less trees

[spenser]

"And there were far less trees."

May I know why the author of the above sentence used "less" instead of "fewer" before a countable noun?

[Tdol]

Many native English speakers use less + plural countable. Formally, fewer is preferred, but it depends on things like regions.

[redcrows]

I think trees can be countable or uncountable.
ten trees
the trees = the forest

[Tdol]

It doesn't matter whether you can count them; countab ility is theoretical. We would find it hard to count the stars, but that doesn't make them grammatically uncountable.