I followed the instructions a little more carefully this time:

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Not sure exactly what I did wrong the last time, it wasn't the obvious.

The channel mask was off, think I forgot to delete in 1e, Step 2.

In any case, thanks for all your helpful suggestions and I will know better next time.

Some nice suggestions in the various follow-ups:

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I would add that for 5b in Step 1, when you are using the Threshold tool, the black
lines should be thicker than you might like, as the Drop Shadows will intrude quite a
bit into these interior forest streamlets and whatnot.

I really like the tree patterns, I updated the comments so that the pattern name
shows up correctly in the Clone Tool window (unzip the attached into your 'Patterns'
folder, the sub-folders are fine but not necessary I think).

Trees with Comments.zip

I really like these tree patterns for higher elevation trees (i.e. above the forest level
but below the treeline). You can clone them in as lightly or heavily as you like.

Anyhow, thanks again everyone.