Later that day, one of the quills pointed through the skin. Apparently it was deposited inside her mouth and worked its way out through her muzzle. Steve was able to pull it out. Note the barbs, as seen under a microscope: 
The portion pulled out was about half an inch long, as seen here lined up with a ruler:
On Saturday's ride, Daisy had the misfortune to get under Boss's feet when he was turning, for the second time this week. The first time, she was lucky because they were in a bog and she wasn't hurt. This time, she got her foot scraped, but otherwise seemed okay. She squealed,though. I'm sure it smarted.After the ride, I noticed another quill point had appeared in her swollen area. Steve grabbed his trusty hemostat and pulled out yet another quill, also one that was deposited on the inside and poked its way out on her muzzle. Here is the swelling on Saturday evening:
Daisy has had a difficult week. We can only hope that’s the last of the quill remnants, but probably not.
