Evergreen forest versus deciduous forest

I am interested in that process as it relates to evergreen trees. Could you compare the transpiration of moisture and soil building qualities, etc? In Southwest Montana in a monoculture of Douglas Fir and have a hard time picturing this forest as the climax of succession. Could this forest at one time have been filled with many species of trees? Could this forest ever return to that state?

Any idea?

Please help.

Thanks!

I didn't find the right solution from the Internet.

References permies.com/t/12135/Evergreen-forest-deciduous-forest

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