Hügelbeet effect after 5000 years

We're experiencing a huge drought in Europe, fields turn brown even in places like Ireland.
This has led to some interesting sightings that otherwise wouldn't be there, and some archaeologists on the Emerald Isle, which isn't so emerald everywhere anymore, have made important discoveries.
Neolithic structures that were put up 5000 years ago can now be seen through patterns in the grass. The vegetation is greener at places where there's still some wood remaining in the ground after all that time.



Above picture is from this blog: https://blog.shadowsandstone.com/. I recommend reading it. The findings are of great archaeological importance and have been in the papers around the world.

I've often read in articles about Hügelbeets that they work over time, but I've missed the info that they still have an effect after 5000 years, while this is so interesting to know and see!  

Very cool! I read this article from the BBC about this same thing about a week ago. One of the things they mentioned was that foundations for structures were dug down into the clay, resulting in a deeper section of topsoil (that traps more water) where the foundation once stood. They've even got some cool images to illustrate it.

I read about this phenomenon, too. That is encouraging for those of us who have hugel beds.