Oyster seed is taken out of a winter storage pit in the early Spring.  The seed, after
being dormant all winter quickly grow a new edge.  The seed is either bought from a
hatchery, or captured from the wild spawn.  Wellfleet has one of the only naturally
occurring oyster spawns in the state.  
As the oyster seed grows it needs to be divided into mesh bags to create more space.  During
the summer months from (May-September) the oysters grow very rapidly, as much as an inch a
month.  The larger oysters are put into a larger mesh bag and onto elevated steel racks.  After
several weeks the bags are broken down again, and re-attached to the racks to grow for the
duration of the season.
Bags are laid out on top of the racks.  Wellfleet regulates that shellfish gear, including racks
cannot be any higher than 18" off the ground. Generally steel racks hold 5-6 oyster bags.   
Some racks are double layered and hold 10-12 bags.  Generally wire ties or stainless steel pins
are used to secure the bags to the racks.  Plastic pipes hold the tops of the oyster bags closed.
Thousands of oyster bags can be stored on a single aquaculture farm.   
After the oysters have grown to legal size (three inches)
they are graduated into grow-out cages, where they will
harden and firm their final edge before being harvested.  
These cages are made of thick metal wire that can
support they weight of many oysters.  Approximately 250
legal oysters can fit in one cage.
Oysters that are grown aquaculturally either come from a hatchery, where large
adult oysters are induced into spawning and the resulting spat is collected.  
These seedlings are then sold usually by the 100,000 count to licensed shellfish
grant holders.  The other way to obtain spat oysters is to catch them when the
oysters in the wild naturally spawn.  The oyster larva for a short period of time, will
actually be free swimming albeit at the control of the wind and tides.  It is at this
time they are "looking" for a suitable place to spend their life.  To catch the oyster
spat "chinese hats" are dipped in a slurry of concrete lime and sand.  This mixture
mimics the consistency of shells; the most often landing spot for a seed oyster.  
After the hats are dipped they are hammered into the ground to soak from July
until November.  Then they will be broken down; the seed collected.
click to see "chinese hat"
construction
click images to enlarge
click images to enlarge