Secale cereale L.

Image of a rye field.

Is a tufted annual or biennial grass reaching up to 5 feet. It is the tallest and most winter hardy annual cereal crop. Rye is mainly used for its grain, but is also a valuable fodder (for pasture, hay, or silage) and cover crop during winter. Cereal rye is the most commonly used small grain for spring forage. Tolerant to drought, low pH, and low fertility. 

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

Species Selection Characteristics

Annual Precipitation (inches): 
16 to 20
20 to 24
24 to 28
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
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: 
moderately well drained
well drained
Flooding Tolerance: 
3-6 days
Soil Salinity Tolerance: 
Moderately tolerant, 3–6 dS/m

Identification Characteristics

Growth Season: 
Identification Characteristics: 

Tall, tufted grass reaching up to 5 feet (1.5 m) in height.

Growth Habit and Stand Life

Growth habit: Erect bunchgrass

Life Cycle: 
Winter annual

Climate and Soil Suitability Zones

Climate Tolerances: 

Temperature: Tolerates conditions as low as -30°F once it is well-established. Optimum growth temperature is 64.4°F, but vegetative growth can occur at temperatures as low as 38°F. 

Precipitation: 18 inches or greater of annual precipitation required

Soil Tolerances: 

pH: Tolerant of strongly acidic to moderately alkaline soils (5.1-8.4)

Drainage class: WD-MWD

Salinity: Moderately tolerant, 3-6 dS/m

Quantitative Tolerances: 




Suitability Maps

Suitability patterns for forage species are caused by different factors in different locations. Low winter temperatures limit the northern range of many species, while low precipitation limits the western range of species in the semi-arid west. Low summer temperatures limit the range of species with increasing elevation while high summer temperatures limit the range in the desert southwest and hot and humid southeast. Soil characteristics (pH, drainage, and salinity) also limit the suitability zones of forage species. However, soil amendments (liming and drainage tiles) can alleviate many of these limitations. Thus, NRCS Soil Survey data should be informed and revised by management mitigations.

Nine maps have been developed; 1) 30-year long-term July maximum temperature 2), 3) 30-year long-term annual precipitation, 4) soil pH, 5) soil drainage, 6) soil salinity, 7) combined climate factors, 8) combined soil factors, and 9) combined climate and soil factors.

Yield Potential and Production Profile

When harvested during the boot stage, a yield of 2 to 3 tons of dry matter per acre (4.48-6.72 MT/ha) may be achieved.


There are relatively few varieties of cereal rye available. Spring-sown varieties are available as an alternative to common rye as a winter crop. Drought tolerance among varieties varies, with diploid varieties more tolerant than those that are tetraploid. Currently most cereal rye seed planted as forage or cover crop is: “variety not stated” (VNS). However, there are cultivar evaluation trials conducted at numerous land grand universities.

Management Level Required

Suitable Management Level: 

Quality and Antiquality Factors

Quality Factors: 

Rye harvested at boot stage typically produces 2 to 3 tons of dry matter per acre (4.48-6.72 MT/ha) with quality levels acceptable for many animal production groups. Thee nutritional content of cereal rye forage is widely variable depending upon the maturity of the forage; vegetative stage rye can have a crude protein content exceeding 20% and a TDN of 70%, whereas boot to full-heading can vary from 13 to 7% CP and 63 to 53% TDN, while straw may be only 4% CP and 44% TDN.

Anti-quality Factors: 

Ergot (Claviceps purpurea) disease and ergot poisoning are the main hazards associated with rye. Ergotism is the effect of long-term ergot poisoning, traditionally due to the ingestion of the alkaloids produced by the fungus that infects rye and other cereals. Dark-purple or black grain kernels, known as ergot bodies, can be identifiable in the heads of cereals just before grain harvest. Grazing vegetative rye or harvesting for silage or hay in the boot stage prevents the development of the ergot bodies. Milk from livestock grazed on rye may have an off flavor.

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