Some Local Autumn Bugs

     We often tend to call insects "bugs", but there is an order of insects, among the many orders of insects, that really are true bugs.  Here in the Middle Atlantic States there are two common species of seed bugs and one abundant kind of plant bugs, all of which are somewhat similar.  All three of these attractive and interesting species are about the same size, have flat, oval bodies and similar colors and color patterns that make all of them attractive.  The seed bugs include the large milkweed bugs and small eastern milkweed bugs.  And eastern box elder bugs are the common plant bugs.        
     Large milkweed bugs and small eastern milkweed bugs both eat the maturing and mature seeds of milkweeds in milkweed pods.  These species must be competitors for the same foods in the same open, sunny habitats, including meadows, fields and roadsides, in most of the United States.  Direct rivalry for food like this is unusual in nature.  Perhaps these two bug species have a way of reducing competition for food that I'm not aware of.
     Many times I have seen little groups of both kinds of seed bugs on milkweed seed pods during summer and into autumn in this area over the years.  The adults of these two milkweed bug species are red and black on top and have nearly similar patterns of colors.  Large milkweed bugs are four-eighth to five-eighth of an inch long while the smaller one is three-eighth to four-eighth of an inch long.  Both kinds lay eggs on growing milkweed plants and the resulting bugs live in groups on and in milkweed pods where the seeds develop.  Both species have one or more generations each year, depending on the latitude where they live.  Bugs in The South will have more generations than those in the north.  And the adults of the last generation of the year overwinter and emerge the next spring ready to lay eggs.
     The nymphs of these seed bugs are different in appearance, however.  The young of the large species are orange-red with black legs and antennae.  The offspring of the small kind resemble the adults, except in size.
     Eastern box elder bugs live in deciduous woods along creeks and feed on the sap of box elder trees, also known as ash-leafed maple trees.  Ash-leafed maples thrive best on bottomlands along waterways in most of the eastern half of the United States. 
     When nights get cold in October in the local area, I see thousands of fertilized female box elder bugs in masses here and there on rock outcroppings, stonewalls, the walls of buildings, around holes in trees and fence posts, and anywhere else they can find protective recesses to pass the coming winter in relative safety.  Most people don't want these insect swarms on the outside walls of their houses, though box elder bugs never bite or sting, or eat anything through winter, therefore causing no damage.    
     Box elder bugs are three-eighth to five-eighth of an inch long and red and dark on top, with color patterns a little different than those on seed bugs.  Their nymphs are red, but add black to their coloring as they grow.  Females lay eggs in crevices on the bark of trees and there are one or two generations of this bug every year.
     These seed bugs and box elder bugs are attractive, harmless to us and, actually, rather interesting.  Watch for them this fall and succeeding summers and autumns.