Did you google 'hawthorne flowers' and click on 'Images'?* Doesn't look like it to me, but hawthornes are very variable and will cross breed.* Try asking at the UBC Botanical Garden.* http://www.ubcbotanicalgarden.org/fo...splay.php?f=38
Here's their main page.* Add where you live when you register as this site is in Canada.
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.