
100 to 120
120 to 140
140 to 160
> 160
Plant Hardiness Zones (cold tolerance): 
Heat Zone (July Mean Max Temperature): 
< 14 °F
14 to 18 °F
18 to 22 °F
22 to 26 °F
26 to 30 °F
30 to 34 °F
34 to 38 °F
38 to 42 °F
42 to 46 °F
46 to 50 °F
50 to 53 °F
53 to 56 °F
56 to 59 °F
59 to 62 °F
62 to 65 °F
65 to 68 °F
68 to 71 °F
71 to 74 °F
74 to 77 °F
77 to 80 °F
80 to 84 °F
84 to 88 °F
88 to 92 °F
Soil pH Tolerance: 
Strongly acid, 5.1–7.3
Moderately acid, 5.6–7.3
Moderately acid to moderately alkaline, 5.6–8.4
Slightly acid to moderately alkaline, 6.1–8.4
Near neutral, 6.1–7.3
Soil Drainage Tolerance: 
poorly drained
somewhat poorly drained
moderately well drained
well drained
somewhat excessively drained
Flooding Tolerance: 
7-30 days
Soil Salinity Tolerance: 
Moderately sensitive, 1.5–3 dS/m

Identification Characteristics

Growth Season: 
Identification Characteristics: 

Inflorescence is an almost spherical axillary raceme about 0.75-1.4 inches (2-3.5 cm) in diameter.  Seed head is similar to white clover, but more pinkish-white. Each raceme has 30-50 white or pale pink flowers that are 0.23-0.43 inches (6-11 mm) long. Flowers bend downwards after pollination and are brown at maturity.

Palmately trifoliolate leaves with equal-length petiolules. Can be distinguished from red clover by the absence of pubescence (hairs), lack of crescent-shaped marks on each leaflet, more conspicuously toothed leaflets, and prominent veins that appear to extend beyond the edge (margin). Stipules are continuously tapering, with greenish veins, and sharply pointed.

Stems are indeterminant, semi-erect, glabrous (not hairy), long, thin, and hollow, usually reaching 1-3 feet (30-90 cm).

Has a many-branched taproot that penetrates deep into the subsoil.  

Seeds are small (1 mm long, 0.9-1.0 mm wide) with 700,000 seeds/lb (1,540,000 seeds/kg). They are heart-shaped, greenish-brown, with tinges of red, aging to a darker brown (less red than white clover seed). Each seed pod is about 1 cm (0.4 inches) long and contains 3-5 seeds that vary in color from dull green to nearly black.

Growth Habit and Stand Life

Alsike clover has a fine-stemmed, semi-erect, indeterminate growth habit. It has no stolons or rhizomes. It is a short-lived perennial.

Life Cycle: 
Short-lived perennial

Climate and Soil Suitability Zones

Climate Tolerances: 

Grown in the Pacific Northwest and the Great Lakes region of the upper Midwest. Important forage legume in areas suited to clover-timothy production. Requires 25-40 inches (635-1000 mm) of precipitation or irrigation. Low heat and drought tolerance; requires irrigation if soil moisture is low. Moderate winter hardiness and tolerates frost heaving. 

Soil Tolerances: 

Wet, high clay content soils. Produces well in areas not suitable for red clover. Tolerates long spring flooding of 7-30 days. Tolerates strongly acid soil conditions (pH 5.1-7.3). Moderately sensitive to salinity (1.5-3 dS/m).

Quantitative Tolerances: 

Alsike Clover Suitability Tolerance Values

Suitability Class

Ave Ann Extreme Min (°C/°F)*

July Max


Annual Precip (mm/in)**

Soil pH***

Soil Drainage 

Soil Salinity (dS/m)#








Moderately suited







Marginally suited







*Low temperature: USDA Plant Hardiness Zones – based on average annual extreme minimum temperature: 3b-8b; annual in poorly drained soils in zones 6-7. Latitude suitability: 40-48’ N.

**Not drought or heat tolerant.  Heat Zone – based on Mean Max July Temp: <= 31°C/88 °F.

Rooting: branched taproot to 4 feet (130 cm).

*** Soil pH: NRCS Range and Pasture Handbook, Chapter 3, Table 3-7; Classification for alsike clover classification is Tolerant of Strongly Acid Soils: 5.1-7.3. 

Classifications – tolerant of soils that are: (1) Very strongly acid to strongly alkaline, 4.5–9.0; (2) Very strongly acid, 4.5–7.3; (3) Strongly acid, 5.1–7.3; (4) Moderately acid, 5.6–7.3; (5) Moderately acid to moderately alkaline, 5.6–8.4; (6) Slightly acid to moderately alkaline, 6.1–8.4; (7) Near neutral, 6.1–7.3; (8) Alkaline, 6.7–9.0.

Soil drainage: NRCS Range and Pasture Handbook, Chapter 3, Table 3-4; Classification for alsike clover is Tolerant of PD to WD Soils.

Soil drainage class abbreviations: (1) VPD, very poorly drained; (2) PD, poorly drained; (3) SPD, somewhat poorly drained; (4) MWD, moderately well drained; (5) WD, well drained; (6) SED, somewhat excessively drained; (7) ED, excessively drained.

