Farming without a label
Authors: Fiona Baker and Jane Court, Agriculture Victoria
Every now and then a ‘new’ farming system comes along claiming to do better things for the land, people and animals. While it can be very helpful to have a process to follow or to hook up with a group of like-minded people, it is the core principles of good farming practice that are important and most have been around and used for some time. This article outlines some of the practices that support healthy soils, land, pasture and livestock while taking into account farming for profitability and individual goals.
Some form of rotational grazing that allows the desired plants to capture light, recover and build root reserves will help to optimize growth rates and persistence. The long-term grazing trial at Broadford, conducted by Agriculture Victoria from 1994–2003, demonstrated the benefits of rotational grazing and appropriate fertiliser use on profitability and sustainability. Correcting soil phosphorus deficiencies had a bigger impact on improving pasture growth than changing grazing method. However, rotationally grazing the pasture instead of continuous grazing allowed higher stock carrying capacity, while simultaneously improving persistence of phalaris. Other benefits included fewer broadleaf weeds, more groundcover over summer and autumn, less drought feeding costs, drier soil profiles, reduction of sheep camps, and lower maintenance rates of phosphorus fertiliser.
Use grazing techniques that suit your environment and system as not always does one way suit all. It is about giving plants adequate rest periods so they can maximise their leaf growth and root recovery and maintain good groundcover. Rest periods from grazing should not be too short or too long for the speed of growth of the plants in your system, as both impact on the resilience of the pasture. Using leaf appearance rates to help set the rotations will also help to balance stock needs and pasture availability to ensure paddocks are not overgrazed.
Tillering is one of the main methods of reproduction for a perennial grass. To ensure good tillering, resulting in good plant density and groundcover, light needs to get to the base of the plant regularly. If the pasture is left for too long during the growing season and light can’t get to the base, plants may still tiller, but they do what is called aerial tillering. Instead of the tiller growing from the base of the plant and eventually forming its own root system, the tiller will form part of the way up the parent plant stem.
Graze at the appropriate leaf stage
The leaf stage relates to the plants physiological readiness to be grazed. Grazing at the appropriate leaf stage allows growth of new leaves, allows new root growth, replenishment of the root and stem reserves and provides the plant enough energy to initiate and support additional tillers. The appropriate leaf stage for grazing some common grasses is:
- Ryegrass and fescues: 3–4 leaf stage
- Cocksfoot and Prairie grass: 4–5 leaf stage
- Phalaris: 4 leaf stage
Rest periods need to change throughout the seasons and can be based on the leaf emergence rates. If you allow additional leaves to grow past the recommended leaf stage, you can get an accumulation of dead material, which decreases the quality of the feed for stock. Animal performance does not increase linearly as the pasture gets taller. Accumulation of dead material can also cause shading to the base of the plants resulting in a reduction of tillering.
Note that managing native grasses may require specific management. Some key management points from a native grass trial in East Gippsland showed:
- Rotationally graze native pastures to a minimum herbage mass (1200 kgDM/ha).
- Fertiliser application can increase the legume component and nutritive value of the pasture without reducing the native grasses.
- In spring, apply extra grazing pressure to ensure that clover does not smother native grasses.
- In summer, avoid long rest periods during the growing season because they result in standing dead material, but reduce grazing pressure in summer, allowing native seed set.
- In late summer, retain plant litter to minimise bare ground. (See also: Improving high country native pastures, SheepNotes Spring 2020)
Targets for maintaining adequate groundcover for soil protection and moisture retention have also been around for a while. Targets are suggested as 70 per cent groundcover but aim for 100 per cent in steeper paddocks. Having too much cover in the autumn will restrict germination of sub clovers which provide nitrogen for the grasses and also higher feed quality for stock. Reducing stocking rates to achieve targets does not have to mean selling stock. Stock containment areas are a useful tool to feed animals intensively and are used by some farmers annually to optimise growth at the autumn break (See also: Farmer Tips on Autumn Saving, SheepNotes Autumn 2021). How and what to destock is based on economics, personal choice and attitude to risk, feeding and infrastructure, etc.
Each time product (meat, wool, hay, etc.) is sold or moved from the farm, nutrients are removed. These need to be replaced to avoid mining the soil and reducing the health and vigour of the plants and soil environment. Much of the soil organic carbon comes from the growth and death of plant roots. It also happens via the transfer of carbon enriched compounds from the plant roots to soil microbes. Without adequate soil nutrient levels, good strong plant growth struggles to be supported, the soil biota which rely on the soil organic carbon as a feed source from the plant. Note that in the Broadford grazing trial, although rotational grazing reduced fertiliser requirements through better nutrient spread, it did not eliminate the need for adding nutrients.
Options to improve pastures by resowing
Grazing and nutrients will help to improve and maintain good pastures but there are situations when resowing a pasture may be a better option (See also: Getting the most out of old perennial pastures, SheepNotes Spring 2018) due to a high prevalence of poor grass or weed species (e.g., bent grass). Productive plant species that grow well due to grazing and nutrients contribute to better animal performance with less methane emissions and soil carbon.
Managing in good years
Good seasons can be a challenge to manage all the surplus dry feed, which loses quality over summer and can limit clover germination in autumn. Cutting hay or silage can be an opportunistic strategy for storing fodder for future years, to help get regrowth if follow-up rains occur and for weed control. Other options include grazing paddocks that will drop in quality first. The Grasslands Productivity Program and Long Term Phosphate trial at Hamilton, showed the quality of dry feed was higher for longer in the well fertilized and grazed pastures. These ones will maintain stock later in the season and so may be grazed later.
Maintaining good groundcover, pasture persistence, grazing management and healthy soils are all achievable and part of good common farming practices. It is a matter of picking and using the best bits of any strategy that suits your situation with some evidence-based science behind it.
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