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Last updated on February 23, 2014

Note: This information was developed from lecture notes for the Farm and Industry Short Course at the University of Wisconsin.


Oats are not a major world crop

Oats are a cool season cereal, so most of the world's acreages are in cool, moist, temperate climates


  • Russia - 45% of world's acreage
  • USA and CANADA
  • EUROPE - Oats are very well adapted to N. European conditions


  • Largest acreages of oats in the 1920's, with 40-45 million acres harvested annually
  • Acreages dropped slightly until the mid-1950's, & have dropped substantially since then for several reasons:
  • Switch from horse power to mechanical power in the 1930's
  • Northward movement of corn and soybeans in the Midwest in the 60's, 70's, & 80's
  • Oats traditionally considered a low-value cash crop. 70% of the oats are fed on the farm where they were produced, so there has not been substantial marketing activity
  • Use of alternate sources of bedding such as cornstalks, shredded paper, etc
  • Direct seeding of alfalfa
  • What's ahead for oats? 
  • LEADING STATES: South Dakota, Minnesota, Wisconsin, Iowa, North Dakota, and Texas usually has 1 1/2 million acres of planted oats, but most of their oats are grazed out


Oats have retained some importance in US agriculture for several reasons:

Their feeding value for certain classes of livestock HORSES, DAIRY, CATTLE, POULTRY,and YOUNG PIGS

  • Breeding stock of most classes of livestock
  • Oats are not used very much in fattening rations due to relatively low energy value
  • Cattle above 400 lbs
  • Pigs above 40 lbs

Advantages as a feed:

  • Oats are high in FIBER
  • Oats are high in PROTEIN %
  • Oats have excellent protein QUALITY
  • Oats are high in oil
  • Among the cereals, oats are the richest sources of three minerals Ca, P, Fe and three vitamins Thiamine, Riboflavin, Vit E
  • Summary: Oats: a good conditioning feed where high energy is not needed

The use of oats as HUMAN FOOD is increasing

  • Recent research has shown that oat fiber in the human diet significantly lowers blood-serum cholesterol levels.
  • FIBER in the oat kernel is concentrated in the BRAN (pericarp)
  • To reduce cholesterol, fiber in the diet must be WATER-SOLUBLE. Oat bran is water-soluble.
  • Barley is also capable of reducing cholesterol levels because its bran is water-soluble
  • The bran of wheat, rye, triticale, and corn is NOT water-soluble, so these grains are not capable of reducing cholesterol levels in humans and livestock

Usefulness in crop rotations

  • Oats do very well after corn & soybeans
  • Oats break up disease cycles
  • Oats are used to establish alfalfa underseedings

Ease of growing and handling

  • Relatively easy to grow and manage
  • Relatively low input crop Don't require a lot of applied fertilizer
  • Normally don't have drying costs

High yields of excellent quality straw

Use of oats as a forage is increasing


The two principal types of cultivated oats are Avena sativa and Avena byzantina

Avena sativa

  • Common oat or cultivated oat
  • Adapted to cool, moist regions such as the northern US, Canada, northern Europe, & Chile

Avena byzantina

  • Cultivated red oat or common red oat
  • More tolerant of heat & humidity, so adapted to warmer climates.
  • Grown in southern US, Mediterranean region, Australia, Brazil, etc
  • A. byzantina varieties are normally planted in late fall or early winter and are harvested in late spring or early summer

May be true winter types or facultative types

  • Facultative - are spring types that can function as a winter type and don't require vernalization
  • In central & southern TEXAS, oats are planted in late November and early December and usually are harvested in late April through mid-May

Water requirement

  • Oat plants require more water per lb of DM produced than other small grains, but they do better in cool, cloudy conditions than other small grains

Warm, humid weather

  • Oats are especially sensitive to warm weather between heading and ripening
  • Warm temperatures often result in more diseases, blasting, and light seeds
  • Red oats tend to be more heat tolerant than common oats

Adaptability to soil conditions

  • Oats can be grown successfully on a wide range of soil types
  • Main requirements are that the soil be WELL DRAINED and REASONABLY FERTILE
  • Oats have good tolerance to acid soils
  • Rye - most tolerant to soil acidity Oats Triticale Wheat Barley - least tolerant


  • Most oat varieties are long day plants. Need at least 12 hours of daylight to induce flowering
  • Photoperiod response is affected by temp
  • Cooler temp's delay flowering

Winter hardiness

  • There are both winter and spring types of wheat, oats, barley, rye, & triticale
  • Rye - most winterhardy Wheat Triticale Barley Oats - least winterhardy - grown in SE US


Oats are an annual grass



  • Fibrous root system
  • May penetrate 3-4 ft into soil, but most are concentrated in upper 1 ft


