Family Description:
Four or more cells of the same height as the axial cell are cut off the various faces of the axial cell; these are called pericentral cells. Tetrasporangia are tetrahedrally divided. Each cystocarp is surrounded by a well-developed pericarp.

Species description:
Black Pine is a perennial alga that often forms extensive mats mostly in the low intertidal. Axes are clumped, and main axes are either unbranched or branch very few times and reach a height of 10 to 20 cm (4 to 8 in) or more. Numerous coarse side branchlets are crowded along the main axis, and they characteristically look rather clumped. These side branchlets are rather stiff, are all approximately the same length (up to about 1 cm or less than 0.5 in) and come off all around the supporting axis like a bottle brush. The whole organism is brownish black in color, but towards the end of the growing season it can begin to lose color in a patchy and irregular manner.


This species has an isomorphic life cycle; that is, the gametophytic individuals are indistinguishable from the tetrasporophytes. Also, the gametophytes are dioecious (male and female individuals are separate).

Individuals collected from southern British Columbia/northern Washington were able to withstand a week of immersion in water at a temperature of 25°C (77°F) but died when placed in warmer water.
In central Oregon, it grows most rapidly in spring and summer, sometimes growing as much as 1.2 mm per day. In one study, individuals growing higher in the intertidal zone had fewer, shorter branches than ones growing at lower levels.

Release of spores occurred year round in central Oregon except in January and February, when upright branches died back. Recruitment of young individuals of Black Pine onto freshly cleared rock was extremely slow, suggesting to the researchers that dense populations of this species are maintained by vegetative spreading from existing individuals and then long persistence of these. Research on the outer coast of Washington State showed that once the tough holdfasts of Black Pine were established, the alga could grow vegetatively and easily monopolize the rocky surface in a tidepool. Because Black Pine tolerates some sediment, it was a superior competitor to other algae that could not.

Black Pine is abundant in exposed situations such as along our outer coast.

Black Pine has moderate caloric value (3.41 Calories per gram of dry weight). It contains bromophenols, which can deter some herbivores.

Source:  North Pacific Seaweeds

Synonyms and Alternate Names:
Fucus larix
Rhodomela larix