Creating Trenches in UE4 landscape?


Quick question for you all.

Like most of you I’m making the transition from UDK to UE4, and there’s a lot of new tools to learn.
One of them is the new landscapes, and I’m stuck on figuring out how to create trenches.
Making them for Red Orchestra and UE3 was as simple as increasing the tessellation and changing the visibility on a quad of the landscape.

I can remove big areas just fine with add/remove, and even the visibility tool seems to work fine, but it’s still too big for what I’d like.

Is there any specific tutorial on how to make trenches in UE4, or any hints you guys might be able to throw my way to help me out?
Possibly something related to increasing the tessellation of the landscape?

Found everything I needed here:

And also,

Have you tried importing a custom height-map with the trenches already defined? Looking on***Google*** I found some interesting ones, which need to be saved in the correct format, or with a ***height-map generator ***](height map generator - Bing images)