November 06, 2004
As soon as trees are harvested and before heavy rains is the time to spray for peacock spot and olive knot. Peacock Spot, also known as olive leaf spot, is caused by the fungus spilocaea Oleaginea. Copper fungicides are the mainstay for control. The fungus causes leaf drop which robs the tree of vegetative energy leading to smaller crops and poor growth.
Olive Knot is caused by the bacteria Pseudomonas Savastonoi. It enters cracks in the plant at the site of pruning, leaf scars, etc, causing a gall like "knot" to form which can girdle and kill twigs and branches. Copper sprays control the bacteria.
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