  • Most oat culms (straws) have 7 leaves
  • Oat leaf consists of blade, sheath, & ligule
  • Alternate arrangement
  • 4th leaf is largest
  • No auricle


  • BARLEY - Large auricle
  • WHEAT - Small auricle
  • RYE - V. small auricle
  • OATS - No auricle


The oat infloresence is a panicle


  • Rachis - central axis of the panicle
  • Panicle branches - 5-7 whorls
  • Pedicels - Connect panicle branches and spikelets


  • A. sativa & A. byzantina have 2-3 florets/spikelet
  • Florets are connected by the RACHILLA
  • Spikelets are surrounded by glumes


  • Lemma & palea
  • 3 stamens - Filament & anther
  • Pistil - stigma, style, & ovary


  • Oats are highly self-pollinating (99% +)
  • Pollination begins in top spikelet as panicle is emerging from the boot
  • Takes 5-7 days for entire panicle to pollinate
  • Pollen germinates immediately and fertilization occurs within 4-6 hrs
  • Pollination usually occurs between 1 & 4 p.m.


3 primary components of yield:

  • Heads/plant=tillering
  • Seeds/head
  • Ave wt/seed

Tillering - usually determined during first 3 weeks after emergence

Seeds/head - usually determined between 3 and 6 weeks after emergence determined after tillering and before stem elongation 

Ave wt/seed determined after heading

Don't want excessively warm temp's during any of these phases

For high yields and good grain quality, want good moisture, good fertility, and relatively cool conditions throughout the season


  • N (fertility)
  • Planting date
  • Temp & Moisture
  • Population
  • Variety


At maturity, A. sativa and A. byzantina grain consists of 60-75% GROATS: kernel; outer layer is the pericarp 40-25% HULLS: lemma & palea - Low in nutritional value

Varieties with 70-75% groat are desirable

Groat composition:

  • 65-70% ENDOSPERM - protein and carbohydrate
  • 25% BRAN (Pericarp) - fiber
  • 7% EMBRYO - oil and protein

Oats are considered to be high in both QUANTITY and QUALITY of protein


  • whole oats often have 12-15% prot
  • Oat groats often have 16-18% prot
  • Genetics are important
  • Dal oats - high in protein
  • Ogle oats - low in protein

QUALITY of oat protein

  • Oats have an excellent balance of amino acids
  • Oats are high in LYSINE

Grain Standards

TEST WT (Bushel wt)

  • Test wt is an important part of grain quality, especially when considering transportation and storage costs.
  • Want to transport and store as much wt/unit volume as possible
  • Test wt may not be strongly associated with feeding value. If test wt is low, animal simply eats more grain


  • US #1 36 lbs/bu
  • US #2 33 lbs/bu
  • US #3 30 lbs/bu
  • US #4 27 lbs/bu
  • SAMPLE < 27 lbs/bu
  • There are 2 special grades of oats that deal with TEST WT:
    • HEAVY OATS - Oats that have a test wt of 38 lbs or more but less than 40 lbs/bu
    • EXTRA HEAVY OATS - Oats which have a test wt of 40 lbs or more

There are other aspects of grain quality that are important, but in summary oat growers and processors prefer PLUMP, BRIGHT kernels that have HIGH TEST WT, HIGH GROAT %, and are medium to high in PROTEIN and OIL p 5-32, GCM 13


AVENA FATUA = Wild oat

The most widely distributed of the wild oat species

A persistent, troublesome weed in the Western US and Western Canada - Worst weed problem in barley, wheat, and oat fields in these areas

Annual US and Canadian losses caused by A. fatua are in the millions of dollars

Plants are more VIGOROUS and COMPETITIVE than barley, wheat, and oats, especially in fertile, productive areas in fields

Avena fatua is difficult to eradicate because of SHATTERING and DORMANCY

Avena fatua is controlled quite well in areas that are predominantly row-cropped and/or grown to perennial forages such as alfalfa 14

AVENA STERILIS = Wild red oat

Similar to A. fatua in many characteristics, but not as widely distributed

Common in Middle East countries - Lebanon, Syria, Israel, etc.

Rust resistance genes from A. sterilis have been used to improve resistance in cultivated oats

AVENA NUDA = hull-less oat or naked oat

Hull threshes free when combined, so they're referred to as free-threshing oats

This is not the case with most oat species, where the hull remains intact when the oats are combined

Not common in the US, but fairly common in several areas of eastern Canada

Distinguishing characteristics

  • 5-6 florets/spikelet
  • Long rachilla
  • High test wt


  • On a groat basis, hull-less oats may be lower yielding than A. sativa varieties
  • In Wisconsin, hull-less oats have been V. SUSC. to leaf rust and stem rust
  • Some varieties have shattering problems
  • Storage problems - Rancidity - Groat hairs collect dust - Air flow in bins may be restricted - Difficult to handle in elevators because they don't flow very well

