Add to What You have Already Learnt
This course is designed to build on a your previous knowledge or experience with tree management.
- Follows on from Arboriculture I
- Get better at understanding the needs of trees
- Learn to better evaluate the condition of a tree, and make decisions about it's treatment.
There are 7 lessons in this course:
Tree Planting Techniques
Soil, Water, Climate, Maintenance, Matching a tree to the site, Local regulations, Plant at the right time, Planting techniques, Plant size and age, Container type, Buying a tree, How to plant a tree, Watering method, Transplanting a large tree, Preparing for transplanting, After-care, small feature trees, Transplanting deciduous trees, Pruning at planting, Pocket planting, Slope serration, Wattling, Planting on Arid sites, Direct seeding, Spray seeding, Trees with berries,
Controlling Plant Problems
Temperature, Frost, Winds, Acclimatisation, Tree guards, Other Tree Problems (Fire damage, Fire Resistant trees, pollution and toxic reactions, Soil contamination, Treating foliage burn, Soil rehabilitation, Trees to extract soil contaminants, Soil chemical composition, Air pollution and tree growth, pollutant tolerant trees, Pollution intolerant trees, Trees to control Urban air pollution, Dry soils, Symptoms of drought stressed trees, Dry soil tolerant trees, Trees for hot sites, Drainage problems and trees, Wet tolerant trees, Tree health problems, Resistant plant species, Choosing and using pesticides safely, Biological controls of pest and disease, Life-cycles, Tree termites, Tree injections, Tree nutrition and nutrition management, Fertilisers
Strengthening Weak Trees
Trimming, Trimming technique, Adverse responses to trimming, thinning, Bracing, temporary props, Modern bracing systems, Bolting, Rodding technique, Guy wires, How strong is dead wood, Cabling
Controlling Damage Caused by Plants
Tree damage, Tree root problems, trees that can cause problems with drains, Precautions with drains, Selecting and using trees near drains, Limiting root problems, Root pruning, Trees and the water table (Aquifers), Trees and power lines, Poisonous trees,
Tree Felling and Stump Removal
Tree evaluation systems, Calculating tree value, Tree removal, Why remove a tree, Tree felling methods, Axe, Saws, Winches, Chain saw, Controlling the fall, Different methods or removing stumps, Protecting trees, National Tree registers, Measuring tree height, Keeping a work site safe, risk assessment, Duty of care, Costing jobs,
Tolerant Plant Species
What to plant where, Tree data required, Influence of trees on buildings, Species suitability, Planning considerations, Harsh environments, frost protection, Frost resistant trees, Sun protection, Mulching, Fencing, wind protection, Wind tolerant trees, Soil degradation, Saline tolerant trees, Lime tolerance, Acid tolerance, Hardy trees for inner city, Review of several major genera (Acer, Fraxinus, Pinus, Quercus,
Establishing a Tree Plantation
Windbreaks, Windbreak design, Choosing windbreak species, Designing tree plantations, Producing drawings to scale.
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.
Explain how to plant a specified advanced-sized tree on a specific site.
Explain tree injection, including the technique and applications.
Identify situations where trees require strengthening operations to be carried out.
Compare different ways to control roots which invade underground pipes.
Calculate the cost of removing a specified tree.
Determine appropriate tree species suited to a specific visited site.
Devise a method for removing a tree, including tree felling and stump removal.
Analyse different specimens of mature trees, from each different genera, to detect any patterns in problems occurring in those trees.
Develop criteria for the establishment of a tree plantation on a specific site which addresses; site restrictions, cost and function.
Contaminated Land Can Present Both a Challenge and an Opportunity!
Through out the world many areas including industrial sites, home-sites or even the natural environment are degraded due to chemical residues. Pesticides, builders rubbish, land fill, industrial waste or some other residue may have contaminated the site. It may be that management practices have changed drainage patterns, or increased the amount of water or waste moving onto or across a site. Or it may be as a result of poor practices in the past.