Percent Relative Yield for Arrowleaf Clover for the classes 1-7: 25, 50, 75, 100, 100, 55, 30.

Flooding tolerance: (1) Very long (>30 days); (2) Long (7-30 days); (3) Brief (3-6 days)

# Soil salinity: NRCS Range and Pasture Handbook, Chapter 3, Table 3- classification for alsike (and Berseem, white, red, strawberry) clover is Moderately Sensitive (1.5-3 DS/m).

Classifications are: (1) Tolerant, 6–10 dS/m; (2) Moderately Tolerant, 3–6 dS/m; (3) Moderately Sensitive, 1.5–3 dS/m.

Suitability Maps

Historically, maps have been drawn based on primary use areas, showing broad geographic areas, e.g. Compendium of Common Forages maps within Forages: An Introduction to Grassland Agriculture, 7th ed. (2018), John Wiley & Sons, Inc.

(Alsike clover generalized adaptation and common use map.)

More highly detailed maps, based on quantitative climatic and soil factor tolerances and using GIS spatial grids, provide information on where species are suitable for a variety of intended uses.

The following collection of maps were developed by a group of Oregon State University scientists, using the PRISM-generated collection of climate factor grids and the NRCS soil characteristics database. The procedure used to produce these suitability maps is described below.

Suitability curves were developed for each clover species for three climate variables (average annual precipitation, average July maximum temperature, and average annual extreme low temperature) and three soil variables (drainage class, pH, and salinity). For each variable and each species, the curves were fit using estimated yield data across the full range of values for the given variable.  

The coefficients for the model equations were applied to spatial data layers representing each climate and soil variable, resulting in spatial outputs of percent yield for each of the clover species and each climate and soil variable. The percent yield layers were then classified into four suitability classes, as follows: 

100%-75% - Suitable
75%-50%  - Moderately suitable
50%-25%  - Marginally suitable
25-0%    - Not suitable

Finally, three "hybrid" suitability layers were produced for each clover species based on combinations of 1) the three climate variables, 2) the three soil variables, and 3) all six climate and soil variables together.  These combined suitability layers were created by selecting for each location the lowest suitability value of the included variables, with the idea that the overall suitability for a species will be limited by the most restrictive factor. 

Data sources
Climate data: 800m PRISM 30-year normals for years 1981-2010 (PRISM Climate Group, Oregon State University,, accessed 2018-01-17)

Soils data:  NRCS STATSGO (Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. U.S. General Soil Map (STATSGO2). Available online at Accessed 2018-01-10)


Quantitative Tolerances GIS-based Maps

The contiguous USA

Minimum Temperature


Climate and Soil

Maximum Temperature


All Soil



All Climate

Click on the thumbnail image to view a larger map.

State Maps
Climate Factors Soil Factors Combined Factors

Minimum temperature


Climate and Soil

Maximum temperature


All Climate



All Soil

Climate Factors Soil Factors Combined Factors

Minimum Temperature


Climate and Soil

Maximum Temperature


All Climate



All Soil

Climate Factors Soil Factors Combined Factors

Minimum Temperature


Climate and Soil

Maximum Temperature


All Climate



All Soil

Yield Potential and Production Profile

Alsike clover grows best in cool, humid climates, with spring growth beginning when temperatures are above 40 °F (5 °C); growth is severely reduced above 86 °F (30 °C).  It has a medium yield potential, comparable to white clover and less than red clover. Mixed with grasses, yearly production on well-managed sites with adequate moisture will be 10,000-12,000 lbs dry matter per acre (~11,000-13,500 kg/ha).

As a cool-season (C3) species, alsike clover's seasonal production profile will show greatest production in late spring and autumn periods.


Once thought to be a hybrid of white and red clover (hence the Latin species name of Trifolium hybridum), alsike is a distinct species. Cultivars are either diploid or tetraploid. Common alsike clover is diploid. Tetraploids are taller, have larger leaves and flowers and are later maturing. ‘Tetra’ is a tetraploid cultivar developed in Sweden.

Management Level Required

Suitable Management Level: 

Quality and Antiquality Factors

Quality Factors: 

Very palatable to cattle. Crude protein and digestibility decline with advancing maturity.

Anti-quality Factors: 

Can cause bloat and photosensitization. Implicated in “alsike clover poisoning” in horses which leads to liver disease. Although the literature does not provide conclusive evidence of causality, do not include in seed mixes for horse pastures.

Image Gallery



Books and Book Chapters

  • Forages: An Introduction to Grassland Agriculture (7th Edition, 2018)
    • Sheaffer, Craig C., M. Scott Wells, and Jerry Nelson. 2018. Legumes for Northern Areas. Chapter 8 In: Forages: An Introduction to Grassland Agriculture. Seventh Edition. John Wiley & Sons, Inc.
  • Clover Science &Technology (Agronomy Monograph No. 25, 1985)

Extension Fact Sheets and Circulars

  • Oregon State University 
  • University of Minnesota: Forage Legumes - Clovers, Birdsfoot Trefoil, Cicer Milkvetch, Crownvetch and Alfalfa. Station Bulletin 608-2003. (Out of print)
  • Purdue Forages - Alsike Clover
  • University of Wyoming - Alsike Clover

USDA NRCS Plant Guide, Fact Sheet, and Plant Profile