Now when I see them I think 'what a feast for my beneficial insects'. The buggy weeds are close to the insectary and today I spotted more ladybugs, a syrphid fly and some parasitic wasps.
I never knew what to call it except the 'horrid weed'. But I discovered this wonderful resource from UC Davis Integrated Pest Management site with a weed identification section that is amazing. It has excellent photos of plants at all stages, from seeds and seedlings, to mature plants, and closeups of leaves and flowers. I found my weed right away from the easy to navigate site. I now know it's a Bristly Oxtongue.