I love b&w film, but am somewhat wary about going b&w in post. In my experience, I usually have to work such an image a lot more to make it work because I didn't mean it to be a b&w image in the first place.
The image I posted on day 7 of SiJy 2019 is a telling example - it doesn't look a lot like the original scene, I have to admit; but that shot, though interesting, just didn't pop, and making it do so ruined it in colour. Not so in b&w - but it took quite some pushing and pulling at some sliders ... The result is certainly worthwhile, but I'm not entirely comfortable with it.
I guess it'd be more accurate to state that if you want to make a b&w image, you'd better see in b&w when taking it. That said, I have nothing against going monochrome in post. However, in most cases, saving an image by going b&w doesn't work for me (exceptions only support that impression). If, on the other hand, colour turns out not to be a major point in the composition of the image, it's certainly a viable option. Still, I much prefer getting things right in-camera.
To be able to work with digital b&w, I have b&w profiles ready on most of my cameras - most of the time, I use the provided ones since I'll post-process the images anyway. Using the profiles helps getting my eye in - though after a couple of shots, I usually don't need them anymore. It's good to know that some cameras come with really nice b&w presets, though (I especially like the GR's options, but surprisingly, the output of the old M8 is really quite nice as well).
As to forest images: Subject isolation (mostly through working your DoF) and careful framing (perspective!) do the trick - colour *can* be distracting sometimes, even if it seems to dominate a scene. But doing b&w in the woods can be fiendishly difficult compared to shooting in colour and thus having a means to really make sure tones don't overlap and cancel each other's contribution to the image. You also need a strong awareness towards dynamic range with b&w - or the image may turn out really flat. Don't get me wrong, I like gentle contrast - but only when used intentionally; if not done right, the image will just look grey and boring.
I think Barrie's got a real point as far as our eyes' physiology is concerned - essentially, our colour perception sits on top of our ability to distinguish minute changes of light intensity and, thus, tiny movements. I refer to my colour vision as my "search" mode (focused, intentional) and the peripheral part of my visual field as my "scan" mode (semi-subconscious, but surprisingly effective). Interestingly, many of my images start with something popping up at the edges of my perception. It's uncanny how once something is noticed, the head snaps into position and both eyes are used with all their abilities - most importantly, colour vision - to discern what's really there. But it all starts with a strong, though blurred and brief, b&w moment.
M.