Cereals
Grasses grown for their starchy grain. An agricultural grouping rather than a taxon: every cereal here is a member of the grass family, but the family also contains sugarcane and the forage grasses, which are not cereals.
An agricultural grouping. Not a taxon and not claimed to be one — cereals span two families, pulses and oilseeds overlap, and the grouping is about what the crop is grown for.
What the grain is
A cereal grain is a caryopsis — a one-seeded dry fruit in which the seed coat is fused to the fruit wall — so what is threshed out is botanically a fruit rather than a seed. That is why the whole grain carries bran, germ and endosperm as distinct fractions, and why milling is a separation problem rather than a grinding one.
Hulled and free-threshing
The single most consequential division within the group is whether the glumes come away at threshing. Free-threshing cereals give clean grain from the combine; hulled cereals — spelt, emmer, einkorn, most of the small millets, and barley for some uses — need a dehulling step before milling, which is an extra machine and an extra loss. A hulled cereal and a free-threshing one are not interchangeable in a supply chain even when they are the same species.
C3 and C4 within one group
The temperate cereals are C3 and the tropical ones — maize, sorghum, the millets — are C4. That divides the group by water-use efficiency and by response to temperature more sharply than any agronomic convention does, and it is why cereal advice rarely transfers between the two halves.
Storage is where the crop is kept or lost
Grain is harvested alive and respiring, and the whole post-harvest system exists to bring it below the moisture at which moulds and insects can work. That is common to the group in a way that field agronomy is not: the same drying, aeration and hermetic principles apply from wheat to finger millet, and the differences are of scale rather than of kind.
Quality is defined by the end use, not by the crop
Cereal quality is specified against a process. Wheat is bought on protein and gluten for baking, durum on vitreousness for semolina, barley on protein for malting or feed, rice on head-rice yield after milling. A grower is aiming at a specification before they are aiming at a yield, and missing it moves the crop into a different market rather than reducing its price.
What this is not
- Pseudocereals — buckwheat, quinoa, amaranth — are used like cereals and are not grasses. They are held separately because their seed structure, milling behaviour and protein composition differ.
- Forage grasses are the same family grown for vegetative biomass rather than grain, which inverts almost every management decision.