| Common Names |
Rockweed
|
| Family |
Fucaceae
|
| Elevations |
Upper to Middle Intertidal
|
| Distribution |
Alaska to Mexico
|
| Community |
Marine intertidal communities.
|
| Substrate |
Bedrock and other hard substrates
|
| pH |
|
| Shade |
Does not do well in the shade.
|
| Moisture |
Plant is used to extreme desication.
|
| Reproduction |
The tips of mature individuals swell up and provide flotation for the plant as well as reproductive chambers for developing sperm and eggs. During low tide, the swollen tips dry up squeezing out sperm and eggs which unite into a zygote during the next flood tide and settle onto a substratum.
|
| Size |
Individuals grow to 40-50 cm. The flattened dichotomously branching body has a prominent midrib running up the center of the branches. Healthy branches are ~ 15 mm wide.
|
| Attachment |
Holdfast
|
| Duration |
Can live up to 4 years.
|
| Growth Habitat |
|
| Wave-Exposure |
Low or High
|
| Habitat Significance |
Significant spawning habitat for herring. Significant fish habitat.
|
| Mistaken Identity |
A closely related species, Fucus spiralis may occur in the same area as F. gardneri but tends to grow a bit higher in the intertidal. Its blades tend to twist especially when dried out. Another distinction is the presence of tufts of hairs growing in pits on the surface of the blades of F. spiralis.
In the past Fucus gardneri was referred to as Fucus distichus. The 2006 seaweed key for our area suggests that the name may revert back to F. distichus in the near future.
|
| Other Use |
Native Americans historically harvested the dried swollen tips of Fucus - sometimes referred to as “Indian pop corn”.
|
| Cost |
N/A. Rockweed becomes readily established given the correct substrate and elevation.
|
