Why Is My Fig Tree Covered With “Sawdust”?

Question

I have a large fig tree in backyard that has been beautiful and fruitful for years. This year no leaves and the branches were dried out. Then about 4 weeks ago it started to send up leaves and new branches from its roots. Now the leaves are covered with what looks like sawdust but doesn’t brush off. The old branches are dry and hollow when broken off. The new branches seem healthy except for this “sawdust”. Anybody know what’s going on?

Answer 1

The suckers are coming up because the tree is stressed, here is more information:
http://www.ipm.ucdavis.edu/PMG/r261300611.html