This year is not a good year for olive tree farmers in Spain. A pathogen named Xylella fastidiosa has shown up and this is a gigantic problem. Xylella fastidiosa has been dubbed by one Spanish newspaper as the “Ebola of olive trees”. The European Union has also described this disease as “one of the most dangerous plant bacteria on the planet.” This disease also has no cure so once a tree gets it that tree is done.
Spain has an estimated 340 million olive trees that supply roughly 50% of the world’s olive oil. This in and of itself is not good for anyone who cooks with olive oil. This is also a huge problem for Spain’s economy. This bacteria has appeared in Valencia, Spain and of the seventeen sampled almond trees 12 were infected. The trees did not appear to be symptomatic but their almond production was reduced. While it did not appear that any olive trees were infected all trees within a 300 foot radius of an infected tree were cut down. The trees are also being sprayed with insecticide to try and keep the insect vectors of this disease from infecting the trees in the first place. Additionally, Spain and the rest of Europe are facing another threat. a subspecies of this called Xylella fastidiosa fastidiosa which is native to central america and infects grape vines has appeared in Mallorca,Spain.
Last year in Italy over 100 million trees were killed leading officials to chop down tress in order to try to stop these infections. Italian Environmentalists were furious that ancient olive trees had to be cut down in order to try and stop this disease. In the end a prosecutor tried launching a criminal suit against the researchers claiming that they caused the disease outbreak in the first place.
Xylella fastidiosa is found in the xylem tissue in trees, which is responsible for moving water though the plant. In these trees the leaves dry out and soon appear to be scorched. The bacteria stops water from reaching the leaves as well as the other structures in the plant dehydrating them and usually killing them. The vectors for this disease are the spittle bug, cicadas and sharpshooters which feed on the xylem of the plants. In the united states Xylella fastidiosa has infected pecan, almond, blueberry and other trees in California and in the south.