Are there any Forest Fills that aren't just individual trees grouped together? Looking for something like the old D&D 4e Nentir Vale forests.

https://vignette.wikia.nocookie.net/tahlequahpointsoflight/images/9/92/Official_Nentir_Vale.jpg/revision/latest?cb=20161122224752

One big Forest with lines that imply trees and shadows on the edges. It's super common with hand drawn maps and I'd like to do something similar with CC3. Any annuals or places I should look at?

There's also the Fantasy Realms style from Annual Vol. 3, the February 2009 issue, which uses only a simple fill style and sheet effects to achieve a look similar to the D&D Forgotten Realms maps from the 1980s.

Comic Book Maps in Annual Vol. 7 for June 2013 has a similar type of fill to your Nentir Vale link, but there are linear "tree trunks" extending from the lower sides of the woodland areas as well.

You might try the Volcanic Islands set from the April 2014 Annual instead, although the woodland fills are rather "busier" than your example.

However, I think you may find the Ancient Realms Annual from October 2015 the nearest equivalent to what you were hunting for.

Good luck!