Often brought back from vacation: imported animals threaten native plants

Often brought back from vacation
Introduced animals threaten native plants

05/12/2023 4:54 p.m

In addition to the consequences of climate change, there are a number of other dangers for the plant world. This includes pests and pathogens from other regions. These are often brought in by holidaymakers or by ordering plants over the Internet.

According to experts, increasing international trade and tourism are increasing the risk of dangerous pests for the local flora. That points to that Julius Kühn Institute (JKI) in Braunschweig towards International Plant Health Day on May 12th. As the JKI scientist Katrin Kaminski explains, significantly more shipments in intra-European trade have been traced in recent years because they came from places with outbreaks of harmful organisms and were suspected of being infested.

According to Kaminski, it can be assumed that the number of unauthorized and uncontrolled herbal souvenirs brought back from long-distance journeys will increase with the number of travellers. “Plants and fruits are regularly confiscated during passenger checks at airports,” said the graduate agricultural engineer from the JKI Institute for National and International Plant Health Affairs. However, only random checks can be carried out, so that the absolute number of pests introduced in this way is not exactly known.

The Braunschweig facility belongs to the Federal Research Institute for Cultivated Plants and wants to prevent dangerous harmful organisms from being introduced. If this does happen, the scientists help to take effective measures to eradicate or limit the infestation. But the topic has a direct connection to many people. “Because if you order plants on the Internet or come home from a long-distance vacation, you can unknowingly contribute to the spread of such harmful organisms,” says Kaminski.

Pathogens also stick to shoe soles

The institute describes simple ways of transmission: If someone walks across infected soil on vacation, for example, it is possible to drag the animals along in the profile of their hiking boots and, in the worst case, transmit them at home on the next hike. Thorough shoe cleaning should therefore be done before the return journey. “For similar reasons, it’s not allowed to bring fruit, vegetables or plants home from abroad,” says Kaminski.

The Federal Ministry of Agriculture cites the spotted lantern bearer cicada as a negative example. The cicada, which originally comes from Southeast Asia, has a very high potential for damage, since it infests not only fruit trees but also vines, hops and various tree species and multiplies very quickly. In the USA and South Korea, the pretty but dangerous insect causes very high damage. “We could save a lot of damage to agriculture and forestry as well as to our nature and native biodiversity if we managed to prevent immigration to Europe and Germany,” it says on the ministry website.

As an example, the JKI refers to the spotted wing drosophila, which according to the institute was found in Germany in 2011 and has since spread widely. This can hardly be controlled because the insect species can cope well with the climate and can spread quickly by itself. One consequence is that orchards are netted to protect orchards.