Below is the standard conversion using the Photoshop Channel Mixer. This sets a balance between red, green, blue of +40,+40,+20 respectively. Here the red leafed tree is almost lost in the conversion, as is the foreground, leaving a rather bland conversion.
So the first thing is to bring out the reds by boosting the red channel to +106. To counteract this the green channel has been reduced to -83 and the blue channel boosted to +81. This has brought out the reds, and darkened the greens. The effect of the blue slider has helped to brighten up the image and retain a neutral sky tone. Overall this has made an image with good contrasting tones.
The opposite effect has been achieved by reducing the reds to -16, darkening the tress and foreground, the green slider was boosted to +188 which has lightened the grass and green foliage.This has however merged the red leaf tree and the background tree into an indistinguishable lump. Finally the blue slider was reduced to -3 to compensate for the boost in green and to retain that overall sky tone.
Again I think that this was worked well, but with the loss of the reds, it makes a less interesting image.