Missouri Master Naturalists- Springfield Plateau Chapter

Tuesday, July 14, 2020

Pretty Pests

Yellowstriped armyworm - Becky Swearingen

Our photographers have been busy collecting specimens, not always species we welcome.  Becky Swearingen started it with the cute cat above.  This is a yellowstriped armyworm (YA).  The name alone doesn't have a warm and fuzzy ring to it and its official name, Spodoptera ornithogalli, doesn't exactly roll off the tongue.

YA formal portrait - Featured Creatures

The moth is actually beautiful close up.  It is a little less than an inch long and would be easy to miss in nature.  This photograph below by Kevin Firth was taken at a mothing event where it was clinging to a white sheet.


"The term "armyworm" can refer to several species, often describing the large-scale invasive behavior of the species' larval stage. It is regarded as a pest and can damage and destroy a wide variety of crops, which causes large economic damage."  As "army" implies, they tend to occur in large numbers. 

A female can lay up to 3,000 eggs with as many as 500 eggs in one mass which is covered with scales from the moth's body.  Early instars may feed in masses before spreading out on their own to munch tender leaves.  Many of our preferred crops are tender and juicy.  In southern climes there may be three to four generations.

YA is native to the Western Hemisphere including the Caribbean but is only considered a pest in the southeastern US.  UFL Featured Creatures lists over 20 "crop" plants that it consumes in addition to various "weed" species.  While these categories mean a lot to us, old YA could care less.