There is a species of fly called Rhagoletis completa which destroys walnut trees, and it appeared already in Hungary years ago. However, it seems now that it spread everywhere in the country because 93 pc of the farmers told an agriculture-focused Hungarian news website that it causes significant damage to their trees.
According to agroinform.hu, the fly damaged trees in the Western part of the country in the last few years, but it has spread everywhere in Hungary by now. The website received 4,700 answers on its relevant questionnaire. That means that they have a comprehensive enough panorama about the damage that Rhagoletis completa does. The spread of the fly was so quick that
67 pc of the farmers never even encountered this question before.
Among the less-endangered counties of Hungary, there are only two, Szabolcs-Szatmár-Bereg and Hajdú-Bihar, on the Eastern side of the country. However, 43 and 36 pc of the respondents knew about the problem even in these two regions.
Ten pc of the farmers do not know what to do while 41 pc try to collect the fruit before the flies can harm them. If they manage to separate the shell in time, they can save the walnut inside. 25 pc said that they could not do anything, so they decided to keep the trees to provide shade during the summer, and
they hope that they will be able to buy an efficient pesticide soon.
15 pc is thinking about spraying, and nine pc would rather cut down the trees.
Only eight pc of the respondents have more than ten trees, but only 35 pc of them would spray their trees to extinguish the vermins. That is because they would need machines to do so, and the perfect timing is also imperative. Others collect the walnut and destroy it, and some bought poultry to prevent the larvas from getting into the earth. 26 pc of those having ten or more trees said that they use bug zappers.
Bence Bolyki, CEO of Agroinform, said that nobody should worry that walnuts would disappear from Hungary because big farmers would be able to protect their trees. However, those having some trees in their garden will probably have to accept that they will no longer be able to eat their fruit.
The Rhagoletis completa is indigenous in the USA and Mexico,
but it popped up in Europe in the ’80s while it first appeared in Hungary in 2011.