In terms of the amount of fence treatment required, yes it does. This is because rough sawn woods are very porous and absorb more treatment than smooth planed wood. This should be taken into consideration if treating a large area of garden fencing. Our Barrettine Premier Wood Preservative page has colour swatches that show the potential colour difference between rough and smooth wood. This illustration should only be used as a guide and not as a substitute for doing a test area.
Because rough sawn fence panels absorb more wood finishing product than smooth planed wood, any colour pigment in the product is likely to look stronger or darker than it would on a smooth piece of timber. Always do a test area to be sure of the colour and final finish before starting any project. It's also worth noting that although wood finish colours may initially look stronger than expected when applied, they usually 'tone-down' after several weeks or months of weathering.