Stamina® GT5 is a breakthrough in the development of grazing tolerant lucernes for the Australian environment. It is a true grazing tolerant lucerne which has been trialled over many years under the internationally recognised Standard Test Protocol for grazing tolerant lucernes (see page 6 for more information). It has low, broad crowns and is naturally of high forage quality with fine stems and high leaf-to-stem ratio. Stamina® GT5 lucerne is the ultimate choice where a stand is required for prolonged periods of set-stocking.
Developing grazing tolerant lucernes for Australia’s dryland farms has taken nearly two decades and was a a joint venture project between PGG Wrightson Seeds Australia and CalWest Seeds in the USA. The products were initially developed in the US after a 6 year screening programme in which elite breeding lines and successful commercial varieties were set stocked by both sheep and beef cattle for a period of 6-7 months per year. Paddocks were maintained at a constant vegetative height of 2-5cm throughout the grazing periods.
Further screening was conducted in Australia by PGG Wrightson Seeds who evaluated 24 advanced lines in trials that ran for 7 years. Plots were grazed for periods of 10 months at a stocking rate of 40 sheep/ha.
Lucerne varieties bearing the Stamina® designation were selected as ‘best of the best’ in these ultra-rigorous evaluations. Australian farmers are encouraged to ask other seed companies that claim their lucerne varieties are grazing tolerant were they developed. Farmers are advised to plant the best, proven grazing tolerant (GT) varieties from PGG Wrightson Seeds.
Stamina® GT5 like all other lucerne is small seeded, so therefore it is important to ensure that the sowing of Stamina® GT5 is done correctly to ensure the best results for establishment. There are some key fundamentals when sowing lucerne including seedbed preparation, weed control, sowing depth and sowing technique. Following these key steps will help achieve a good establishment of lucerne.
Seedbed preparation – preparing the seed bed takes into consideration the soil type and cultivation of the soil to ensure the soil is fine. This will aid the soil to seed contact at the time of sowing as well as good supporting moisture infiltration around the seed either after a rainfall event or irrigation.
Poor weed control is one of the most common issues that can lead to poor lucerne establishment.
Weed control must start the year prior to sowing the lucerne to ensure adequate time and opportunity to control any weeds that are present in the paddock. This should also reduce the need for post emergent herbicides to be used in the young lucerne crop as this can retard growth.
The sowing depth needs to be managed as lucerne is a small seed and therefore only needs to be sown at
no more the 15mm deep. This will enable the lucerne to germinate and the seedling to rise above the soil to begin photosynthesis.
The sowing technique is the method of actually getting the seed into the soil. With so many different options for sowing equipment, it is important to understand the impact this can have when sowing lucerne. Accuracy of sowing rate, equipment condition (shears, knife points or discs) and final compaction (press wheels, harrows or tyre roller) are all important when looking to successfully establish lucerne.
While Stamina® GT5 has gone through a tough protocol for testing for grazing tolerance, it is not recommended that it is treated in this way in a commercial situation. However, what the testing does do is give the
farmer confidence that Stamina® GT5 will survive better than most other lucernes if treated in less than ideal management for lucerne persistence.
As lucerne relies on stored energy (carbohydrates) in its root system to produce new foliage following grazing, it is recommended that Stamina® GT5 be managed in a rotational grazing system. The recommended rotation period is between 30-35 days rest from grazing during the growing period (rotation lengths may need to be extended during the cooler months due to slower growth). When grazing lucerne, it is ideal to graze the plant down to 5cm in height and then have the stock taken out. This type of management will ensure a strong lucerne stand for many years which will make Stamina® GT5 a very sound investment.
Minimum 350mm rainfall per annum unless irrigated