A course that covers the design, installation, maintenance, operation and evaluation of simple irrigation systems. This course focuses on irrigation systems for row crops (eg. vegetables & cut flowers) and orchards.
“Whilst sharing similarities with other irrigation courses, this highly functional and practical course also has a specific focus on the irrigation of crops. It will be of interest to anyone who grows, or who wishes to grow, crops whether on a large or small scale. All aspects of irrigation from system types and design to pumps and filters are discussed, in light of soil characteristics, drainage, and plant requirements.” - Gavin Cole B.Sc., Psych.Cert., Cert.Garden Design, MACA, ACS Tutor.
There are 10 lessons in this course:
Soil Characteristics And Problems
Estimating Plant And Soil Requirements
Drainage - drainage systems, dams, etc.
Types Of Irrigation Systems
Hydraulics - discharge and flow rates, etc
Pumps And Filters
Selecting The Right System For The Plant
Design And Operation Of Systems
Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.
Identify and consult appropriate sources of information for the irrigation industry.
Explain the significance of soil characteristics to irrigation.
Determine when to irrigate in a small scale situation.
Explain the drainage aspect of handling water.
Explain the operation and selection of irrigation systems.
Explain the operation and selection of trickle irrigation systems.
Determine specifications for the design of an irrigation system.
Explain the pumps and filters needed for handling water adequately for crops.
Supervise the installation of an irrigation system.
Design and operate an irrigation system for crops.
Choosing an Irrigation System to Suit the Crop
There are many different reasons why we select one irrigation system over another. The money available to set up a system is an obvious consideration, particularly for home gardens, but the cost effectiveness and ease of operation are also of major concern, particularly in commercial situations, or in a parks department where labour costs can be high.
Has been used in orchards in the past extensively. This method wastes water, but once set up is inexpensive to operate, outside of the cost of water (i.e. low equipment and labour costs).
Flood does not get the foliage of the plant wet.
Flood is thorough, wetting all parts of the ground.
Overhead sprinklers can be used to protect plants from frost, as well as irrigate. Foliage can stop even distribution of water to some parts of the ground.
Wet fruit can be more susceptible to disease.
Sprinklers are expensive to install and need high pressure (often a pump) to operate.
Operates on low pressure, directs water to exactly where it is required, overall uses less water than sprinklers or flood. Does not wet fruit. Trickle is more effective at disposing (leaching) dangerous salts from the soil.
Your choice of irrigation system will depend on:
- Water availability (quantity and quality)
- Water pressure
- Labour available
- Money available to invest in a system
- Soil type
- Whether disease susceptibility is higher if foliage or fruit are wet
- Whether there is a need for frost control
Different Crops have different needs
Every type of crop will have it's own peculiarities with regards to irrigation needs. Adequate and appropriate irrigation for one type of plant may be too little, too much, or inappropriate for another.
Grapes for instance can be adversely affected by too much moisture on fruits, particularly when close to harvest. This can increase the chance of disease, and in turn reduce both the quality and quantity of the crop. For this reason, most parts of the world where vines are grown commercially have a relatively low rainfall (usually less than 700mm annual rainfall).
If an area has very low rainfall in autumn (eg. in parts of Germany), but higher rainfall in summer, vines can be grown quite successfully without irrigation. Drier climates however will need supplementary irrigation to ensure a good commercially viable harvest.
Water management is particularly critical with vines. Too much water can cause just as many problems as too little:
- Overhead irrigation makes the fruit and foliage wet, and that promotes disease.
- Rain or overhead watering is more of a problem in hot weather.
- Flood, drip and other forms of irrigation while not directly wetting the foliage, can increase humidity and may in turn increase disease.
- Overwet soils starve the vine roots of oxygen, causing an overall deterioration in plant health.
- Too much water causes more leaf growth, which can shade fruit bunches and reduce both the number of bunches and the quality of wine which can be produced.
- Water stress (ie. lack of water) must be avoided prior to veraison (Explanation: After flowering, fruit develops in three stages.
- The first stage involves a burst of fast growth, the second stage is a slow period of growth, and the third stage is a final fast burst of growth. The final stage is called "veraison").
- Heavy watering to bring the soil to field capacity prior to veraison will usually provide enough water to see the plants through to harvest.
- Irrigation in very dry climates, or in drought years should usually only be done before veraison.
- Vines can tolerate high rainfall and excess water in winter while dormant as long as they don't remain waterlogged for an extended period.
- Water Stress on grapes is indicated by reduced growth, extra short internodes (ie. spaces between the buds on stems or shoots), reduced berry set (ie. young berries drop off), yellowing or dropping of leaves and uneven or imperfect ripening of berries.
WHY DO THIS COURSE?
When you enrol in a course with ACS Distance education you will have the experience and knowledge of industry experts at your finger tips.
This course will help you to gain the fundamentals needed to apply irrigation efficiently and effectively.
If you are working in crop farming, looking to work in it or want to start off a an irrigation advisor then this course will help you towards your goals.