Gradually moving from a mixture of sugar maples to red maples, this year I am 100% red maples. Since my collection has been predominantly red, my syrup has been dark from day one and that is true this year. I have also found that as I increased my mix of red maples that my filtering has become increasingly challenging. This year, with 100% red, and late in the season (when my syrup tend to filter more slowly) I can now no longer use a felt/paper combination on my vacuum filter press. I use a shop vac to draw down a CDL 12” filter press. It used to work well in previous years, when there was a component of sugar maples. This year, at this point, I no longer can use the felt (or whatever that material is) and must use several layers of the paper (it’s not really paper either) filters.

I like to mix in the diametric earth (again, not sure what it is called) into the syrup before I filter it but could not do that as the filtering slowed down.

My theory is that red maples, being softer, have an easier time of passing minerals between the cells and passing it into the sap. Hence, my conclusion is that red maple sap is dirtier than sugars. Has anyone else had that experience or can suggest another reason?