In his retirement, Phil continues to be a strong advocate for the important role that perennial grass species such as alfalfa can play in addressing environmental issues in agriculture. Currently, much of the information on the use of alfalfa originates in the eastern states. It is known as alfalfa in the Americas and Iberia and as alfalfa in the rest of the world.
Dryland salinity is one of the most debilitating environmental problems facing farms in the Wheat Belt. The effectiveness of the dry soil buffer also depends on annual rainfall and type of farming system. Growing alfalfa anywhere in the landscape can reduce groundwater recharge, regardless of the type of flow system.
Long-term APSIM simulations for various locations in the wheat belt have shown that well-managed alfalfa stands can produce an average of 4–7 tonnes of dry matter. Research in Western Australia has shown how alfalfa can support or improve year-round livestock production and reduce the impact of the summer-autumn feed gap, especially when weather conditions are favourable. The pronounced seasonality of rainfall in most of the wheat belt makes it rare to have green foliage all through the dry season.
These issues may warrant further research in systems with lucerne under the conditions of the Western Australian wheat belt.
![Table 2.1 Comparative leakage rates, and maximum dry soil buffer [lucerne systems (Luc.), annual systems (Ann.)] and soil water deficit before starting the third growing season after sowing lucerne for different locations in the Western Australian wheatbe](https://thumb-ap.123doks.com/thumbv2/5docco/10304909.0/19.892.96.803.723.1138/comparative-leakage-maximum-starting-different-locations-western-australian.webp)
Integrating lucerne into the farming system
Phased farming and grazing are the two agricultural systems used to integrate herbaceous perennial pastures into broad arable farming systems. The pasture can be established under a crop in the final year of the crop phase The pasture is. Intercropping' is a term widely used around the world to describe an agricultural system in which two or more different crops are grown simultaneously on the same land.169 'Pasture cropping' is a type of intercropping system that has been used for several decades in East- Australia is practiced. to produce a crop over native perennial grasses.6, 126 In the last decade the term.
Pasture production combines cereal crops and permanent pastures with complementary life cycles growing simultaneously on the same plot of land. For consistency, this document uses the current term 'pasture production' to reflect lessons learned from systems including cereal crops and alfalfa pastures. In pasture production, it is possible to produce grain without having to remove and re-establish permanent pasture.
Grass cultivation can also be seen as a modified phase farming system that makes it possible to insert a crop year into an otherwise long-term lucerne phase (Figure 3.3). Grazing crops can be managed opportunistically to suit seasons, market prospects and personal preferences, while keeping the water table low.138 In areas of higher rainfall, the impact of competition on production is expected to be low and waterlogging problems should be reduced. Any crop, including wheat, barley, oats, canola, lupine and field peas, can be used as a grass crop with alfalfa.
The increased grass cover crop can also help reduce soil erosion during the summer-autumn period if overgrazing is prevented. Grass growing can be more profitable than phase farming if plant competition is properly managed. Grassland cultivation may be more profitable than phased agriculture, but managing competition for water and other nutrients is the most important challenge to achieving potential benefits.13, 86 Some management strategies to reduce competition and keep water levels low are briefly discussed below.
The application of nitrogen to pasture crops has the potential to increase grain yield when the nitrogen is applied before tillage and moisture is not limited late in the growing season. A computer model adapted to Western Australian soils and climate was used to study this variation.38 Production and leakage were simulated under continuous cultivation and under four possible systems with alfalfa: continuous alfalfa, continuous phase farming, continuous grazing and tactical grazing. . Continuous phase farming alternates 3-yr wheat and 3-yr alfalfa and tactical grazing produces a grain crop in years with higher rainfall.
Management and economics of systems with lucerneof systems with lucerne
The farmer experience
Farm Characteristics ..58 Getting Started and Expanding ..59 Uses or Benefits of Alfalfa ..60 Disadvantages of Alfalfa ..63 Alfalfa Establishment and Management ..64 Progress with Alfalfa Adoption . It discusses why, how and where they fit alfalfa into the farming system and offers useful tips for its establishment and management. The final part uses information from various sources, including this survey and another from consultants, to briefly discuss the progress made in adopting systems with alfalfa.
The farms are located in the low to medium rainfall wheatbelt area from Buntina to Kojonup to Borden to Ravensthorpe. Cultivated areas show that farms are extensive in size with slightly smaller farms in the southern region (Table 5.1). The survey covered areas with low to medium rainfall, from 325 to 510 mm of annual rainfall.
Summer or non-growing season (Nov.–Apr. inclusive) precipitation averaged 30 percent of total precipitation, with more summer rain in the south relative to the other two regions. On average during the summer period, 50 per cent of the years at least one month with at least 50 mm of rain varying from one third of the years in the central wheat belt to two thirds in the south (Table 5.1). Farmers indicated that on average 19 percent of arable land was at risk of rising groundwater and salinity, with a range of 2 to 67 percent.
On average each year, 50 percent of the wheat belt's arable land is in crops and 50 percent in pasture. Cultivation and livestock are important industries for all farms in the study with cultivation and grazing occupying similar amounts of land on average, although in the lower rainfall Central region crops occupy. Fifteen of the 25 farmers interviewed indicated that both crops and livestock are of similar importance to their business with five listing crops as the main focus and five listing.
Almost all farmers used alfalfa to increase water use (Table 5.4), which reduced salinity spread and/or reduced depth. All farmers believed that after growing alfalfa, excess water problems stabilized or decreased. Twelve farmers and many farmers using piezometers based their understanding on observations (Table 5.2).
Most of the farmers used alfalfa to increase soil fertility, which can benefit pastures and crops after alfalfa is removed (Table 5.4). The increased soil fertility is due to improved nitrogen status in the soil due to nitrogen fixation with alfalfa. All the farmers said that the advantages outweighed the disadvantages and that the disadvantages could be managed.
The selection of the paddocks to grow alfalfa for excess water control was mainly based on soil observations and some data collection. This is a riskier way of establishing alfalfa due to the competitive effect of the crop and the variable climate. Most of the farmers used some herbicide on their alfalfa stands to control weeds, mainly grasses, and this is often applied late in the season to prevent seeding.
The average duration of the alfalfa phase was 4-6 years and of the sowing phase 3-4 years. The average duration of a salsify stand was 4-6 years, with some farmers leaving the stands under alfalfa for 12-13 years. Many farmers said that growing alfalfa is like growing canola and many of the establishment tips are similar.
Know the history of the paddock, for example if it has developed weed resistant weeds. There is an opportunity to increase the acreage of alfalfa in Western Australia if establishment and management practices are implemented to meet the production and persistence requirements of alfalfa in the wheat belt environment. Collaboration between leading farmers and researchers was critical to successfully developing an understanding of alfalfa's role in agriculture.
59 Fedorenko D, Loo C, Renshaw D (2005b) Alfalfa incorporation into farming systems in the dry central wheat belt of Western Australia. 77 George R, Clarke J, English P (2008) Modern and palaeogeographic trends in the salinization of the Western Australian wheat belt: a review.
