Corn ground beetle

Damage

The larvae chew young leaves at the 2–3 leaf stage and during tillering. Damaged plants have a characteristic frayed look, like a bast scrubber.

When to look

The beetles appear while the grain of winter wheat and other cereals is forming, and in large numbers at the milk ripeness stage. They feed on the grain until harvest begins.

No rate and no spray timing here: both come from the label and the register.

Agronomy

• Agronomic measures play the main role: sowing winter crops at the latest acceptable dates, a scientifically based crop rotation, harvesting at optimally early dates and within a short period, stubble cultivation and early ploughing. Timely tillage also reduces the build-up of the pest.
• Control measure: two-stage (swath) harvesting of the grain crop with quick threshing of the swaths.
• Stubble cultivation and early deep ploughing protect against this pest, as does sowing cereals after non-stubble preceding crops.
• To prevent harm from the cereal ground beetle, winter wheat is grown after the best preceding crops: bare fallow, maize for green fodder and silage, forage legumes, peas.

Yield loss

One beetle can damage up to 50–60 grains in a season.

Migration

It moves from fields with sprouted volunteer plants to straw stacks.

Favourable conditions

• It develops and causes damage most of all in fields of winter cereal crops grown after small-grain cereal predecessors.
• Recently, hot weather from late June to early August has somewhat held back the development and harmfulness of ground beetles.
• It is dangerous primarily in the zone of significant damage: on winter crops sown after grain predecessors, in low-lying areas, in places where grain was lost after harvest and near straw stacks.

Where it is found

It causes damage in almost all oblasts of the Steppe and Forest-Steppe, including some western regions, and in places also in the Polissia zone, primarily in Volyn oblast.

Every fact rests on a quote from its source, and each quote was checked against the page it is printed on.

1. Зайцева І. А., «Сільськогосподарська ентомологія. Курс лекцій», навчальний посібник, 237 с. · Дніпровський державний аграрно-економічний університет, Дніпро, 2021 · p. 102, 111
2. EPPO Global Database · European and Mediterranean Plant Protection Organization
3. Прогноз фітосанітарного стану агроценозів України та рекомендації щодо захисту рослин у 2025 році · Держпродспоживслужба, НААН, НАН · p. 28, 29
4. Photos: Roman, iNaturalist, CC BY 4.0 · Udo Schmidt from Deutschland, Wikimedia Commons, CC BY-SA 2.0