Why does whole leaf tea leave a residue in the cup? I purchased this nice whole-leaf oolong tea this afternoon.


I steeped it in 200 F water for 3 minutes (as directed) in my tea steeping basket:


And when I pulled out the basket, there were some uninvited guests remaining:


Did I do something wrong? I thought this was the kind of results to expect from tea "dust" that might be expected in a bag, but this is whole-leaf tea. Do I need to pre-sift my tea, or something? I'm afraid that as these remnant sit in the tea, they will make it bitter.
This is normal. Even with whole leaf tea, it's a dried (and cooked) product. You're going to experience some "crumbling," and, in my experience, these grounds are more common with loose leafed tea than with dust-in-a-bag. Just pour out the last of your cup--or get used to the texture.