Apple Tree Diseases. ProblemDiseases of Apple Trees and how to cure.
The first thing to
assess when you think that you have a diseased apple tree, is
whether in fact your apple tree is actually 'diseased' or is
affected by a 'pest'! A pest is a living insect or mite, whereas a
disease is normally a fungal infection. It can also be a virus.
Basically, if it has legs - it is a pest. An insect
of sorts that can be treated with an insecticide. Insecticides are
no use whatever in treating diseases. (However, some diseases are
spread by insects, so there is sometimes a case for treating a
disease bearing insect!) Some pest look like
diseases, which does not help. Woolly aphid in particular, is often
confused as a fungus because of its cotton wool appearance.
Fortunately, there are not too many diseases that commonly
affect apple trees, and the identification can normally be positive. Most of
the diseases on Apple Trees are caused by fungus, and can be controlled by
fungicides or other physical control.
The most common disease affecting
apple trees is some form of Canker
or other. The image shows an early attack, which can develop into
large lumpy growths - affecting the tree quite severely unless
Apple Scabis a fungal
disease, and normally appears in the later part of autumn, or early
in spring. It shows as brown or black pimples on leaves, and
ultimately to the fruit of the apple tree.
It is spread by wind, so can easily take hold if not checked in
early stages. Leaves will not stay on the tree, and signs on the
apples are maturing unevenly - eventually cracking and spoiling.
The scab looks as its name sounds!
Prune any affected areas and burn the debris.
Affected fruit should not be stored. There can be lasting damage
to the apple tree from Apple Scab Disease.
Fire Blight Disease is again aptly named, for the
apple tree will look as though a fire has been started nearby -
scorching the foliage up one side of the tree.
It is a serious disease that can also affect many
other plants of the same genus as Apples - The Rose family.
(Pyracantha, Hawthorn etc are also affected.)
Affected young shoots will wither and die - as
will any flowers.
Prune back hard, any affected branches and burn
Black Rot of Apples
Disease will be visible on mature fruit - just as they are nearly
ready to harvest - typical!
Often, the apple has already been wounded by some
physical force or other. This will include bruising damage as a
result of windy conditions.
The disease is first noticed as small brown spots
on the apple fruit, which will then grow - turning first dark brown
and then black!
If caught early enough, then the fruit can be
treated with a sulphur spray.
It can spread to the bark of the tree and will
overwinter - ready to affect the tree in the spring growing season.
A good fungicidal spray in early winter will help this and other
fungal diseases of apple trees.