In barley agronomy, a distinction is made between total tillering, which takes into account all stems, and productive tillering, which represents the number of stems with a fully formed spike. For spring barley, the typical range of productive tillering is 2.5–3.0 stems per plant, although depending on agronomic practices and environmental conditions, these values can vary from 1.39 to 3.6 and higher.
Tillering development depends directly on the seed planting depth and the availability of light, moisture, and nutrients. Barley is capable of tillering more intensively than many other cereals, but under drought conditions, excessive shoot formation can become a negative factor, leading to the inefficient consumption of resources for non-productive stems.
Productive tillering determines stand density and allows for reduced seeding rates when breeding highly tillering varieties. This indicator shows a negative correlation with grain weight per spike and thousand-grain weight, as well as a moderate correlation with crop lodging resistance.
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Tillering.