Managing dominance in multi-species swards

To get the most from a multi-species sward, it’s important to prevent any one species becoming too dominant. When a single species takes over, biodiversity declines, forage quality can suffer and the risks from pests, diseases and nutritional imbalances increase.

Managing dominance is not a one-off activity. It needs regular monitoring and flexible management to keep the sward balanced, productive and resilient.

Spotting dominance issues early allows timely, low-cost interventions. 

• Visual assessments – walk fields regularly and note changes in species presence and ground cover 

• Botanical checks – use simple counts or surveys to track proportions of grasses, legumes and herbs 

• Record keeping – repeat photos from the same points through the year to monitor trends over time 

Changes in dominance often happen gradually, so consistent monitoring is key.

Choosing the right grazing strategy is one of your most powerful tools for controlling dominance. 

Rotational grazing – short grazing periods followed by adequate rest – can enable slower-growing species to recover and prevents selective grazing pressure. 

Match grazing intensity to the sward. Overgrazing favours aggressive species, such as perennial rye-grass, while under grazing encourages selective grazing, allowing preferred species to dominate. 

Where one species is clearly dominant, short periods of higher grazing pressure can help weaken it and restore balance.

Cutting can be used strategically to rebalance a multi-species sward. 

• Cutting height – slightly lower cuts can suppress tall, vigorous species and support lower growing plants such as clover 

• Cutting frequency – cutting every 4–6 weeks during the growing season prevents dominant species from setting seed 

• Timing – cutting just before flowering reduces vigour in dominant plants and gives less competitive species a chance to compete 

Plan cutting to support both sward balance and forage quality.

Soil fertility strongly influences which species dominate. Balanced fertility supports weaker species and helps maintain diversity. 

Keep nitrogen inputs moderate (typically no more than 50–100 kg N/ha/year) as excess nitrogen strongly favours grasses and suppresses legumes and herbs. 

Test soils every 4–5 years and try to maintain adequate phosphorus, potassium and key trace elements. 

Overseeding is best used to restore underrepresented species after grazing, cutting or light cultivation. 

A standard overseeding rate for herbal leys is 5–8 kg/ha, depending on existing sward composition and target species. 

Focus on specific species such as white or red clover, chicory and plantain. 

If performance or diversity has declined significantly, a partial or full reseed may be required.  

A standard seed rate for a full reseed is 30–35 kg/ha, depending on soil type, seed size and mix complexity. 

Reseed mixes typically include a combination of grasses, legumes and herbs, in the following ranges: 

• Grasses: 12–18 kg/ha 

• Legumes: 8–12 kg/ha 

• Herbs: 3–6 kg/ha 

Use tailored seed mixes to suit objectives such as drought tolerance, productivity or biodiversity. 

Dominant species can encourage pest and disease pressure. Use an Integrated Pest Management (IPM) approach and try to identify and manage problems early to protect sensitive species. 

Common risks include: 

• Clover – clover rot and red clover sickness 

• Chicory – root rot and downy or powdery mildew 

• Lucerne – fungal diseases such as Phytophthora