Ragweed or Goldenrod?

I can tell fall is coming after all, because I spend my days tanked up on Zyrtec and Sudafed and my nights dreaming Benadryl dreams.  I don't know how the pollen count is where you live, but it's terrible here.  Ragweed is our main culprit, sending the pollen counts skyrocketing for almost a month now.  But the goldenrod's blooming now too, so we're being warned not to blame goldenrod.  It's not the goldenrod's fault, just because it looks like ragweed.

Bad guy or good guy?

I doubted my ability to tell one from the other.  And I couldn't let it go, because I kept driving past fields and fields of bright yellow flowers, which were probably goldenrod (right?), but could be ragweed.  I looked at pictures on the internet.  I looked at my handy weed field guide.  Informative, but still, I was unable to identify those weeds blooming their heads off in our area fields.  I dreaded walking through it, in case it was ragweed, but I had to find out.

Goldenrod?

I think it's goldenrod, all right, Solidago canadensis.  The leaves are lanceolate and the plants are taller than ragweed usually is.  Except for that giant ragweed.  Did you know there was a giant ragweed?  Time for a closer look...

Leaves like goldenrod and brightly colored...

Yep.  Looks like goldenrod.  These plants don't seem to have the reddish stem of ragweed, and the flower heads lean over and downward.  I seem to remember that ragweed holds its flower heads straight up.  Probably safe to venture closer.  Oh no!  Some have flowerheads standing straight up!

Young goldenrod or mature ragweed?

And here's something else.  Is this a goldenrod plant that's just beginning to flower?  Or could it be ragweed? 
Now that I'm home, I can't remember if this plant had the raggy leaves or the nice, neat, narrow leaves.

Goldenrod!

Ah, now I feel better!  Ragweed is wind-pollinated, which is why it has to release those billions of pollen grains every year.  Goldenrod is pollinated by sweet little honeybees, because their pollen grains are too heavy to be carried by the wind.  (Of course, bees also visit ragweed for the pollen, but I'm hoping for the best!)