Trees For Rehabilitation (Reafforestation)

Course CodeBHT205
Fee CodeS2
Duration (approx)100 hours
QualificationStatement of Attainment

Would you like to work in a field that helps the environment?  Environmental rehabilitation of degraded landscapes and contaminated sites is an important and growing field - this course covers the fundamentals required to start or advance your career.

Student Comment: 'I definitely learned a lot from [the course) but it was also beneficial in affirming [and raising my confidence] in what I already knew.' Katrina Merrifield, Masters Conservation Science, NZ, Trees for Rehabilitation course.

The significance of caring for the environment has been receiving more and more attention in recent times as we come to understand the importance of limited resources and the effects of human activities on the environment. The desertification, erosion and general degradation of once fertile lands is prompting us to investigate why and how these processes have occurred. It has also lead to research into how we can reverse and stop further damage to our environment.

Natural forests are amongst the most stable and productive ecosystems. We need to plant and conserve forests for their conservation value, to help maintain healthy air, soil and water and for their potential to provide food, forage, fuel, timber and even medicines.

This course is designed for people working or wanting to work with environmental rehabilitation and contaminated sites recovery. It develops an understanding of environmental systems and the rehabilitation of degraded landscapes. You will learn about seed collection, storage and germination, propagation, plant selection, establishment techniques, and controlling pest and disease after planting.

Lesson Structure

There are 10 lessons in this course:

  1. Approaches To Land Rehabilitation
  2. Ecology Of Soils And Plant Health
  3. Introduction To Seed Propagation Techniques
  4. Propagation And Nursery Stock.
  5. Dealing With Chemical Problems
  6. Physical Plant Effects On Degraded Sites
  7. Plant Establishment Programs
  8. Hostile Environments
  9. Plant Establishment Care
  10. Rehabilitating Degraded Sites

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.

Aims

  • Compare different approaches to land rehabilitation, to determine strengths and weaknesses of alternative options on a site to be rehabilitated.
  • Determine techniques to maximise plant development in land rehabilitation situations.
  • Explain the different ways of producing seedling trees for land rehabilitation purposes.
  • Determine appropriate plant establishment programs.
  • Develop procedures to care for plants, during establishment in an hostile environment.
  • Manage the rehabilitation of degraded soil.
  • Explain the effect of plants on improving a degraded site, both physically and chemically.

What You Will Do

  • Determine ten different examples of land degradation on sites visited by you.
  • Explain different reasons for land requiring rehabilitation, including:
    • Salination
    • Erosion
    • Mining
    • Grazing
    • Vegetation harvesting
    • Pests
    • Reduction of biodiversity
    • Soil contamination
    • Urbanisation.
  • Compare the effectiveness of different policy approaches to land rehabilitation by different agencies and organisation, including:
    • Different levels of government
    • Mining companies
    • Developers
    • Conservation groups (i.e. tree planting bodies, landcare groups).
  • Develop a risk analysis for a specified site to be rehabilitated, by determining a variety of plant health problems which may impact on the success of plant establishment.
  • Analyse the failure of plants to grow successfully on a visited land rehabilitation site.
  • Develop a procedure to enhance the success rate of land rehabilitation plantings on a degraded site visited by you.
  • Describe the use of mulches, to maximise plant condition in a specified land rehabilitation tree planting project.
  • Explain different processes of establishing seedlings on land rehabilitation sites, including:
    • tubestock nursery production
    • direct seeding
    • pre-germinated bare rooted seedlings.
  • Determine factors which affect the viability of establishing five different species of plant seedlings, from five different plant families; on a specific degraded site.
  • Compare the benefits of acquiring plants for a project by buying tubestock, with propagating and growing on, or close to, the planting site, with reference to:
    • costs
    • plant quality
    • local suitability
    • management.
  • Prepare production schedules for a plant species, using different propagation techniques, summarising all important tasks from collection of seed to planting out of the tubestock.
  • Calculate the cost of production for a tubestock plant, according to the production schedule developed by you.
  • Estimate the differences in per plant establishment costs, for tubestock, compared with direct seeding methods, for planting on a degraded site.
  • Describe three different methods of planting trees for rehabilitation purposes.
  • Describe different plant establishment techniques, including:
    • wind protection
    • frost protection
    • pest control
    • water management
    • weed management.
  • Describe an appropriate method for preparing soil for planting, at a proposed land rehabilitation site in your locality.
  • Evaluate plant establishment techniques used by two different land rehabilitation programs inspected by you at least twelve months after planting was carried out.
  • Determine the needs of plants after planting, on two different proposed land rehabilitation sites.
  • Describe two different, efficient ways, of catering to the needs of large numbers of plants after planting.
  • Collect pressed specimens or photographs of twenty trees for a herbarium of suitable trees for rehabilitation, and including information on the culture and care of each tree.
  • Describe different types of soil degradation, detected in your locality.
  • Determine the risk factors involved in soil degradation, relevant to your locality.
  • Compare two different alternative methods of treating each of three different soil degradation problems identified and inspected by you.
  • Develop an assessment form to use for evaluating the sensitivity of a site to land degradation.
  • Evaluate a site showing signs of degradation, selected by you, using the assessment form you developed.
  • Plan a rehabilitation program for the degraded site you evaluated, including
    • a two year schedule of work to be completed
    • list of quantity and type of materials required
    • approximate cost estimates.
  • Explain the effect six different plant species may have resisting soil degradation.
  • Explain how different plants can have different impacts upon the chemistry of their environment, including both air and soil.
  • Evaluate the significance of a group of plants, to the nature of the microclimate in which you find them growing.
  • Compare the appropriateness of twenty different plant species for different degraded sites.
  • Determine five plant varieties, suited to each of six different degradation situations.

