Remove search box from header?

I really like the Suffusion theme so far, but I am having a problem removing the search box from the header (I want to use the search widget in the sidebar instead.

I have looked through all option pages for a way to remove it, but I have not been able to find the option. I thought I had seen the option to remove it earlier, but perhaps I am confusing this with another theme. I’ve tried out a few today.

Is there a way to remove the search sidebar from the header?

Thanks!