Agriculture Victoria livestock and land management extension officer Neil James said returning stock too early may result in damage or death of deep-rooted perennials such as phalaris, cocksfoot and fescue.
“The loss of perennial pasture is primarily caused by over-grazing, but when combined with extended dry periods, pasture decline can intensify,” Mr James said.
“Perennial ryegrass, however, rarely survives prolonged dry periods, regardless of grazing pressure.
“Many pastures are already under stress due to the prolonged dry conditions. Late season rainfall will have triggered some green leaf growth.”
Repeated grazing of these new shoots can deplete a plant’s root reserves, ultimately leading to plant death.
“Ideally, livestock should be held in containment until pastures have grown sufficient leaf area to maximise photosynthesis and rebuild their root reserves,” Mr James said.
“This may take four to six weeks following rain or longer, depending on the starting condition and temperature.
“Where stock containment is not possible due to the onset of lambing, or excessively wet conditions, farmers might consider containing stock in a paddock corner or using part of a laneway to form a small sacrifice paddock.
“Keeping the area small minimises paddock damage and reduces energy requirements of stock when compared with searching for feed over larger areas.”
Mr James said resowing perennial pastures was extremely expensive, often exceeding $200/ha, and producers planning to sow new pastures are encouraged to review how those species have performed in environments similar to their own.
“The Pasture Trial Network, developed and hosted by Meat & Livestock Australia, compiles data from independent trial sites assessing a wide range of pasture varieties.
“It can be used to compare the performance (seasonal and total dry matter production) of tested varieties of legumes and grasses.”
For more information about perennial pastures, visit the Agriculture Victoria website.