Grassland management: May is a critical month for grassland management and has the ability to shape management for the rest of the summer. The rapid growth rates in recent weeks, following a difficult spring, is increasing the scale of this challenge.

There are lots of positives and, with the right management, there is scope to save high-quality baled silage that can be used to reduce concentrate requirements in late pregnancy.

For many, this will be achieved by splitting paddocks and confining sheep to a smaller area or skipping areas that have gone too strong for ewes and lambs to graze (grass height of 8cm to 10cm plus).

Taking these areas out of the grazing rotation and harvesting quickly will allow them to come straight back into the rotation and provide top-quality grazing for weaned February-born lambs or for ewes and lambs pre-weaning.

Where there is no scope to skip or split paddocks, it is important to offer ewes and lambs quality grass to achieve high levels of liveweight gain.

Where the sward has a high level of stem accumulating at the base of the sward, animals may need to be moved on when the sward has been grazed to 5cm to 6cm as opposed to the ideal situation of grazing down to 4cm. Sward quality can be improved by grazing paddocks with lower priority stock or creep grazing lambs ahead of ewes if possible and forcing ewes to graze lower.

The other option is topping, but it is important to ensure that you are topping to a worthwhile level of 3.4cm to 4cm rather than just running over the sward at a grass height of 5cm to 6cm.

Weed control was touched on last week with a few follow-on queries on suitable products. Teagasc launched a guide in 2015 for weed control in grassland management and this can be accessed at www.teagasc.ie/publications/2015/3619/Teagasc_Grassland_Weed_Control_Guide_2015.pdf.

Ewes on their back: The lift in temperatures and sunny weather is increasing the risk of ewes going on their backs. There has been a sharp rise in cases with dry hoggets, rams and ewes in strong body condition most at risk.

Some farmers report success in reducing the incidence by placing an implement such as a transport box, tractor trailer, roller, etc, in a field that allows ewes to scratch. In the long term, the best solution is shearing but with a backlog in some areas due to the delayed spring this may not be immediately possible. Dagging dirty tail ends has also been reported as a contributor to fewer incidences.

Nematodirus: The high-risk period for nematodirus was at the start of the month. However, a risk of re-infection or uptake of worms from younger lambs still exists, with lambs generally only developing a level of immunity when they reach 10 to 12 weeks of age. It is important that lambs at greatest risk (grazing low swards at a high stocking rate) receive treatment (or re-treatment as the case may be) with telltale symptoms being a characteristic yellow-green scour and lambs performing poorly. If left untreated, nematodirus poses a risk of lambs being stunted and taking significantly longer to finish.