I am getting overrun by two weeds this year, well two additional weeds
anyway.

Thing is I never saw them before this year, so I'm wondering where they came
from (bird droppings??).

At any rate the weeds are reasonably easy to remove, but they are just so
aggressive

Anway, here are some shots,
First, the garden troll is threatening me for invading his territory
http://photos.imageevent.com/eigenve...e/P6190197.JPG

Now, these things appeared last year, utterly out of the blue. Simple to
pull up, but reproduce like rabbits
http://photos.imageevent.com/eigenve...e/P7050206.JPG
http://photos.imageevent.com/eigenve...e/P7050207.JPG
They have purplish/green leaves and stems and the leaves resemble pentagons.

These are small, really easy to pull up, but choke any plants they get
around.
http://photos.imageevent.com/eigenve...e/P7050209.JPG
warning - its a huge image
http://photos.imageevent.com/eigenve...s/P7050209.JPG