Can you please show the settings of the greenery material on the beautiful picture with trees?
How did you make it shine so nicely with the sun on the background?
There is no secret in the materials or in the light.
I used only one corona sun with corona sky, and for materials of leaves only translucency. The trick to have variation is to use a texture in channel translucency.
The value of "Fraction" I was increasing until you reach the result I liked, this value varies according to the type of leaf.
i wonder if translucency can be a substitute for sub surface scattering
Yes you can, depending on your need you can use any of the 4 above combinations (Absorption, translucency, translucency+Absorption and translucency+Absorption+refraction with glossiness). As the final result depends on many factors, in each case you will need to do many tests until you reach the optimal setting.
Another example are these lego bricks, where I used a bit of translucency to achieve an effect of SSS:
http://forum.corona-renderer.com/index.php/topic,3218.0.html