What symbolism and irony did Andre Dubus use in his opening paragraph of "Killings"?
This is a bit of a difficult question, because it's possible to argue that irony isn't present at the beginning of "Killings" by Andre Dubus. However, one could also argue that there is irony in what Matt's older son says as they stand by his younger son's grave. The symbolism comes from the apple orchard across from where Frank is buried.
Matt's older son, Steve, says, "I should have killed him" as they're walking away from the grave. This could be considered ironic because he doesn't mean he should have killed Frank—he means that he should have killed Richard, Frank's murderer. Further irony could be found in the fact that when Steve repeats the sentiment, Ruth, Matt's wife, tightens her arm in response. Matt feels it. Her tension at the idea of Steve killing Richard can be considered ironic since Matt later does kill Richard—and Ruth is glad.
The symbolism of the tidy apple orchard across the river is meant to symbolize Matt's life before his son died. He lived with his wife and had three successful grown children. Steven is a bank manager. Cathleen is married. Frank had been preparing to go to graduate school when Richard shot and killed him. Matt's life is not orderly any longer, though he can still see and remember when it was.
Until he kills Richard, his life remains disordered. By murdering him and covering it up, he's able to help his wife avoid a painful trial and prevent Richard from being out of jail in only a few years. His actions return his life to its orderly state, though they don't undo the death of his son.
While the opening paragraph of "Killings" could be read as containing no irony at all, it is also possible to identify at least five possible examples of irony. Steve is identified as "Matt's older son," (his younger brother, Frank, had been twenty-one at the time of his death) at age twenty-eight, and he is described as having thinning hair. It could be argued that it is ironic that the younger brother has died first, and at a young age; moreover, it is conventionally believed that with age comes wisdom, but the first words Steve utters are "I should kill him." He even repeats those words. The pallbearers are all young men; often, this is not the case. The final potential irony is that the grave site is positioned on a hill above the Merrimack. A river view will be of no use to anyone buried in the cemetery.
It can be considered symbolic that the funeral takes place in August when summer is winding down. Matt Fowler cannot see the beautiful view of the Merrimack "from where he stood," symbolically indicating his state of mind as he buries his youngest son. It is also symbolic that what he does see is an apple orchard, a symbol of life opposing the cemetery and suggesting that life goes on.
In the first paragraph of his story "Killings," Dubus introduces readers to the Fowler family. They have not gathered for a happy occasion, but for the funeral of the youngest son, Frank. So the symbolism we see in the opening paragraph is that of a funeral: the limousine, the casket, the grave, the minister, the pallbearers, the grieving family. As for irony, I really don't see anything ironic in this first paragraph, unless you consider that the apple trees are lined up symmetrically, just as grave markers are lined up in a cemetery. But that would be more imagery than irony. Perhaps it is ironic that Steve, the oldest Fowler son, says to his father, "I should kill him." At this point in the story, the reader doesn't know who the "him" he's referring to is. So it could be ironic that he is talking about killing someone when he's standing near a fresh grave.
I hope this helps you.