A dilemma facing many small farmers is whether or not to renew pastures and if the costs associated with this are worthwhile. The short answer is, yes it is costly to renew a pasture, however the benefits are present in regard to increases in production and potential livestock health. Renewing pastures and increasing stocking rates is a good way for small area farmers to increase farm income. Pasture renewal can result in higher levels of production and income being achieved off the same land area. In most situations this is more cost effective than buying extra land. The benefits that come from newly sown pastures can only be realised where stocking rates are increased and extra pasture grown is eaten.
To renew or not?
Before deciding to renew a pasture, firstly decide if the existing pasture needs replacing. This decision needs to be based around the goals of the livestock enterprise and overall farm. If your aim is to run a few breeding cows and make some money on the side, then the drive to improve pastures and increase production will be less compared to someone who wants to trade cattle and try to maximise income off their small land area. There are a number of less costly management activities that can be undertaken to improve existing pastures without removing them completely. These will be discussed later in the article.
The best way to know if a pasture is old and run-out is by looking at your livestock. Your livestock are a true reflection of the pasture they are eating. Successful livestock production is often described as fifty percent genetics and fifty percent nutrition. If your pasture lacks adequate growth, have low beneficial (clover) plant numbers, a high weed population or is generally performing below expectations it is common for your livestock to show similar signs of tiredness, hollowness and poor production. These symptoms are an important sign that it is time to renew your pasture. The best place to start on your farm is where you are going to get the best ‘bang for your buck’. This can be determined by choosing the paddock with the most potential, one with the best aspect (easterly), heavy soil type or high soil fertility levels.
Pasture establishment methods
The most successful way to establish a new pasture is by removing the old one. This can be done through a variety of methods including cultivation, slashing, burning or spraying. New pastures are successfully established where weeds and other competing plants have been killed, where moisture has been stored and fertiliser applied prior to or at planting. Any number of methods can be used to sow a new pasture including over sowing, broadcasting, sod-seeding and direct drilling. Regardless of the sowing technique used, the most crucial step in the pasture renewal process is to plan well ahead and ensure that the paddock has adequate preparation.
Enhancing pastures without the large renewal cost
If the cost and time required to establish a new pasture is not what you want, then there are a number of other management activities that can be undertaken to improve the pastures that are already present. These include:
- Fertiliser application. Often poor producing pastures are a result of a lack of soil nutrients. Undertaking a soil test and applying fertiliser is often the best first step in increasing the pasture production.
- Spraying of weeds. Pastures that contain high levels of weeds are often unproductive, weeds compete for space, water and sunlight. A good method to increase production is by spraying out weeds using a selective herbicide (one that only targets the weeds) leaving the pasture behind.
- Broadcasting of legume seeds. Broadcasting legume (sub, white clover) seed is a cost effective way of increasing the quality of the pasture. This activity can be coincided with fertiliser spreading to reduce the cost.
- Slashing of dead material. Dead plant material is not easily digested by livestock. Pastures with high levels of dead material result in poor livestock production. Slashing is an ideal way of removing this dead material. This activity also allows increased levels of sunlight to reach beneficial legume pasture species.
Preparation is key
Preparing to plant a new pasture should start a minimum 2 years before it is to be sown. The preparation phase allows time to remove weeds (both growing and seeds in the soil), improve soil fertility levels and correct any soil structure and pH issues. Sowing a new pasture is costly, with the average pasture renewal costs ranging from $200-$800/ha. Therefore, the preparation period is vital in reducing the risk of establishment failure and costly mistakes. The cost of pasture seed is approximately 25% of the total pasture renewal cost, depending on the pasture varieties to be sown. Fertiliser makes up the largest expense, with 50% of the total pasture renewal cost. Purchasing pasture seed should be seen as an investment. Always use good quality seed, ask for certified seed as this ensures it has met minimum purity and germination standards before it can be sold.
Below is an example of a checklist and timeline involved in a pasture renewal program. In this example herbicides are used to kill weeds and direct drilling is used to establish the pasture.
- (Sep-Dec, 2010) Spray out existing pasture to ensure annual weeds do not set seed. This can be done using a knockdown herbicide like Roundup. The period between spraying and planting is known as the fallow period where plant competition is reduced and soil moisture is conserved for planting.
- (Jan-Mar, 2011) Soil test, apply lime, gypsum and fertiliser if required. Click here for our on farm soil testing service. Spray out weeds using a knockdown (kills all growing plants) herbicide, as close to sowing as possible.
- (Mar-May, 2011) Direct drill an annual crop e.g. oats or ryegrass. Apply starter fertiliser (Nitrogen, Phosphorus, Sulphur) at sowing.
- (May-July, 2011) Monitor crop for insects such as earth mite and spray out unwanted broadleaf weed species with a selective herbicide.
- (June-Dec, 2011) Graze crop until it has finished growing. The paddock may require another weed spray in spring/summer if there are high levels of weeds still present.
- (Feb-May, 2012) Spray paddock out as close to sowing as possible. Direct drill pasture seed with starter fertiliser.
Regardless of the establishment technique used (direct drilling, broadcasting, sod seeding), the best results will come from an even seed bed. Most pasture seeds are small in size and are therefore sensitive to sowing depth. Ideally seeds should be sown 10-20mm under the soil surface. Seed to soil contact should be enhanced with the use of a roller, harrow or press wheel. Post sowing (2-8 weeks) pastures should be monitored for weed and insect attack. Newly sown pastures that have un-controlled weeds or severe insect attack, often have a reduced lifespan and poor levels of productivity. During establishment weeds and insects need to be correctly identified and spray thresholds (how many are present and at what level to spray) established before control measures are undertaken. Once successfully established pastures should be managed using rotational grazing, controlling weeds with herbicides and replacing soil nutrients with fertiliser.
Renewing a pasture should follow a methodical and well planned process. Those who wake up today and decide to sow tomorrow are often bitterly disappointed. Small area farmers can enjoy production and income benefits similar to their larger counterparts from pasture development. The success of pasture development and the ability to increase profit levels depends of the ability of the farm owner/manager to eat extra pasture that is grown. This may involve a number of strategies including agistment, the purchase of extra livestock or cutting and sale of hay or silage.
Where to from here?
For further information on pasture development, purchase a copy of Pastures.
- Over-sowing: Sowing seed into existing pasture using narrow tines or discs, reducing soil disturbance.
- Direct drilling: Sowing seed into a seed bed which has not been cultivated, after the application of herbicide.
- Sod-Seeding: Sowing seed into an existing pasture once it has been slashed or mulched. Seed is broadcast or scratched into the soil surface.
- Seed to soil contact: The level of contact that the seed has with the soil. The higher the levels of seed to soil contact the better the pasture establishment.
- Purity: Percentage of the seed sample which is pure seed, showing weed seeds and other components.
- Germination: Amount of seed which germinates after 14 days, represented as a percentage.
- Agistment: Grazing livestock on another farm, other than your own for an agreed price, usually per head, per week.