Article Summary:

Well, something caused the summer to fall, good for us that autumn is here now. Now is a great time to set up autumn grazing management. Autumn requires careful planning and preparation for upcoming winters. Wisdom is to make the most out of the autumn break. Learn with us a way to determine grazing rotation days by using leaf growth rate, and area offered per day.

The times of scorching heat is over, and temperatures are falling. It is time for the farm management to set into motion an autumn grazing plan.

Over the summer, in regions with limited rainfall, there is an increased grazing pressure on irrigated areas of farms which results in less pasture cover. Also, there are autumn breaks to consider too when setting up an autumn grazing plan.

To get the most out of Autumn break, a comprehensive grazing plan along with nitrogen application and renovation is necessary. Grazing management is a critical factor in soil, water, and nutrients management. Poor grazing management may lead to the degradation of natural resources and cause severe financial loss to the farm.

Today we delve into grazing management in autumn. We will calculate how to set up grazing rotation based on the leaf growth stage and how much area to offer per day for optimum grazing. We will also discuss how long grazing duration ought to be along with post-grazing targets. Without further ado, let's take the plunge into grazing management this autumn.

Aims of Grazing Management

Grazing management aims to maximise pasture productivity, consumption, and high-quality feed. Utilizing pasture to its full potential is key to optimising profits. Farm management can achieve that by setting grazing rotation based on leaf stage, grazing duration, and meeting the post-grazing targets. Let’s discuss them one by one.

Set up grazing rotation based on leaf stage

The leaf stage is of prime importance when setting up a rotational grazing system. For pastures based on ryegrass, grazing at a 2 to 3 leaf stage will maximize the amount of pasture grown. The monitoring of the leaf stage indicates when the paddock is ready to graze. The optimal time is between 2 to 3 leaf stages.

If leaf stage-based grazing rotation was maintained despite dry summer and less pasture growth, this ought to be maintained. On the other hand, if paddocks that relied on rainfall were not grazed during the dry periods, there will be a bulk of pasture at a similar leaf stage waiting to be consumed. In both scenarios, there is a need to establish the right rotation system and acquire a feed wedge.

When every paddock is at a different stage of regrowth, it is called a feed wedge. Farmers across Australia start an early autumn grazing to achieve the feed wedge.

Even if there is a bulk of paddocks close to 3 leaf stage, the rotational grazing should still be set up to achieve the feed wedge. Some paddocks may be past the 3-leaf stage by the time their grazing turn arrives, which means some wasted pasture. If they are grazed quickly after the autumn break, there will continue to be paddocks at the same leaf stage.

Determine grazing rotation in Autumn

Estimation of leaf emergence rate is needed to determine the grazing rotation. The rate of leaf emergence depends on temperature and moisture. In presence of optimal moisture levels after the autumn break, the temperature will determine the rate of leaf growth. Warmer the temperature, the faster the leaf emergence rate. Under given conditions, the leaf emergence rate will be around 10-15 days/leaf in early autumn.

Leaf stage Rotation days
1-leaf 10-15 days
2-leaf 20-30 days
3-leaf 30-45 days

In autumn, soil temperature will be decreasing slowly. It is better to allow the pasture cover to grow and thus set up a longer rotation.

Determine the area offered/day

Use the examples below to calculate the area offered per day.

Leaf stage Leaf growth rate Grazing rotation Area offered/day
2-leaf 13 (13*2) = 26 (100/26) = 3.8 ha/day
3-leaf 13 (13*3) = 39 (100/39) = 2.5 ha/day

If the pasture in the area is not enough to fulfil the demand, consider decreasing the number of cows or using other means to increase the supply.

Monitor leaf growth rate and match the grazing rotation accordingly. As temperature drops, leaf growth slows down and there is a need to match the grazing rotation with it.

Grazing duration in Autumn

Grazing duration should not be longer than two to three days. If cows continue grazing one pasture longer than 3 days, they would eat regrowing pasture thus slowing down the growth rate and reducing pasture yield.

One way to avoid overgrazing is using back fencing.

Reach post-grazing targets

Ensure that post-grazing height is 4-6 cm. This is equivalent to 1400-1600 kg DM/ha. This step ensures the quality of feed for future grazings.

This brings us to the end of the article. Until we meet again, Happy Grazing!

- The Dedicated Team of, 2022-03-25