(copied from a website called ecodog I believe...)
I do not know the exact time...it's been some time since I talked to someone who had been over there, but I think it might have been from noon on.
North Clackamas Park: Big park with lots of space and a large dog run area with lots of regulars. Location: Off of Rusk Rd and Hwy 224. Directions: Take Hwy 224 (Milwaukee Expressway) to Rusk Rd. Turn onto Rusk Rd (the side with the big church) and follow road for 1/4 mile (just past the church). Turn right and follow this road all the way back to the Milwaukee Senior Center and the park's parking lot. Dog run area has water and bowls, and often visitors bring plastic bags for everyone to scoop with. Lots of regulars. Good place for dogs! (Thank you Heather Andrew)