Those are awsome!
Are they mounted on pennies? They look kinda delicate. 
I like the rope, but don't know why they would do that... who can understand their primitive brains, anyways?
And yer gardener, there, looks wonderful, too!

A handful of coins, cocktail stick/bamboo skewer/balsa, thick thread & GW/Foundry skulls

Superglue lengths of stick to the coins. PVA base & add gravel & sand. Wind thread around pole & glue in position

Undercoat, basecoat, dry-brush, add skull, add static grass.
Pretty simple & quick to build. They wont take really rough handling but are robust enough in general.