Grassland management

General comments
Output of a grass seed mixture will be optimal in case of proper grassland management. This means good soil preparation, sufficient nitrogen input per hectare per year and sufficient levels of potassium and phosphor in the soil. It is recommended to stop fertilizing in early September, so that the grass can harden and improve the mixture’s winter hardiness.

 

To ensure a high sward density and good clover content it is recommended not to harvest too heavy cuts, in other words no more than 3500 kg dry matter/ha This will result in higher energy levels in the grass or silage, higher dry matter intake and a faster regrowth of the sward. Before winter, all pastures need to be cut to a grass height of about 7-8 cm. For this, use a grass-topping machine when the grass growth has stopped in the autumn.

 

Management

Soil:

  • Before starting soil preparations, soil samples at 10-25 cm need to be taken to obtain information about the soil fertility
  • If the field is covered with noxious weeds or quack grass, these should be treated first with a controlling measure, such as Round-Up, and wait for 10 days before ploughing.
  • If the field was used as grassland before, the field must be rotor tilled.
  • Plough the field properly and allow the soil to become firm. Therefore, ploughing needs to be done some weeks before sowing or otherwise use a plough packer while ploughing.
  • If necessary, the field needs to be levelled out in order to make it flat.
  • Before sowing, the seedbed needs to be prepared properly. This can be done also in combination with the seeddrilling machine.


Fertilization:

  • Before ploughing, organic manure can be applied or 15-25 tons slurry per hectare after ploughing. It is important to mix the slurry well before application.
  • Additional fertilizer after ploughing can be given in the form of artificial fertilizer. Young grassland plants need sufficient phosphor during the establishment period. Low phosphor levels in the top layer of the soil may lead to slower growth.
  • Fertilize according to the soil analyses and also maintain the magnesium (Mg), sulphur (S) and sodium (Na) levels in the soil.
  • The first cut per hectare will need approximately 80-100 kg Nitrogen, 100 kg P2O5 and 140 kg of K20.
  • In case the grass seed mixture contains White clover it is recommended to limit fertilization during the first year. This will enable a well-balanced establishment of grass and clover. While nitrogen fertilization should  be kept low, it is important to maintain good levels of P2O5 and K2O, as clover is very vulnerable to any deficiency in P2O5 and K2O levels.

 

Sowing:

  • Seed rate: 40-50 kg per hectare.
  • Sowing machine: for best results use a grass-seed drilling machine. If not available, a cereal drilling  machine can be used, but take the following into account:

         - Shallow drilling at 0.5-1.0 cm. Deeper sowing will cause troubles for the establishment of the clover 

            and timothy in particular.
         - Use a specialised grass-seed drilling machine (Vredo, Brillion, etc.)
         - In all other cases: sow the field square (north>south and east>west) with the cereal drilling machine. 

            Otherwise the distances between the rows will be too big.
         - Sow only in a clean field without weeds. Make use of a false seedbed if a high weed pressure on the  

            field is expected.

         - After sowing: tackle the broad-leaved weeds. These will disturb good establishment of the grass.
         - Do not sow in very hot periods or periods without rainfall after sowing.


Harvest:

  • Start the first cut with light grazing during 1 or 2 days, or with a light first cutting of 2000-2500 kg/ha. Cutting height 6-8 cm, providing better regrowth.
  • Avoid heavy cuts of more than 3500 kg dry matter/ha.
  • Start grazing when the grass has achieved a length of 15-18 cm, being 1700-2100 kg dry matter/ha.
  • The field period after cutting should be as short as possible: maximum of 4 days.
  • Make silage if the wilted grass contains about 30-40% dry matter.
  • Use a silage additive if the ensiling grass contains less than 25% dry matter.
  • Fill up the clamp with small layers and compress the product carefully.
  • Close the silage clamp as soon as possible and cover with plastic and soil.
  • Control the silage clamps weekly for damage. Small holes, caused by rats or mice, allows oxygen to penetrate in the silage that will cause serious quality deterioration.

 

Cleaning cuts
If pastures are grazed frequently it is the best to use the grass for a silage cut after two cuts of grazing.  Cows will then become less selective in the next cut, resulting in a better intake by the animals.

 

Pests
Keep moles and mice under control (if allowed). Molehills increase the crude ash content in the silage and will cut down the feeding value per kg dry matter. Mice will damage the root system of the sward resulting in reduced growth or even the death of grass plants. Particularly Leather jackets (crane fly grub/Tipula) cause
problems in the late summer and early spring on grassland. The larvae eat the grass plant roots, resulting in extra winterkill and the establishment of unwanted grass species (Poa annua). Check the pastures and leys in October/November to make sure that larvae concentrations are not higher than 100 per m2. Simple testing methods using saltwater can be used. If larvae concentrations are lower than 100 per m2, chemical measures are not recommended. If the concentration of leather jackets is higher than 100 it will be necessary to apply chemical measures in the autumn. If no control measures are taken, the damage in spring can be very high,  resulting in less dry matter yield per hectare. Applying chemical measures in spring is unwanted due to risk  of killing young birds.

 

Weed control
Be alert for noxious weeds. Broad-leaved weeds are usually easy to control with 2,4-D, MCPA or MCPP. Rumex, obstusifolius / Docks / Stumpblättriger needs an integrated weed control program lasting several  years. We will pay extra attention to measures to control this problem weed.


Characteristics of Rumex:

  • Produces a large number of seeds per plant which are fertile just one week after flowering in the period June - October
  • Rumex seeds can survive in the soil for up to 70 years
  • Rumex can survive in manure and in slurry

 

Main problem:

  • Rumex spreads rapidly in a pasture. It is unpalatable to cattle and horses and has a negative effect on the feeding quality by increased crude ash and crude fibre content in the silage.


General control:

  • Avoid flowering of the plants to avoid new seeds.
  • Avoid too high fertilization levels.
  • Store slurry at least a couple of months and mix the slurry weekly. This will kill many Rumex seeds.
  • Do not use compost contaminated with Rumex.

 

Mechanical control:

  • Frequent mowing to prevent plants from producing new seeds.
  • Remove young plants by hand with special equipment, Rumex fork /Ampfergabel, at the end of June.
  • Use over-seeding on the open spaces in the sward.
  • In case of new sowing: make use of ‘false seedbed’. This means: preparing the soil, waiting 5-6 weeks and then make a new seedbed, followed by sowing. This practice will kill many young Rumex plants.

 

Chemical control:
Best period for chemical control is May-June and in October. There are several chemicals for controlling Rumex. Ask your local supplier about this. Well-known chemicals are:

  • Harmony; 30 grams per ha.
  • Starane; 2 litre per ha.
  • Hoestar; 60 grams per ha.
  • Banvel M; 8 liter per ha.

 

Some comments:

  • use fine spraying nozzles for maximum leaf contact
  • do not cut the grass within 7 days of spraying
  • spray only when the Rumex is growing well, e.g. after a period of rainfall.
  • rain within 24 hours of application will reduce the effect of the chemicals.
  • spray when daytime temperatures are around 18-20 ºC.
  • alternatively, a Round-Up stick can be used to control plant by plant. Although very time consuming, this method can be very successful.


If farmers are patient and willing to invest a number of years to control Rumex it will result in clean pastures and leys.