Chemical soil contaminants include arsenic, benzene, paint containing lead, fuel such as petroleum and aviation fuel, heavy metals such as cadmium and chromium found in batteries, pesticides and herbicides etc.
Some tree species in particular can be difficult to grow on a contaminated site, but appropriately selected tree species can perform well enough to survive; and perhaps well enough to help with the rehabilitation of contaminated soils in an area.
In areas where plants are growing on a contaminated site, soil chemical contamination can cause foliage to discolour or burn; but be sure it is contamination - there are other things that can also cause foliage burn. Foliage may discolour or burn because of the following:
- With some plants, wet foliage is likely to burn in direct sunlight.
- Conifers which are watered on the foliage on a hot day commonly develop burn marks later.
- Generally plants with soft or fine foliage are most susceptible to this type of burn.
- Think about when the burn appeared. Was it straight after a hot day, and was the foliage wet then?
- The symptoms would occur on the parts which were wet and most exposed to the sun (except in severe cases, burn would only be on one side).
- Burn will be worse on the tender growth (usually the young leaves or growth tips).
- It will be worse where the plant gets greatest exposure to the sun.
- Symptoms will show very quickly (by the next day).
- Shade cloth is a good way of protecting plants from severe affects of sunburn - if a plant is exposed and continually burning, then it is probably not planted in the correct position.
- Chemicals in the soil can cause a more generalized burn (ie. growth tips or young foliage spread all over the plant show burn, unlike sun burn which might be on one side only).
- Consider whether the soil might have been polluted by a previous owner or if chemicals may have washed in from a neighbour's place.
- The effects will be worse in badly polluted areas, so if you suspect pollution from a nearby factory, look at plants growing closer to the factory; they should show more dramatic symptoms.
- Overuse of many types of insecticides or fungicides can burn foliage they are sprayed on.
- Spraying on a hot day can cause foliage burn.
- Excessive chemical residues in the soil.
- Look for the effect on the foliage most exposed to the chemicals.
- Too much fertiliser can burn root tips, and in extreme situations, cause burn marks on foliage.
- Fertiliser burn is more likely in hot weather when many fertilisers become more soluble due to the warmth.
Treating Foliage Burn
- Damaged foliage cannot be repaired. It can only be removed to prevent decomposing tissue spreading infection to healthy tissue.
- Feed damaged plants, unless the burning is the result of over-feeding, and try to look after them well so as to promote rapid rejuvenation.
- Avoid making the same mistake again by not putting susceptible plant varieties where they could suffer the same fate.
- If the problem is due to damaged soil; select more tolerant plants for the damaged site; and avoid any further soil damage.
SYMPTOMS OF PLANT ILL HEALTH
Chlorosis is a condition where leaves cannot produce sufficient chlorophyll. Therefore they are generally pale, yellow or a whitish-yellow colour. The plant is unable to produce carbohydrates through photosynthesis. This condition generally requires treatment.
Causes of Chlorosis can include:
- Poor drainage (waterlogging)
- Mineral deficiency in the soil (eg. magnesium or iron).
- Damage to roots
- High alkaline soils
- Exposure to sulphur dioxide
- Herbicides and pesticides
Premature Leaf Drop
A variety of factors can cause leaf drop in trees. These include:
- Boron toxicity or overfertilisation.
- Prolonged exposure to air pollution. This can make trees more susceptible to foliar insect attack.
- Gall aphid or mite attack
- Over or underwatering
- Sulfur or Boron toxicity
Branch Die Back
Branch die back can be the beginning of tree die back. Causes of branch die back include:
- Fluctuations in soil moisture in weather cycles
- Mechanical damage to roots
- Rapid changes in temperature
- Soil pathogens such as Phytophthora and Honey Fungus.
- Nutrient deficiency or toxicity
Reduced growth or “decline” in plants is the general gradual reduction in growth and vigour in a plant. This can be caused by the following:
- Bacterial Infection
- Plant viruses
- Calcium, Nitrogen or Phosphorous deficiency