Maximising home-grown feed

“Bought-in feed is the most expensive source of high-quality feed,” Bec told farmers at Pasture 101 workshops in northern and southern Victoria.

“The balance is utilising as much home-grown feed as possible.”

Despite the cold growing conditions and poor soil moisture in many dairy regions in southern Australia, a soil test on good paddocks where results preclude the need to apply extra fertiliser, can either save the farmer money, or enable them to decide if it is worth fertilising traditionally poorer production areas on the farm.

Jake Frecklington, from DLF Seeds, said the cost of a soil test — at $200 — was the best way to identify paddocks for summer cropping and what pasture varieties to sow for spring and autumn grazing.

In a recent Dairy Australia webinar addressing the ongoing drought, Jake said pasture growth has been slow due to the lack of rain and cold conditions in Gippsland, south-west Victoria and South Australia.

While rain in some regions has lifted the soil moisture profile and raising hopes for spring growth, there have been other negative issues affecting pastures.

“Many farmers didn’t sow paddocks in the autumn, and newly sown paddocks have been slow to establish or may be dead,” Jake said.

“Where it has rained and where pastures are growing, many are affected by the cold, so we’re getting a green drought in some areas.

“There’s also been pest pressure from red legged earth mites, snails and crickets.”

Jake said he had also seen, and heard about, animal health issues across the south-west Victoria and Gippsland regions.

“Nitrate poisoning has occurred in some herds.”

He said the variable and challenging conditions across fodder growing regions would result in expensive and short supply in this season and potentially in successive seasons.

“Queensland is wet, half of NSW is wet and the other half is in drought, Victoria and South Australia are dry. Fibre is hard to source or is very expensive and expected to be expensive for the next season,” Jake said.

“It’s important to look at how to grow pasture and feed on the farm.”

The on-farm pasture workshops led by Bec enabled participants to learn about how ryegrass grows and grazing management for production, managing residuals and creating a feed wedge.

When choosing which paddocks to prioritise for fertiliser and resowing, a soil test can help decision making. It is also an affordable investment for decision making.

“The emphasis is on producing quality feed to graze,” Bec said.

“The cost of a soil test on your best paddocks can impact positively on the cost of applying fertiliser, for the reward of high-yielding and dense pastures.”

Bec said dense ryegrass pastures benefited from grazing that encouraged the production of daughter tillers.

In ryegrass paddocks, encouraging the growth of daughter tillers enables increased plant density. As the daughter tillers develop their own roots and leaves, becoming independent plants, pasture becomes thicker and higher yielding.

“Grazing should be at the 2.5 to three-leaf stage,” Bec said.

“The plant is more palatable and the stem is less fibrous.”

After grazing, sunlight was able to get through to the base of the plant, where the tillers were growing as offshoots.

“You need daughter tillers for dense pastures,” Bec said.

If the grazing rotation between paddocks is too long, pastures grow too much stem.

“A taller and bigger stem has more fibrous content and cows don’t like it, so they’ll eat less,” Bec said.

“If the cow is eating more fibrous plants, this also fills up her stomach so she eats less better quality feed.”

A tall residual will also mean the daughter plant has to grow taller to access sunlight.

Daughter tillers start growing off the plant at the two-leaf stage.

Daughter tillers producing thicker pasture means farmers can then push out the time between grazings.

“At the three-leaf stage, you get 40 per cent more growth of the leaf surface of the plant,” Bec said.

“If it takes 45 days to grow the plant to the 2.5 to three-leaf stage, then you have a 45 day rotation.

“This growth is, of course, affected by temperature, moisture, and hours of daylight and sunlight.

“Therefore, rotation can be out to 70 days during winter. In mid-spring, it should be down to 18-21 days.

“As the weather warms up and days are longer, and with sufficient soil moisture, residual growth turns into silage and hay.”

As grazing rotation shortens with longer days, Bec said farmers needed to be mindful that pasture needed to get past the two-leaf stage before cows were allowed on it.

“As the plant is growing the second leaf, it is reliant on energy from the seed of the plant,” she said.

“The seed is the battery. Leaves one and two help the plant to use the sun to recharge the battery.

“If we graze it at this stage, the plant won’t have enough battery energy to regrow leaves to potential capacity size.

“A shorter grazing rotation impacts this potential. And daughter tillering is dependent on the three-leaf stage.”

Applying fertiliser helps the plant to grow a bigger third leaf, which is the plant’s solar panel for recharging energy.

“The larger the leaf, the more energy is recharged into the plant — the bigger the leaf, the bigger the plant,” Bec said.

“Therefore, fertiliser impacts are greater on bigger plants.”

This is when the farmer needs to calculate the value of fertiliser against pasture growth in their farming system.

Bec recommended on/off grazing, commonly used in northern Victoria, to reduce overgrazing and help establish plants.

“Feeding silage and hay on the feedpad for cows to eat as they exit the dairy, or in the paddock, reduces the chance of them overgrazing pasture.”

She also recommends shortening the grazing rotation length or increasing rotations when the plant canopy gets dense.

“When you can’t see the ground, the sun can’t get to the plant’s battery, and the plant will start to die-off.

“Then the pasture has less nutritional value, and the cow is producing less milk in the vat.”

She cautioned keeping an eye on pastures to ensure daughter tillers grew at the base of the stem and did not grow up the stem.

“Daughter tillers growing too high up the plant don’t add volume to pasture.”