Weed Control on Pasture and Silage Ground

Why It Matters

Effective, timely weed control preserves dry‑matter yields and silage quality, delivering measurable profit gains for pasture‑based livestock operations.

Key Takeaways

• Target docks at rosette stage with systemic herbicide for root kill.
• Apply dock sprays three weeks before silage cut for full efficacy.
• Use high water volume and low‑drift nozzles to ensure coverage.
• Eliminate perennial weeds a year ahead to simplify seed‑weed control.
• Choose clover‑safe products; many systemic herbicides are not clover‑friendly.

Summary

The episode tackles practical weed‑management strategies for pasture and silage ground, zeroing in on stubborn perennials such as docks, thistles, nettles and ragwort. Host Kieran Lynch and TP Wheeling’s Chris M explain why timing, product choice and sprayer setup are critical to protecting grass growth and silage quality.

Key insights include treating docks at the green rosette stage with systemic products like Dockstar Pro, then waiting at least three weeks before the silage cut to allow the chemical to travel down the 1‑metre taproot. High water volumes (200‑300 L ha⁻¹) and low‑drift or air‑induction nozzles improve leaf coverage, while hard‑water mitigation products such as Aquascope preserve efficacy. Systemic herbicides such as Tissile X Pro target creeping and spear thistles, and broad‑spectrum options like Forefront handle nettles, dandelions and ragwort when applied early.

Chris cites data: a 10 % dock infestation can cut dry‑matter yield by 10 %, and 30 % infestation can slash it by 30 %, also degrading silage fermentation and causing stem punctures in bales. Ragwort must be sprayed at the rosette stage; otherwise decay can take up to eight weeks, and grazing should be delayed until the plant fully decomposes.

The practical takeaway is to plan weed control a year ahead, eradicating perennials before reseeding, then using selective, clover‑safe products for annual weeds. Proper sprayer calibration, adequate water, and drift‑reduction nozzles translate into higher yields, better silage, and reduced chemical waste, directly boosting farm profitability.

Original Description

In a joint episode with Catherine Egan from the Beef Edge, we’re joined by Chris Maughan from TP Whelehan to explore practical weed control strategies.

Chris outlines a wide range of control options for common problem weeds, including docks, thistles, and ragwort.

We also discuss clover-safe sprays and how to plan weed control programmes when establishing or maintaining clover and multispecies swards. The conversation covers key technical considerations such as sprayer setup, nozzle selection, and how water quality can influence spray performance.

The episode wraps up with best practice advice on managing water quality and the safe disposal of chemical containers.

For more episodes from the OviCast podcast, visit the show page at:

https://www.teagasc.ie/animals/sheep/ovicast-sheep-podcast