Major causes of tree stress are problems associate with their root systems. Unfortunately, especially in urban environments, much of this is caused by our actions. I will cover the prevention of this within the tree care section of the site.
Problems associated with a trees root system they can be varied. Dieback of the crown can be a sign of root decay as can fungi at the root collar or growing above the trees roots. Whilst the fruiting bodies of fungi can give us an indication that there may be problem it must also be noted that many fungi exist in harmony with trees, creating essential nutrients etc (e.g. mycorrhizal fungi). Other symptoms of root problems can include early autumn colour change, yellowing of foliage, and early leaf fall. Expert analysis is essential.
Man Made
Sometimes tree problems are unfortunately associated with our own ignorance (carrying out incorrect procedures), accidental damage or even vandalism!
This Beech showed signs of early leaf colour change (often associated with root problems)
