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What is Barley?


OSU barley in the news


Craft Malting  

Barley FAQs (To download a poster (pdf format) for each topic - click on the topic header)

What is the difference between a 2-row and 6-row barley?

This is a story of seeds, heads, history, and perceptions. 2-row barley has 2 rows of seed on each spike (head) and 6-row barley has 6 rows of seed on each spike (head). Botanically speaking, a 2-row has 1 fertile floret per rachis node and a 6-row has 3 fertile florets per rachis node. Two genes control the trait: VRS1 and INT-CVRS1 is cloned and the cloning of INT-C will soon be announced. Wild barley is 2-row. The 6-row trait was selected shortly after domestication. The current geographic distributions of 2-row and 6-row varieties (and perceptions regarding their suitability for different end uses) are largely accidents of history.

Is 2-row barley better for malting than 6-row barley?

Better is all in the eye of the maltster/brewer and not the beholder. There is no absolute relationship between row type and quality. For the purposes of making fine beer, there are great (and terrible) 2-rows and there are great (and terrible) 6-rows. With a suitably plump 6-row, there no way to look at a malting quality parameter spec sheet and know if the data are from a 2-row or a 6-row. Likewise, just knowing the spike type of a variety will not tell you if that variety would make great, middling, or awful malt. Is malting with winter 6-row an abomination?

What are the Big Four barley diseases in western Oregon? What do they look like? How can I control them? 

Barley Yellow Dwarf Virus
Transmitted by aphids, Barley Yellow Dwarf Virus (BYDV) infects the plant and blocks phloem tissues, reducing the transport of sugar through the leaves. This results in yellowing (and hence the name). If a plant is attacked early in development, it becomes severely dwarfed and heads may be sterile. Control? Plant as late as you can, in order for fall frosts to kill aphids. You can apply insecticides to seed (pre-planting) or to the emerging crop.  This is a nasty disease and can be a crop killer. Genetic resistance is available, but the viruses (and aphid vectors) are both a challenge to deal with.  This is the biggest of the Big Four and one to keep an eye on.

Stripe Rust (Puccinia striiformis)
Stripe Rust is a fungus that produces bright orange pustules in stripes along the leaf (hence the name). Spores easily rub off and will color clothes (and pets) orange if the infestation is severe. Stripe rust primarily affects leaves but it can spread to leaf sheaths and heads. This disease can be a crop killer. Control? Use resistant varieties – they are available. A susceptible variety can be destroyed by stripe rust, even with multiple applications of foliar fungicide. This disease ranks #2, because you can deal with it.

Loose Smut (Ustilago hordei)
Smut is a fungus that infects open flowers and becomes established inside the embryo of the developing grain.  The smut mass replaces the entire head, except the rachis, of an infected plant. This leaves a mass of dark brown powdery spores held by a thin membrane. Once the membrane breaks, spores float onto neighboring heads and spreading the disease. Smut heads usually emerge before healthy heads. Control? Rogue the crop, remove infected heads from the field and destroy them.  Or apply fungicides to seed. Keep on top of this disease: it will always be an irritation but in need not be a problem (hence the #3 position).

Scald (Rhynchosporium secalis)
Scald is a fungus that causes large blotches with dark brown margins surrounding bleached tissue. The water-soaked lesions give rise to the name of the disease. These lesions can kill an entire leaf and may infect heads and grain. Water splash from rain or irrigation contributes to spread of the disease from lower leaves and on up the plant.  This disease usually looks worse than it is. Control? Use resistant varieties – they are available. Foliar fungicides will keep the disease at bay.  This disease ranks  #4 – it is useful, at least, for distinguishing barley from wheat at vegetative stages – from 50 feet.

There are many, many more diseases of barley! Some of these may occur in Western Oregon.

What is the difference between hulled, hull-less, and pearled barley?

Barley grain comes off the plant in two “styles”: with adhering hulls and without adhering hulls. One gene (NUD) determines whether or not the hulls (lemma and palea) adhere to the grain. If the hulls adhere, the barley is (correctly) termed “hulled”.  Most barley varieties in most of the world are hulled. The hulls can be removed by vigorous mechanical abrasion, in which case the barley is “pearled”. If the hulls do not adhere, the barley is said to be hull-less (or naked). At first glance, hull-less barley looks like wheat. On closer inspection, there are subtle differences in grain shape and size. Hull-less barley varieties were formerly found in far corners of the world (such as the Himalayas and Andes) where barley remained a key part of human diets. With the burgeoning interest in whole grains (and a desire to dispense with pearling), there are more hull-less varieties available. Hull-less barley requires twice the cooking time (and liquid) as pearled barley.

