Strategies to combat sorrel, buttercups and similar
After cutting, show courage and take targeted action against problem weeds in grassland between uses.
After cutting is a particularly favourable time to target problem weeds in the grassland. Farmers should take the following into account as they tackle weeds:
Mechanical and chemical means can be used to combat weeds
After-treatments are required at times – farmers need to be flexible regarding the application period
Toxic plants have negative effects on farm animal health and performance
Observe waiting times; use Simplex in spring with subsequent grazing only
Remove toxic plants such as common ragwort once they have died off since animals lose their aversion to toxic plants when feeding if the plants have been treated
Sorrel is widespread on grassland. A DM yield loss of 5% is to be expected with just one sorrel plant per square metre. Farmers achieve an optimal control time (20% of sorrel flowering stems sprouted) using a full rose across sufficient leaf mass. If farmers declare war on sorrel with Ranger, for example, they will kill chickweed and dandelion at the same time.
Rough calculation to indicate cost-effectiveness of sorrel treatment
DM yields of some 50 dt DM/ha are expected for the first cut.
5% = 2.5 dt DM/ha loss
At 6.5 MJ NEL/kg DM = 1,625 MJ NEL/ha
= 518 litres less milk per 1 hectare
At 32 ct/kg milk = €165/ha
As a comparison: Use of Ranger about €90/ha + application
Poisonous effect of meadow buttercup
Weeds in grassland cultivation not only compete for nutrients and space, but they are also poisonous. Many underestimate the meadow buttercup (Ranunculus acris). It contains the toxin protoanemonin.
Characteristics of the meadow buttercup
Takes two months to become non-toxic in silage
Use in hay reduces toxic load
Toxic load is highest during florescence
Symptoms and problems
Mucous membrane irritation; can damage kidneys and mammary glands during excretion
Effects on the central nervous system leading to paralysis, cardiac arrest, death
Damage to the liver which leads to intolerance to sunlight
Animals avoid the plant in meadows, but not in silage
Symptoms such as loss of appetite, drooling, diarrhoea and a reduction in milk yield are often not associated with intoxication
Overseeding after herbicide has been used
Overseeding after herbicide use is essential to cover patches with high-quality grasses before more grass weeds and other weeds take over such parts. As a plant which requires light for germination, sorrel has no problem spreading across bare patches. Farmers should therefore take preventive action with continuous overseeding to ensure a dense sward and prevent patches. However, patches should only be overseeded after weeds have died off completely to ensure grass seeds come into contact with the soil. Damage to the seedlings is not expected at this time – clover plays a special role in this respect.
Overseeding carried out in early spring has generally exceeded the four-leaf stage and is relatively robust against herbicide use. Farmers should pay attention to suitability for locations and performance of the varieties used to ensure they choose the right seed mixes. The mix is particularly suitable for overseeding Plantinum Intensiv . It contains certified top varieties of late-flowering German rye grass. These varieties ensure a high cutting frequency with maximum harvesting elasticity. The combination between competitive German rye grass and subsequent intensive cutting and pasture use helps grass to become established in the old sward and ensures overseeding succeeds.
Tip from the experts
Farmers can minimise the risks of overseeding by seeding at several different times. An ideal solution is to sow 5 kg/ha of seed in the spring, during use and in the autumn.
Tips for grassland cultivation
You can obtain tips for successful grassland cultivation directly from us.