Climate change in the 21st century is likely to dramatically alter the growing conditions that Pacific Northwest tree species experience. It has been suggested that foresters plan for these changes by moving seed sources to locations where the seed-source environment and the future climate will be similar. Some people have called this type of seed-source movement “assisted migration” with the idea that we are helping the plants move to better suited sites faster than they would naturally. But it is important to realize that people have moved seed sources to new locations for centuries without using this term. Think of David Douglas, the early botanist, plant collector, and the one for whom Douglas-fir is named, who sent thousands of seeds back to the British Isles for propagation.