ADVANTAGES of hull-less oats

  • Good feed for gestating sows and feeder pigs
  • Higher energy value than hulled oats
  • Superior ADG & feed efficiency for feeder pigs
  • Poultry: Very good for broilers, but not as good as hulled oats for laying hens


SEEDING DATE: As early as the soil can be worked, but don't work the soil when wet

SEEDING RATE: 1 1/2 to 3 bu/a, depending upon:

Underseeding of alfalfa

  • Seeding rates of 1 1/2 to 2 bu/a are common when alfalfa is seeded with oats.
  • Higher rates may increase yields, but
  • more competition for alfalfa
  • lodging may increase


  • Grain and straw yields may be reduced
  • Grain and straw quality may be reduced
  • Harvest efficiency is reduced
  • Alfalfa may be choked out

Soil fertility: More tillering at higher fertility levels, so seeding rate can be reduced

Soil type: Lighter soils usually have less tillering

SEEDING DEPTH: 1 to 2", but not deeper

TILLAGE: Objective is to incorporate residue sufficiently to do a good job of planting with a GRAIN DRILL

NEWER DRILLS: More uniform planting depth, better soil-seed contact, and are heavier. Good soil-seed contact is crucial for high yields Will have deeper rooting earlier in the season

Spring grains after corn and alfalfa in Wisconsin: Ground is usually fall-plowed

Spring grains after soybeans

  • Fall tillage shouldn't be necessary
  • Field cultivate, then drill immediately
  • No-till after solid-seeded soybeans


  • ICM techniques not widely used on oats in the US
  • Not a high value cash crop unless both grain & straw are considered
  • Straw has often been more valuable than grain


  • Oats do not require large applications of fertilizer, but in many cases some fertilizer is helpful after corn
  • After soybeans - Be careful! Although many feel that a soybean crop will add N to the soil, research indicates that this may not be true unless the entire soybean plant is plowed under
  • However, soybeans loosen the soil more extensively than other crops. Oats following soybeans usually have rapid, early root penetration in the soil, which will ultimately improve grain and straw yields
  • How much fertilizer should be added? The key nutrient for small grains is NITROGEN because it has a substantial effect on plant performance
  • N applications should be based on soil test results
  • As fertility level increases, variety selection becomes increasingly important
  • N applications:
    • Oats, barley, and rye - relatively low
    • Wheat and triticale - higher amounts
  • When should fertilizer be applied? Most fertilizer applications to oats and other spring grains are incorporated prior to planting


  • If a good stand is established, the need for chemical weed control is minimized, especially in winter grains
  • If alfalfa is being established with spring small grains, 2,4-D is often used for broadleaf weed control
  • However, research has shown that medium to high rates of 2,4-D may cause lodging of oats - SDSU research - 1/2 lb 2,4-D/a can cause considerable lodging in some oat varieties - 1/4 lb/a is safer - Less lodging with MCPA than 2,4-D - 3 to 4 leaf stage is best time to apply 2,4-D Later application may reduce yields
  • Banvel could be used if alfalfa is not being established and soybeans in the area haven't emerged
  • Spot-spray with Roundup during off-season
  • Be aware of herbicide residue problems following corn and soybeans


  • Need to be timely for high yields of GOOD QUALITY grain & straw
  • Growers who wait too long to harvest usually have problems with
  • QUALITY of Grain & Straw
  • STRAW an important component of small grains
    • Winter grains > spring grains Tall varieties > short varieties Oats = Spring Wheat > Barley 2-rowed barley > 6-rowed barley


1987 Wisconsin oat acreage 830,000 acres - grain and straw (65%) 470,000 acres - forage and setaside (35%)

1988 Wisconsin oat acreage 580,000 acres - grain and straw (48%) 620,000 acres - forage and setaside (52%)

For many years, small grains were harvested in late milk to early dough stage, but since early 1980's, small grains have been harvested in late boot to early heading stage

Early harvest results in

  • Higher CP%
  • Improved digestibility (lower ADF)
  • Greater intake (lower NDF)
  • Lower forage yields
  • Early removal of competition from alfalfa
  • More regrowth from small grain stubble

Time of harvest often dictated by intended use of forage

  • Earlier forage harvest for milking cows
  • Later harvest for dry cows and beef cattle

Late oat varieties usually are higher in forage yield but lower in forage quality than short, early oat varieties

Currently, some dairy farmers are planting oat-pea and barley-pea mixtures and harvesting them at early small grain heading. Most are using Trapper peas. Common rates of mixtures are 1 to 1 1/2 bu of small grains/acre (10-15 seeds/ft2) 1 to 1 1/2 bu of peas/acre (5-8 seeds/ft2)

Effect of adding peas

  • Forage yield increases have been inconsistent
  • Forage quality increases have been consistent
  • Quality improves in proportion to pea seeding rate

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