".....to see which plants do better and to see how the fines affect the plants in general ."
Yes, it was understood but you said above that you wanted to see how the fines affect the plants, so wondered if you were thinking your mulch would have the same effect whereas it won't necessarily if the particle size is different. Having said that, based on Michelle's post that was linked to above, pine fines can be anything from coffee grounds to 1" in size.
