PASTURE MANAGEMENT

Lesson Structure

There are 8 lessons in this course:

1. Introduction to Pastures
2. The Grass Plant
3. Pasture Varieties
4. Site Considerations
5. Establishing New Pastures
6. Managing Existing Pastures
7. Managing Stock on Pasture
8. Pasture Management Work Tasks

How to Establish the Chosen Plant Cultivars in a Pasture

There are four main ways of preparing land for pasture sowing:

1.  Prepared seedbed
   
2.  Reduced Cultivation
   
3.  Direct Drilling
   
4.  Surface sowing

One of the most important aspects in successful pasture establishment is seed to soil contact. Pasture establishes best when seeds are sown at a shallow depth and covered with soil. This contact is required to allow moisture for seed germination. Prepared seedbeds provide the best option but are not always feasible.

Using a Prepared Seedbed

Grass seeds like a firm, level, weed-free seedbed.
There are three stages in preparing a ploughed seedbed:

1.  Primary tillage: the initial breaking of  the ground that buries much of the surface material
   
2.  Secondary tillage: further breaks down the soil and kills weeds
   
3.  Sowing

Machinery used in seed bed preparation includes:

•  Sub-soilers and rippers: designed to shatter and penetrate the hard surface/subsurface layers
• Chisel  ploughs
• Disc ploughs
• Offset disc ploughs
• Mouldboard ploughs
• Scarifiers
• Cultivators
• Seed Drills
  Harrows

The land is first deeply tilled (preferably with a tyned implement) to allow the soil to absorb as much rainfall as possible. It is then lightly tilled to conserve moisture but to remove young weeds. Rolling may be necessary before and after sowing the seed. The final land surface should be made level in case the crop is harvested for hay from time to time. The plant furrow should be shallow. If it is deep, the rut quickly becomes filled with wind-blown soil that buries the grass seed too deeply for germination.

The soil should be analysed before sowing so that the fertility can be brought up to the required level if necessary. Grasses require 15 ppm phosphate while legumes need 30 ppm. Phosphates should be added to the soil just before sowing. The addition of legumes into the pasture mix will reduce the need for nitrogen in future years. To establish the pasture, however, it is important to fertilise as recommended by the soil analysis. Many grass species are relatively resistant to soil acidity with the exception of some legumes (e.g. Lucerne and sainfoin).

Sowing the Seed

The soil should be as moist as possible before sowing the seed. Summer pastures should be established at a time that will coincide with reliable rainfall in the area. Early sowings of these pastures must be avoided because the soil temperature may be too low for fast germination. Late sowing may result in poor germination because of large swings in temperature. Winter pastures should be established in autumn to take advantage of the swings in temperature. Rye-grass, for example, needs cold to germinate. However, the daytime temperatures should not be to low. The aim is to establish a strong plant before the cold of winter sets in.

Another Method- Direct Drilling

Direct drilling is a good alternative to preparing a ploughed seedbed. The advantages of this method include:

• Less soil damage: The risk of erosion, “pugging” of the soil by animals, crusting, and other structural problems is greatly reduced. 
• Faster: You can access the paddock more readily than a ploughed paddock and there are fewer operations to perform.
• Better seed placement: Putting the seed at exactly the right depth for moisture uptake. The seedlings are anchored well and can be grazed at an earlier stage when compared with broadcasting and aerial sowing.
• Desirable species are retained: By choosing the correct herbicide, desirable pasture species are retained.
• Flexibility: The pasture can be still grazed until the herbicide is used.
• Fewer weed problems: Ploughing creates the right conditions for weed seeds to germinate.
• Less cost: Less machinery is used.