Further research says yes. Winter 2015/2016 It was the compost pile. 2016 it was tomatoes and fall was brassica. The tomatoes grew well in that bed. I don't think there were nematodes then. How did they get there???

Nematodes can travel into your garden via soil or soil-less mixes in purchased plants, via tools that might have been used first in one area and then in another, even via rainfall and runoff. So, a previously nematode-free area can suddenly have them. It is peculiar when that happens. I've had it happen with one plant, once, and never again. Where did they come from? That is easy---probably a purchased plant. But the bigger question is where did they go after that because they weren't around the next year? Generally, nematodes are found in sandy soil and the quickest remedy is to add organic matter to the area where you found them. They don't do well in soil that is high in organic matter. If that fails, planting Elbon rye in autumn gets rid of them. They become trapped within the rye roots and die.