f your fleece has a lot of veg in it, it may benefit from an additional pass through the carder. This fleece is first shearing alpaca. The fleece is loaded with a great variety of vegetation - some of it tiny, sharp, stickery things which make it very unpleasant to handle. The first picture shows the fleece after washing and picking.
By taking my time and feeding the carder slowly, a preliminary pass through the carder (to a batt) opens the fleece much more than the picker can. Essentially I use the carder as a very fine picker. The next picture shows the fleece after the first pass through the carder.
And then one more pass through the carder to make roving. It isn't perfect but it's much cleaner than it was.