Clover - Why Now?
Ever thought of increasing the diversity in your swards? This can be simply and profitably done across the whole farm over 3 years adding to the health of the soil, animals and consumers as well as reducing losses to water and emissions to the atmosphere. Lane Giles, ASSAP Advisor tells us more.
White clover, common in Mediterranean regions, holds moisture close to the ground and helps retain carbon dioxide (increasing photosynthetic efficiency) which would otherwise escape more easily from the open canopy of grass-only swards. It also has rhizobia bacteria in nodules on its roots that “fix” nitrogen from the air and make it available for plant growth. The extra diversity in the sward also leading to greater microbial activity in the soil.
Livestock like diversity in their diet. Cows grazing grass-white clover swards eat more, producing in the region of 20-50 kg extra milk solids per year, found to be worth an extra €12,000 in milk sales per 100 acres at Darrara College Clonakilty. Recent research in Clonakilty has shown that white clover can increase herbage production by 1 – 1.5 tons DM/ha/yr and can contribute to the reduction of N fertiliser application thus improving N use efficiency.
Research in Moorepark has shown conclusively that white clover in the sward can replace 40% chemical nitrogen (100 kg N/ha) and not affect herbage production compared to a grass-only sward receiving 250 kg N/ha. This saving of 80 units N/acre is worth about €4000 per 100 acres.
- Aim to have weeds under control and soil in good health, balanced for nutrients and lime ahead of sowing.
- A programme of reseeding 10% per year and over sowing 30% per year can achieve the target of 20-25% average annual sward clover content within 3 years.
- Reseed at 1.5 - 2 kg clover per acre sowing in April – June. Sow at a depth of 1 cm or less, rolling afterwards. If a paddock drops below 10 - 15% clover it may be one to consider oversowing. Oversow at 2 – 2.5 kg clover per acre. For best results bare the paddock first before surface seeding and rolling just ahead of rain.
- Grazing off covers of 700 - 900 kg DM/ha helps the clover seedlings to establish.
- The extra growth comes the following year, approximately 8 kg DM/ha/day is grown between mid-April and end of September. Reduce chemical nitrogen from the third rotation in early May when the clover increases in the sward.
Key management techniques
- Avoid letting animals into high clover contents hungry or else restrict the amount they consume. This can easily be done by letting all cows into the paddock together so each gets a comparable amount.
- In Autumn aim to graze off paddocks with least clover first, these will grow more grass over winter and can be the first to graze in spring. Graze those with the most clover last in November coming back to them last again in spring.
- Aim to avoid poaching.
- Flexibility is the key, managing according to clover content, as well as total cover.
Most of all, enjoy the diversity!
In this short video clip Lane Giles talks about why you should use White Clover