May-June for ticks here in eastern Washington. Years back, I had taken my lab, she was a 3month(?) old pup at the time and my malamute to a lake. I had to walk through a wheat field that was recently plowed, followed by an area of thick grass and brush. When I made it to the shore and looked at both dogs, they had what looked like thousands of them crawling in and out of their fur, I looked at my pants and I was covered as well. I walked back to the plowed field and tried to get as many off as I could before heading back to my truck. I ended up striping down to my underwear for myself and managed to get a number of them off the pup, but my malamute was gonna need some frontline. The next day after treating both, there were so many dead or dying ticks in their kennel it was insane, I've never seen anything like it.