No Colorado Beetles have been found
The Colorado beetle does not occur permanently in Finland, even though they are common in areas close to Finland. Any individuals that may have overwintered will already be on the potato plants, and stormy winds and thunderstorm fronts from the south and south-east can pick them up and bring them to Finland. In addition to spreading with the air flows, the beetles can cross the borders with vehicles.
The risk of the Colorado beetle spreading is highest on the southern coast and in the south-east, but with thunderstorms the beetles can also be carried further in to other parts of Finland. The plant protection inspectors of Evira and the TE-centres started the monitoring this week. Any beetles will already be at the larval stage, which is when the traces on the leaves of the potatoes will reveal their presence. The storm in the Gulf of Finland last Thursday could have brought beetles to the southern coast, so it is worth checking the potato plants there also.
An adult Colorado beetle is about one centimetre long. There are 10 black longitudinal stripes on the yellow back and the pronotum is orange with black spots. The beetle’s semolina sized yellowy orange eggs are in tight groups on the underneath of the leaves. The larvae are orange, except for two rows of black dots on both flanks.
The adult beetles and larvae first eat holes in the potato leaves, and later they eat the leaves completely. In the home garden there can also be other insects eating the leaves of plants. The Colorado beetles only eat solanaceae, of which the potato is by far the most important.
The Colorado beetle is one of the world’s worst potato pests. Its destructive power is based on the large numbers of beetles and their fast reproduction. The beetle does not have any natural enemies of significance. In Finland it has so far been possible to stop the Colorado beetle from spreading. The insect is a harmful organism, and suspected findings have to be reported. The plant protection authorities, that is to say Evira and the plant protection inspectors of the TE-centres are responsible for the monitoring and control.
The service number for the reporting of sightings is 040 801 4407 (between the hours of 9-20).
If there is no specific need for it prior to that date, Evira will issue the next Colorado beetle communication on 30.7.2009.
For more information, please contact:
Inspector Esko Viikari, tel. +358 2077 25151
Head of Section Raija Valtonen tel. +358 2077 25040