Straw is an agricultural by-product, the dry stalk of a cereal plant, after the grain or seed has been removed. Straw makes up about half of the yield of cereal crops such as barley, oats, rice, rye and wheat. In times gone by, it was regarded as a useful by-product of the harvest, but with the advent of the combine harvester, straw has become more burdensome to agriculture.
However, straw can be put to many uses, old and new.
The straw-filled mattress, also known as palliasse, is still used in many parts of the world.
It is commonly used as bedding for ruminants and horses. It may be used as bedding and food for small animals, but this often leads to injuries to mouth, nose and eyes as straw is quite sharp.
Straw may be fed as part of the roughage component of the diet to cattle that are on a near maintenance level of energy requirement. It has a low digestible energy and nutrient content. The heat generated when microorganisms in a herbivore's gut digest straw can be useful in maintaining body temperature in cold climates. Due to the risk of impaction and its poor nutrient profile, it should always be restricted to part of the diet.
Hats
There are several styles of straw hats that are made of woven straw.
Until about 100 years ago, thousands of women and children in England were employed in plaiting straw for making hats. These days the straw plait is imported.
Heavy gauge straw rope is coiled and sewn tightly together. This is no longer done entirely by hand, but is partially mechanised.
Horse collars
Working horses are making a comeback, and there is a need for horse collars stuffed with good quality rye straw. Being a "long straw filler" is a highly skilled job.
Construction material: bricks / cob
In many parts of the world, straw is used to bind clay and concrete. This mixture of clay and straw, known as cob, can be used as a building material. There are many recipes for making cob.
When baled, straw has excellent insulation characteristics. It can be used, alone or in a post-and-beam construction, to build straw bale houses.
In Japan, certain trees are wrapped with straw to protect them from the effects of a hard winter as well as to use them as a trap for parasite insects.
It is also used in ponds to reduce algae by changing the nutrient ratios in the water.
The soil under strawberries is covered with straw to protect the ripe berries from dirt, and straw is also used to cover the plants during winter to prevent the cold from killing them.