TREE HEALTH DIAGNOSIS - A SELF HELP GUIDE..

Unfortunately trees can be hard things to understand and simply saying, "the leaves are brown and falling off" could relate to a whole host of problems. So I thought what may help is a checklist of things to go through to provide readers with as much detail as possible to help in diagnosing any problems.

CAUSES OF ILL HEALTH IN TREES:
Basically (and I mean very basically) there are two causes of ill health in trees. Biological and non-biological.

BIOLOGICAL AGENTS
Fungi
Bacteria
Viruses and viroids
Insects
Birds
Mammals inc. man

NON-BIOLOGICAL AGENTS
Extreme weather - Hail, rain, cold, heat, frost, sun-scorch etc.
Poor soil conditions - Drought, waterlogging, compaction, nutrient deficiencies etc.
Chemicals - Weed killers, fertilizers, fuel spills, poisons, gasses etc.
Other - Poor handling, mechanical damage, bad pruning practices, fire etc.

All these things, and more, can have a negative effect on trees that sometimes won't show symptoms until years after. Trees are living things that will try and deal with any ill health problems that you generally won't even know about.

SOME COMMON PROBLEMS WITH TREES:
Soil conditions
Drought - Pretty obvious. Nothing you can do except keep the tree watered in hot weather. Drought can also be brought about my extremely windy conditions.
Waterlogging - Overwatering can be a serious problem in trees. Trees get oxygen from the ground as well as the air. If the ground is waterlogged the tree cannot get this soil air. Bacteria then form in the waterlogged soil and poison the tree. Do not overwater your trees.
Soil compaction - Hardened soil around the tree makes it harder for rain water to penetrate the ground and reach the roots. Aerate the ground around the tree's dripline to alleviate this problem.

Mechanical damage
Pruning - Countless times I have seen trees badly pruned by their owners and the problems associated with it. Pruning should only be undertaken if absolutely needed. Do not leave stubs or rips and do not cut branches flush to the tree. All these things make it harder for the tree to defend itself against infection. Take a look at this page for a pruning guideline. http://www.htlcservices.com/images/Tree_20Pruning_1_.gif
Lawn mowing - Take care not to damage the base of the tree when using a lawnmower or strimmer. The bark is the protective layer of the tree that keeps out infections, as well as protecting the trees nutrient transport system (cambium, xylem & phloem).


INFORMATION REQUIRED TO MAKE A DIAGNOSIS:
Please provide as much detail as possible when asking for help with dignosing a problem. Not only will it help in providing you with an answer, but it will help others who may be suffering the same problem. As I mentioned before, a lot of symptoms a tree shows can relate to a number of problems. Misdiagnosis could be as equally as bad as no diagnosis.

The Tree
Species - inc. varieties and cultivars
Location in its setting - Garden, roadside, waterside, sheltered, open?
Age or date of planting
Cultural operations - Any pruning, herbicide or fungicide carried out within the last few years?

The Site
Soil type and condition - Free draining, waterlogged, clay, silt, acidic, alkaline, previous uses?
Changes - Any excavations, additions or changes in soil levels within the last few years?

The Problem
Provide as much detail as possible about the symptoms inc. when first noticed, how widespread, how severe, parts of plants affected. Also look out for fungal bodies, insects, abnormal growths on the tree such as galls, exudations etc. Provide a photo or photos whenever possible.

I really hope this help you in diagnosing a problem and finding a remedy.

(P.s. Maybe this can be sticked so forum users can view this first? Just an idea.)