Did you know that kelp don’t have roots? They use branching, root-like, gnarled structures called holdfasts to anchor themselves to rocks. Holdfasts don’t carry nutrients or water – they are only for securing the kelp to a rock where it will grow.
Here is a photo of a (yellowish) holdfast that we saw recently on a dive with our modified BlueROV2:
![](http://www.undersearov.com/wp-content/uploads/2021/09/Kelp-Holdfast-aug21.png)