Answer;
Pioneer, Dryas, Alder, and Spruce
The order of the stages of primary succession beginning with glacial retreat as seen at Glacier Bay, Alaska, are Pioneer, Dryas, Alder, and Spruce.
Step-by-step explanation;
-Primary succession occurs in lifeless areas, the regions in which the soil is incapable of sustaining life as a result of factors such as lava flows, newly formed sand dunes, or rocks left from a retreating glacier.
-The order of stages of primary succession begining with glacial retreat is; Pioneer (make soil), dryas (build up soil), alder(provide nitrogen), and spruce (highest nitrogen, shade out alders).