Hey there.
You could hide this with CSS:
.post header p{
display:none;
}
You can add the CSS to your themes stylesheet.
If the theme is not one you made, then you may wish to use a child theme for this additional CSS. That way you’re protected when you come to upgrade.
Read more about Child Themes here:
http://codex.wordpress.org/Child_Themes
http://premium.wpmudev.org/blog/create-wordpress-child-theme/
You can instead use a plugin if you like:
http://wordpress.org/plugins/custom-css-manager-plugin/screenshots/
http://wordpress.org/plugins/my-custom-css/screenshots/
http://wordpress.org/plugins/pc-custom-css/
http://wordpress.org/plugins/imporved-simpler-css/screenshots/
Else it’s originally created in the theme’s function.php line 180. They check if the function exists first so we could do this a child theme using a new functions.php file:
function orange_posted_on() {
}
It’s basically a blank function so that it instead does nothing at all.
Hope this helps. 🙂
Take care!