COMMON GRASSLAND WEEDS: A BRIEF DESCRIPTION Crop protection: Grassland ✚ Docks are best controlled at the rosette stage, when leaves are a healthy green and not under stress. ✚ One plant can produce up to 60,000 seeds and these can remain viable for up to 80 years. ✚ Docks only provide 65% of the feed value of grass from the same area. ✚ Topping is not enough, as the deep roots allow them to recover and set seed. ✚ Intensive grazing or silage cutting doesn’t work, as viable seeds survive ensiling and digestion. DOCKS ✚ Nettles grow from seed or a portion of root, forming clumps with extensive root systems, and competing directly with grass. ✚ As nettle infestations grow, they make pasture unpalatable and reduce the grazing area available. ✚ Poached areas and open swards encourage nettles to establish. ✚ Once established, larger nettle beds are rarely controlled by one treatment and a follow up treatment is commonly required. ✚ Nettles are best controlled when young and actively growing, at around 15-25cm high. ✚ Spray coverage is particularly critical for this weed, typically use 300-400 litres water per hectare. NETTLES ✚ Ragwort is highly poisonous to stock, especially horses, when it is wilting or dead. ✚ As it germinates in bare ground or open sward, overgrazed or bare ground can encourage establishment. ✚ Uprooting ragwort is not a reliable option, as portions of the root will break off and continue to grow. ✚ Once sprayed, ragwort is more palatable to grazing animals. ✚ Do not graze until treated ragwort has died off completely and been removed from the field. RAGWORT ✚ Chickweed invades newly sown leys, or any gaps or bare areas left by poaching or other damage to established leys. ✚ Its rapid prostrate growth means chickweed competes aggressively with grass, leading to significant yield losses, especially when establishing new leys – particularly on nitrogen-rich sites. ✚ Try to avoid overgrazing. CHICKWEED ✚ Thrives in overgrazed land, particularly where drainage and fertility are poor. ✚ Rectifying field drainage and nutrient status will also help. ✚ Buttercup is mildly toxic and stock won’t graze it, reducing the productivity of pasture. ✚ Herbicide application should be applied before flowering. BUTTERCUP ✚ Established creeping thistle has extensive underground roots and competes strongly with grass. ✚ In the second year spear thistle can spread vigorously and can cover more than a square metre of ground – posing a serious threat to pasture productivity. ✚ Thistles can spread diseases, such as Orf, in sheep and lambs. ✚ Over-grazing or poor soil nutrition status, can encourage growth. ✚ Treatment later in the season can ensure that herbicides have a lasting effect. THISTLES ✚ Dandelion is common in low fertility or light soils, but has a high potassium requirement. ✚ It reduces the overall value of pasture if allowed to establish, as it competes directly with grassland. ✚ Herbicide application should be before flowering. DANDELION ✚ Spread by seed, it can quickly colonise open swards, and its deep and fibrous root system aid its spread. ✚ Repeated cutting at 4-8 week intervals may give some control. ✚ Cutting and then treating regrowth with a weed killer may offer additional control. RUSHES Please contact customer services: e: livestock@agrii.co.uk t: 0845 6073322 Please contact customer services: e: livestock@agrii.co.uk t: 0845 6073322 67 CROP PROTECTION 66 CROP PROTECTION Triad™ contains 50% w/w tribenuron-methyl. Spruce™ contains 400 g/l 2,4-DB. Polo™ contains 360 g/l 2,4-D + 315 g/l MCPA. Pinnacle™ contains 50% w/w thifensulfuron-methyl. All trademarks acknowledged. Under certain circumstances clovers may be checked when using clover-safe products. Please read the product labels fully. Use Pesticides Safely. For more information on these products please visit www.headland-ag.co.uk or contact your local distributor. Powerful grassland weed control • Young grass – Clover safe TRIAD™ + SPRUCE™ PINNACLE™ + SPRUCE™ • Established grass – Clover safe POLO™ • Versatile – Young or established grass – Non clover safe A growing business