| 2014-02-06 |    |
Target ‘New Ponds’ in Grass Fields for Remedial Action
The appearance of new ponds in grass fields after record-breaking rainfall may be a sign of poor drainage due to compaction or failing land-drains, says Rod Bonshor, general manager for Oliver Seeds.
“The lie of the land generally dictates where water is likely to collect when the soil is saturated,” says Mr. Bonshor. “But to ensure grass in low-lying areas is not submerged for too long, it is essential to maintain drains and ditches. It is worth noting the position of new ponds while they are so visible.”
Growth will be delayed if grass is submerged for too long
Take action
Using sward
lifters, sub-soilers and aerators to break up compaction and to
allow air into the soil, when conditions are right (ie, not when the soil
is water-logged), can also make a considerable difference.
“The benefits of aerating grassland is clear on one farm in Nottinghamshire which experimented last year – aerating one half of a wet field and not the other. Today the treated half can be walked on easily and has no surface water, whilst the other side is a potential mud bath.
“Aerated grassland is also quicker to dry and warm up and grass will start growing sooner,” says Mr. Bonshor.
Moss
problems
Some farmers are reporting a high incidence of moss, even in relatively young
leys.
This is an indication that conditions are not ideal for growing grass, as moss colonises gaps where grass is not growing well or has died.
Fields like this will need aggressive harrowing with stiff tines this spring to remove it. However, it is also essential to correct the underlying problem to encourage healthy grass growth or the moss will return.
Moss thrives in low nutrient, acid conditions, shady areas and wet soils. Taking a soil test can indicate if poor fertility is to blame, and it will be obvious if shade is the cause. If it is neither of these, poor drainage is likely to be the problem.
Lack of nutrients
Reseeds established last autumn that did not receive any fertiliser,
slurry or FYM at sowing, are now looking decidedly yellow and undernourished,
says Mr. Bonshor.
This will delay sward recovery and growth when the weather does improve, and may call for a different approach to seedbed fertilisers for future sowings, especially on the hungriest soils.
“There is no doubt that the recent heavy rainfall can denude the soil of nutrients especially nitrogen. In new leys where the root zone tends to be in the top 50mm of soil, nutrient deficit shows as reduced growth, leaf yellowing and dieback, which expose the plant to secondary disease attack and death.
“I have seen this in fields of Italian ryegrass sown in late August on light, stony soils following winter barley, with no seedbed fertiliser. By mid November, these fast growing grasses were looking decidedly sick.”
Walk all grass now
“This year more than ever it is vital to go out and walk all grass in
the next two weeks, and then make a plan for each field – when to apply
fertiliser, when to turn-out, how to graze, how much to shut up for
silage, and what other remedial actions are needed,” advises Mr. Bonshor.
“Farmers that do nothing this spring are likely to see much reduced
grass yields and a potential forage shortfall.”