Trees form the foundation and framework of a landscape.
 
More than any other plants, they determine the characteristics of the environment. Their roots hold the soil together, and their leaves shade the ground surface. Without trees, the air would be hotter on a hot day, and colder on a cold day. Animals are sheltered by trees, soil is enriched by their rotting leaves, oxygen levels in the air are raised, and pollutants are filtered out of the air.
 
Before selecting the trees for any location,  you should how shaded, protected and enclosed you want your site to be. The balance of sun and shade is all-important. In our generally hot summers, shade is most desirable for some places, but you may well want to have sunny areas for others.
 
You may decide to plant lots of trees to create a forest-like environment, concentrating on shade-loving shrubs and ground covers beneath them; but if you want a blanket of flowering, sun loving plants on the ground; too much tree cover may inhibit that possibility.
 
Choose the Right Tree
Whenever you are selecting trees to plant,  always consider the following:
 
Eventual Height
Majestic forest trees are for larger country gardens and parks. They can be overwhelming in a smaller suburban landscape, casting too much shade and possibly creating problems with their roots. Should they drop branches or break in the wind they can cause major damage.
 
Spread of Canopy
Tall narrow trees create less shade than spreading canopies. Larger trees drop more leaves. When trees are seeking light they may grow more upright and not spread as much; but in an open area, trees can sometimes (eventually) develop a canopy that is wider than might be expected.
 
Density of Canopy
Dense foliage means more shade. Deciduous trees can have a dense canopy in summer; but over winter, create very little shade at all. Eucalypts (most of them anyway) tend to have rather light canopies and cast filtered shade; Rhododendrons can produce a much denser canopy. Every tree is different..
 
Roots
Some trees are more inclined to have damaging roots which lift paths, crack foundations or block pipes. Some of the worst culprits are tall willows, Eucalypts in small gardens, Ficus trees blocking drainage pipes, etc.
 
Number of Trees
Do you already have trees growing in your garden? Remember that extra trees will increase shade in the garden. The average suburban home should only have three or four large trees (i.e. over 10m tall) and they should be kept away from buildings, pipes and pavement.
 
Growth Rate and Lifespan
Some trees grow very fast, e.g. most acacias and eucalypts, but may have only 20 years of life (especially acacias). Others may be slower growing but will live for a century or more. It is a matter of balancing the desire for quick effect against long term benefit. For instance, you might plant fast but short-lived trees as “nurse trees”, planning to remove them in 10 or 15 years when the slower ones are coming to maturity. This course of action is really only an option if you intend remaining in your current home long enough to see the fruits of your labours.
 
Foliage
Try to get a variety of colours, shapes and textures in the foliage of the trees you use.
 
Flowers
Tall trees with attractive flowers are not always a good idea. Once the tree is fully established, the flowers may be so far above the ground that you might never notice them.
 
Bark
Often the most visible part of a tree is its bark. As such, trees are often better selected for their attractive bark than for the flowers or foliage.
 
Fruits or Berries
These can be long lasting and attractive, or they may be edible. Trees with berries will often attract birds and bats into the garden. One problem with fruit or berry trees is fruit falling onto paths and driveways and making them messy. If you want low maintenance, position a large trees or ones with invasive roots carefully. Some trees drop seeds that germinate readily; which can create a weed problem; others may drop seed; but without a high rate of germination occurring.

 

WHERE WILL THIS COURSE TAKE YOU?

  • Into environmental restoration
  • To the rehabilitation of land systems
  • Work as a tree assessor
  • Towards environmental assessment
  • Post planting management

 

More from ACS