Multi-species swards are often thought only suitable for good quality, dry land. However, by selecting species that can better cope with wet or dry conditions, we can formulate different mixtures to suit different soil types.
A good starting point is a mixture of species that will perform on a range of soil types like perennial ryegrass, white clover and ribwort plantain. Once we have this foundation, the mixture can be tailored towards dry or wet soils.
In particularly light, dry soils, adding species like festulolium, cocksfoot, lucerne and chicory will help keep the sward productive during prolonged dry periods.
On the other hand, in heavy, wet soils, species like timothy, meadow fescue and plantain are well equipped to cope with such challenging conditions.
Multi-species swards can be sown any time between late spring and early autumn. Ideally, soil temperatures should be around 10°C for successful germination and establishment.
Optimum soil fertility is required to maximise production. Soil fertility guidelines for grass swards regarding soil pH, P and K levels should be followed for multi-species swards.
The conventional method of burning off the old sward, ploughing etc.… is the most effective way to establish a new multi-species sward resulting in a greater abundance of sown species and fewer weeds. This is important as we cannot apply any herbicide on multi-species swards as the herb portion is not resistant to herbicide.
The small seeds of clover, plantain and chicory require shallow sowing (~1 cm).
Oversowing legumes and herbs into an existing grass sward represent an economical alternative method for establishing multi-species swards. It is critical, however, to address any weed issues in the field before oversowing. Alternatively, choose a field with a low weed burden in which to oversow.
Species like white clover, plantain and chicory should be oversown at between 1.5 and 2kg/acre each.
As with any oversowing operation, it is important to reduce competition from established plants by sowing into an open sward in which soil-seed contact can be made, and light can reach the new seedlings.
This can be achieved by oversowing after a silage cut or after tight grazing. Continuing to graze for 7 – 10 days after oversowing can further reduce grass growth and promote germination and establishment of the new seeds.
Once there is good establishment from the grass, legume and herb portions of the mixture, there should be minimal opportunity for weeds to establish.
The similarity in growth habit of herbs like plantain and chicory to common grassland weeds like docks, means that once these species get established, there is no space in the sward for docks and other broadleaf weeds. Small outbreaks of weeds can be spot-sprayed if necessary.
For more information on selecting the right mixture for your farm, call Thomas Moloney, DLF 087 396 1265
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