The Colorado Potato Beetles have started to hatch
Whenever pupae are found, we always prepare for the possibility of them developing into adult beetles, and inspections will be carried out regularly on the infestation spot. On the basis of these inspections it has been possible to calculate that the time it takes for the beetle to develop from egg to adult is about 42 days.
During a warm summer like this, the development of the Colorado beetle is fast, so there is reason to fear that a new generation of beetles able to hibernate could also develop somewhere else. Hatched adult Colorado beetles should be found in the potato crops before they burrow back into the soil to hibernate. It is difficult to find Colorado beetles while in the pupae stage, but adult beetles can be found on the potato leaves. On warm and sunny days especially, the beetles gravitate towards the higher parts of the potato plant to warm up.
During the whole week an easterly air flow has prevailed, and with this individual beetles of the new generation may have migrated from Russia, especially from the north side of Ladoga to North Karelia, but also from the Viipuri area to South Karelia. However, the risk that the summer generation might migrate is not very high, as the beetles will stay in one place if there is sufficient nutrition in the hatching spot.
For the monitoring of the Colorado beetle, the emphasis has been put on securing the reporting of any new findings and on surveying the earlier findings (in Parikkala and Kesälahti) for hatching adults. In addition, the infestation spots of 2004 and 2005 have been inspected and no beetles have been found. This shows that the control measures have been effective.
The monitoring of the beetles has to continue until the potatoes are harvested. It is very important that both commercial potato growers and home growers are actively looking for the Colorado beetles. Contact information for reporting of any findings and photos and information about the Colorado potato beetle may be found on Evira’s web pages at the address: www.evira.fi/koloradonkuoriainen. The general emergency phone number for reporting the findings is 0400 442 209.
For additional information:
Senior Inspector Olli Elfving, Evira, phone 020 77 25048 and
0400 808 522
Senior Inspector Atro Virtanen, Evira, phone 020 77 25047 and 040 7049607