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Swallowtail

Q:  What could be eating the leaves on my citrus tree?  The fruit are not being touched.  Should I be worried? 

A:  There could be several creatures eating the leaves of your citrus trees.Swallowtail drying out wings  It is possible a katydid or a grasshopper are snacking on the leaves. The katydid, although very large in size, looks so much like a leaf you could easily miss them.  I captured both a male and female chomping away on one of my trees.  They are now resting comfortably in my insect collection box side by side. Growth regulators work well on these creatures or you can use the tried and true method of hand picking and squashing.  However, finding the katydids did not end the mystery of the missing leaves on my citrus.  I kept looking for the culprit. The formal word for this process of hunting for insects or disease is called “scouting.”  As I am scouting I come upon another strange looking caterpillar.  I do not kill this strange looking caterpillar immediately because I realize he will become a beautiful butterfly in the near future. The few leaves he eats will not reduce the number of oranges my tree produces nor will it destroy the tree.  Therefore, I do nothing.  I am rewarded immediately for my kindness by spotting a new arrival spreading its wings along the pine straw. It is a giant swallowtail butterfly, Papilio cresphontes Cramer. It is very vulnerable during this time as it cannot fly well enough to escape any predators.  Like all newly emerged butterflies, the wings must wait until the blood has completely filled all the veins.  This process takes a few minutes but I have a wonderful opportunity to take its photograph.  The butterfly is frightened by my camera and flutters a short distance but it cannot really escape.  You can see one corner of the wing is curled as the blood has not completely reached this area forcing the butterfly to sit still and wait.  If you see gray and white (ugly) caterpillars feeding on your citrus, remember what they ultimately will become – these beautiful pollinating butterflies.  So, for the typical home grown citrus grower, these caterpillars are a nuisance but not a real worry.  However, it is a different story for the commercial grower who has millions of dollars invested in citrus fruit production.  The commercial grower is facing several devastating diseases and therefore cannot risk having his crop diminished even by such a charming insect as a butterfly larvae.