Attack of the aphids

Last week I announced that there are aphids in the greenhouse.  By now there are more, lots more and we have begun a three-pronged attack on them.  But first, it's important to know just who we are dealing with.

The foxglove aphid, Aulacorthum solani, has a huge range of host plants and can transmit 45 diseases, so it's pretty bad.  The adult aphids are 1.5-3 mm long and are dull green or brown.  Their antenna are longer than their body and have dark joints.  Their legs also have dark joints and their cornicles are dark at the ends.  The picture below (which I did not take) shows all these characteristics really well. 

Photo taken by Andrew Jensen (aka Aphidman)

They like to colonize deep in plants on tender, young leaves.  I definitely found this to be true.  See how gross the young spinach leaves look?  What really kept me up at night is the reproductive rate of these aphids.  In just THREE DAYS the population doubles in a 55 degree environment.  How could I sleep when I knew aphids were busy multiplying that fast?  Happily, we've started attacking the problem.  You can look forwards to the next installment of "Attack of the aphids."

Sources: AphidID, Jandricic et al., 2010, RIS