Tuesday, 27 September 2016

Seaweed Collecting

After having read so much about 19th century seaweed collecting, and examining the two seaweed books first hand, I thought it was about time I started my own seaweed collection, just so I could experience working with the material itself and also the technique of seaweed pressing. This may be easy if you live by the sea, but in Canberra it's at least a couple of hours journey to a beach! Luckily I was given several bags of seaweed from two different locations by friends and family who spent a weekend at the north and south coasts respectively, and who took time out to gather a variety seaweeds that had been washed up by the tide.  Each state has rules regarding the quantity of seaweed that can be collected off its beaches, so it is advisable to check these limitations before you start collecting.
There are a variety of instructions available on how to press seaweed over the internet but basically the seaweed is 'floated' onto a sheet of watercolour, or other heavy gsm paper, and then further arranged using a paintbrush and tweezers. This is important for seaweeds that have feathery fronds, so that they do not clump together when pressed.
Seaweed floated onto paper before arranging.
Sometimes it is necessary to trim the seaweed so that the fronds at the back do not create too much bulk for pressing. This could lead to uneven drying of the specimen and possible mould if not pressed properly.

A few of the seaweeds found on MacMasters beach, NSW

It is important to ensure that the papers separating the pressed seaweeds are changed regularly and that the stacks are aired to avoid drying issues.

As mentioned in earlier posts, some seaweeds will adhere directly to the paper under pressure, however others will dry and come away from the mount.  In this case it is usual to use herbarium mounting tape to ensure that the specimen remains fast.  Specimens were also stitched to the mounting papers with a fine linen thread in past herbarium samples.

I expected the process of sorting through a few bags of seaweeds to take me an hour or so, but to my surprise the more I looked, the more varieties of seaweed I found.  I think I ended up pressing over 40 specimens that day, no two of which looked the same. The challenge would be to now identify them, and I guess this puts me firmly in the same category as those anonymous 19th century women strolling along the beach, observing and collecting then becoming entranced with the beauty to be found washed up with the tide, and wanting to find out more about them.

1 comment:

  1. How lovely!
    These sea weeds are so beautiful aren't they? I can understand your passion with collecting them. x