Ballad and Common Meter (alternative iambic tetrameter and iambic trimeter)
This one's a classic, so it's no wonder it uses some of the most classic forms in all of poetry and music. "A Red, Red Rose" is written partly in ballad meter (the first eight lines) and partly in common meter (the last eight lines).
You know what that means—it's time for a little poetry lesson. Don't worry, we'll be brief, and then we'll get back to the poem at hand.
A poem in ballad meter consists of four-line stanzas (called quatrains) that alternate between iambic tetrameter and iambic trimeter. And in ballad meter, the second and fourth line of each stanza must rhyme (but the first and third do not have to). The only difference between ballad meter and common meter is that in common meter the first and third lines of each stanza, in addition to the second and fourth, must rhyme.
Now back to your regularly scheduled programming.
Burns was no stranger to the ballad, so "A Red, Red Rose" conforms pretty strictly to the form. It alternates between iambic tetrameter in the odd-numbered lines and iambic trimeter in the even-numbered ones.
Iambic trimeter, as you might have already guessed, is the same as iambic tetrameter, except there are three (tri-) iambs instead of four, as in line 2: That's new-ly sprung in June.
Now, this is all fine and dandy, but things start to get kind of weird, metrically, in the third line and beyond, when Burns starts tossing in extra syllables and other quirky things to keep us on our toes.
Like line 10 for example. It has seven syllables, when it should have six. What's up with that? Not to fear, fellow Shmoopers, we have a very good answer. Let's assume the line's first foot is not an iamb (daDUM) but an anapest (dadaDUM). If we scan the line in the following way, we have a line of neat, flowing trimeter: And the rocks melt wi' the sun.
TMI, you say? Fair enough. For all intents and purposes, it's totally cool to just notice that the third stanza is a little weirder than the rest and move on. But for all you scansion lovers out there, just know that this poem is ripe with opportunities to geek out on the meter. What about lines 11 and 12? Or line 16?
We mentioned earlier that in ballad meter the second and fourth lines of each stanza must rhyme (but not necessarily the first and third). That means the first two stanzas rhyme a little something like this: ABCB DEFE. B rhymes with B, E rhymes with E, and so on; because only the second and fourth lines of each stanza (those marked B and E) rhyme, this looks like ballad meter.
But the rhyme scheme of the second half of the poem looks like this: FGFG HIHI. In these stanzas, the first and third lines, and the second and fourth lines rhyme, making these stanzas, strictly speaking, an example of common meter.
In reality, ballad meter and common meter are just about the same thing (used in the same types of traditional, common, folksy poetry). It's just that usually a poem that is looser in its rhyme scheme (like the first two stanzas of "A Red, Red Rose" is called ballad meter, while one that is stricter (like the last two stanzas) is in common meter. But honestly, who's really counting?