The highly invasive blackgrass weed was found in a commercial wildflower mixture that was grown in an experimental plot in Carlow. 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.
In recent years, Teagasc has had a policy of increasing habitats and improving biodiversity on all of its research and college farms. In Oak Park, which is predominantly in tillage, this has included establishing new hedges and field margins on cultivated fields. A range of field margins, from native grasses to mixtures of grasses and wild flowers, have been established. Researchers have been monitoring these field margins for beneficial insects and their impact on insect pests in adjoining crops. Additionally margins of native grass mixes of cocksfoot and timothy have been particularly effective in stopping sterile brome, which is a grass weed in cereals from spreading from the hedgerow into the crop.
One such field margin planted last autumn was a diverse mix of wild flowers and grasses. 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.
Blackgrass is widespread in the UK where it is also resistant to a wide range of herbicides and very costly to control. For more on Blackgrass herbicide resistance see here and a video of resistance testing in Oak Park here. And there is a series of videos which will help to identify grass weeds in the field here.
Blackgrass moves from heading in to flowering and seed set quickly. A blackgrass plant may have some heads which are flowering while at the same time others shoots on the plant may have finished seed fill and re shedding seeds for next year. If blackgrass is present and flowering, assume seeds have been set. Immediately remove the plants, and ideally remove the entire crop. Burn or dispose of this material off farm. Apply glyphostae to the regrowth to ensure all plants are controlled. Shallow cultivate a number of times this year and ensure to thoroughly inspect the area for the next 3 years to ensure there are no more blackgrass plants emerge.
Teagasc has produced a video here of the problem wildflower mix in Oak Park and other videos around identification of grass weeds (blackgrass) are also available on the Teagasc Crops YouTube channel https://www.youtube.com/c/TeagascCrops/videos
There is huge interest in farmers and citizens who want to plant "wildflowers" to improve biodiversity and food for the bees. This increased interest has resulted in these seeds being imported from various different sources in Europe and further afield. Wild flower seed is not covered in the seed certification legislation – therefore there are no minimum standards for germination or purity. Where wild flower seed is traded the provisions of Article 5 of the Ornamentals Directive 98/56/EC may be used– see below.
Some of the species used in these mixes may fall under legislation for Wild Flora and Fauna Ornamental, Vegetables or Forage crops.
Wild Flora and Fauna legislation, Council Regulation (EC) No 338/97 does specify certain protection of species of wild fauna and flora by regulating trade in those species, but doesn’t set quality or certification standards.
Some seeds (Chicory and Sheep’s Parsley) are included in the legislation covering seeds of Vegetables see Article 2 and Annex II of Directive 2002/55/EC. Minimum standards apply for germination and purity.
Sanfoin (Onobrychis viciifolia) is covered in the fodder plants directive – Directive 66/401/EEC. Minimum standards apply for germination and purity.
Ornamentals Directive 98/56/EC Article 5
Teagasc do not recommend sowing wildflowers IF the aim is to improve biodiversity ( National Parks and Wildlife Service have expressed concerns on potential negative interaction with native biodiversity). A couple of points about wildflowers:
A zero tolerance should be taken to contamination of blackgrass in seeds sold to tillage farms, or indeed into Ireland. This must come from and be enforced through the Department of Agriculture with the full co-operation of seed suppliers both in the agricultural industry and beyond. A strengthening of legislation of wildflowers seed production and importation is necessary and a voluntary standard should be in place while the legislation is being drafted/enacted.
Crops are approaching the flag leaf fully emerged. In general the upper canopy seems to be relatively clean from septoria however yellow rust seems to be still an issue in some susceptible varieties. Most crops will receive the second fungicide on the flag leaf early next week.
As with all crops the recent rain has helped crops recover but the cool weather has restricted growth some what. Crops are at the flag leaf to head emerging stage and the final fungicide will be applied over the next couple of weeks depending on growth.
Advanced spring wheat is at growth stage 31 and are approaching growth regulator timing. Disease levels are low.
Recent weather conditions are favourable for the spread of chocolate spot in spring beans. Earlier sown crops are approaching flowering and will soon be at the correct timing for preventative disease control. Despite cool weather bean weevil notching is evident in many crops but most are now beyond the growth stage where control is needed.
Recent broken weather has both helped and hindered spring barley. Crops have grown well and the earlier sown crops are at GS 30. Disease levels were relatively low till now but there have been a few reports of rhynchosporium in recent days. Tank mixes will be an issue for some growers as spraying opportunities have been scarce with some advanced crops still awaiting weed control.
Spring oats are growing strongly despite the weather. Crops are approaching GS30 and crops are free from foliar disease so far.
Most maincrops will start to emerge over the coming week and so are at the ideal stage for pre-emergence weed control. The recent wet weather has made soils moist enough for the various herbicides to work perfectly, however there are reports of ground conditions becoming very soft in places which is making travelling on the fields difficult.
Growth in fodder beet has been slow and first herbicide application were delayed as a result of cool conditions. Herbicide strategies have been altered and so it is important to tailor herbicide mixes to crop size and weeds present.
In light of the recent change in public health measures for COVID, we are pleased to confirm that we are planning to run a Tillage Event at Oak Park, Carlow from June 29th to July 1st.
In order to adhere to health restrictions, attendance will be by pre-registration only. This will allow us to accommodate individual groups of up to 14 attendees, at designated time slots through each of the three days.
The content will be the same for each day, with research updates on a range of crops including; winter and spring barley, winter wheat, oats, oilseed rape and beans. The Crops research trial programme will be on view with key topics presented at multiple information points across the Oak Park campus, covering up to date research and KT activities on the primary issues affecting the tillage sector today.
Further details including registration access will be available on Teagasc.ie/events and on all social channels in the coming days.