Hulled, pearled, and hull-less barley grain all contain beta-glucan, a source of soluble dietary fiber that is responsible for lowering cholesterol. The Food and Drug Administration (FDA) ruled in 2006 that barley foods may carry a health claim specific to soluble fiber and coronary heart disease. Qualifying products may use the following claim: “Soluble fiber from foods such as [name of food], as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease. A serving of[name of food] supplies [x] grams of the soluble fiber necessary per day to havethis effect.”  Pearled barley has about the same cooking time as rice. Hull-less barley requires twice the cooking time (and liquid) as pearled barley.

Note: the term “hulled” is sometimes (and confusingly) used to describe barley grain that has been “de-hulled”. That is, the grain had an adhering hull which was removed.  Keep it simple – use the term hulled to refer to barley grain with the hull on!

What is the difference between a malting barley variety and a feed variety?

Barley malt is the perfect combination of starch, enzymes, flavors, and aromas for brewing, distilling, baked goods, cereals and confections.  There are many types of barley malt – from light to dark – but all are produced by variations on two principal themes: germination and kilning.  Different end-uses require different malt quality specifications.  There are rigorous certification processes to certify that varieties are suitable for malting. Some of the principal characteristics used to define malting quality are protein (low, moderate, or high), malt extract (high) , enzyme activity (moderate to high), and beta glucan (low).  In general, malt barley commands a premium over feed barley, but yield less.

Feed barley is food for animals.  Extensive research has documented that varieties differ in their feeding properties and that some varieties are excellent feed for ruminant and non-ruminant animals. Be careful with barley and chickens, unless you want to deal with "sticky droppings". Unfortunately, feed barley is generally not accorded the respect it deserves in feed markets: it is simply sold by the ton, with a minimum specification for test weight and perhaps kernel plumpness. Feed barley prices are often so low that farmers will grow any other crop - if they can do so.  As a consequence, barley’s adaptability to extreme climates makes it an important feed grain only in areas where other feed grains, like maize, have difficulty growing. A unique type of feed barley has hoods, rather than awns. Hooded types are usually cut at the soft dough stage for hay or silage. The lack of awns allows makes for lip-smacking eating.

A rule of thumb is that good malt barley is good feed barley, but not the reverse. Of course, if only feed barley was available, enterprising folks would learn to make decent malt from it. Many genes determine malting and feed quality; two genes determine the hooded vs. awned trait.

What is the difference between winter and spring barley, and what the *%^&(+ is a facultative barley?

Growth habit of barley is simple to describe but harder to define. There are three growth habit classes – winter, facultative and spring.  A winter barley is planted in late fall and is harvested the following summer (e.g. 9-10 months from planting to harvest). A spring barley is planted in the spring and harvested the same summer (e.g. 4 – 5 months). If you plant a winter barley in spring, it will not flower, or it will flower so late that the yield will be abysmal. If you plant a spring barley in the fall, it will (in many temperate environments) die from low temperature injury. A facultative barley can be planted in the spring or the fall.   Growth habit is controlled by many genes but there are three principal physiological traits involved: vernalization sensitivity, photoperiod sensitivity, and low temperature tolerance. Vernalization sensitivity means the plant needs exposure to low temperature before it can flower. Winter barleys are vernalization-sensitive whereas facultative and spring types are not. Photoperiod sensitivity means the plant will not flower until the daylength reaches a critical threshold (usually greater than 12 hrs). Many winter barleys, most facultative barleys, and few spring barleys are sensitive to short days. Low temperature tolerance is an induced trait. Winter and facultative barleys are more cold tolerant than spring barleys.  The three traits are correlated (e.g. many cold tolerant barley varieties are vernalization- and photoperiod-sensitive. But, correlation, as they say, is not necessarily causation.  An advantage to planting in the fall (with winter or facultative varieties) is that irrigation is not needed or required to get maximum yield. In the Willamette Valley, Mother Nature does the watering for you.  The end uses of barley (feed, food, and malt) are independent of growth habit. In other words, there are winter, facultative, and spring varieties with the attributes you want.

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