April 19, 2016

Our 1 week follow up of the Nahant planting was done yesterday.

Observations

Of the 20 disks set last week, 8 were visible.  Most were buried or completely buried.

There was no shifting of the disks relative to the placement. ( they stayed where we put them )of the 8 visible,   4 had no viable eelgrass connected to them.  It is believed the rhizomes were washed away by wave action.

The other 4 had eelgrass attached and buried by current driven sand.  Of the completely buried disks   It was noted that many still had intact eelgrass.  (This through the eelgrass sticking up through the sand.   ( We had to verify this through gently tugging on the blades) -   there was other storm tossed weed / grass in the area - that one could just pick up.

Initial conclusions:

The disks all settled to the bottom in the correct orientation.   They seem to be easily buried by current.

We need to plant deeper - in water that even at low tide there is some amount of water above the disks.

We need to practice attaching the rhizome to the burlap better-   This should improve rhizome adherence once deployed.

We brought back one of the non-viable disks  it looks like a short duration in active ocean water began the initial stage of degradation.   Visually there seems to be some wearing along the top of the disk.  This is a good sign, as we have been thinking about degradation time in a real deployment.