Invasive grass species found in UK wildflower mix, warns Teagasc
A highly invasive blackgrass weed has been discovered in a commercial wildflower mixture from the UK, Teagasc has warnd.
Teagasc made the discovery having grown a mix which originated in the UK. They have not named the product used.
It was grown in "an experimental plot" at their Oak Park base in County Carlow, and have taken action to destroy the entire field margin where it was grown.
Blackgrass is described by the agri-experts as "a particularly pernicious weed of cereal crops".
They warn that if this weed is widespread in mixtures which were planted on farms, schools, gardens, and amenity areas across the country it poses "a huge risk of contamination to tillage crops" and the Irish tillage industry.
Teagasc made the warning against the background of the increasingly popular trend of wildflower patches in gardens and meadows to provide colour and feed for pollinators.
The wildflowers seed was sown last Autumn in a field margin in Oak Park, which is predominantly in tillage. It was done in line with Teagasc's policy of increasing habitats and improving biodiversity on all of its research and college farms.
On inspection by the Teagasc farm manager in Oak Park, John Hogan in recent days, it has been noted that this mix was contaminated with blackgrass which is a particularly pernicious weed of cereal crops. If left uncontrolled it can produce up to 6,000 seeds per plant. These seeds will spread quickly by machinery or on plant material.
John Spink, Head of Crops, Environment and Land Use Programme in Teagasc said: “Blackgrass is widespread in the UK where it is also resistant to a wide range of herbicides and very costly to control, in some instances requiring the destruction of crops.”
John added; “If the wildflower seed has been imported from the UK then resistant blackgrass may have been imported with it. The blackgrass is just beginning to flower and because of the risk of spread of seed into neighbouring crops, unfortunately, this field margin has had to be destroyed”.
Such wildflower mixes are frequently used in domestic and amenity situations. Michael Hennessy, Head of Crops Knowledge Transfer in Teagasc said; “We strongly encourage anyone with such seed mixtures sown to inspect the area and if they notice blackgrass, which has a narrow dark purple to black seed head, to remove it immediately before seed is formed and can spread into any neighbouring crop areas.”.