Why is my mower leaving streaks (clippings) on the lawn?

[lawn mower fanatic]

You guys have really good eyes. So I checked and I did put a 18'' blade on a 19'' mower. Now I know how to fix it.
:thumbsup:

Glad you figured that out. :thumbsup: I would say it might be a combination of that and a dirty mower bag. Because my mower started to do the same thing and the fabric of the bag needed to be cleaned.