Green Algae
- Cladophoraceae
- Cladophora
- columbiana (Green Ball)
- sericea (Graceful Green Hair)
- Rhizoclonium
- tortuosum (Twisted Sea Hair)
- Bryopsidaceae
- Derbesia
- marina (Green Sea Felt)
- Codiaceae
- Codium
- fragile (Sea Staghorn) (PC)
- ritteri (Coarse Spongy Cushion)
- setchellii (Smooth Spongy Cushion)
- Prasiolaceae
- Prasiola
- meridionalis (Emerald Carpet)
- Acrosiphoniaceae
- Acrosiphonia
- arcta (Arctic Sea Moss)
- mertensii (Green Rope) (PC)
- Kornmanniaceae
- Blidingia
- minima (Dwarf Sea Hair)
- Kornmannia
- leptoderma (Seagrass cellophane)
- Monostromataceae
- Monostroma
- grevillei (Sea Cellophane)
- Ulotrichaceae
- Ulothrix
- flacca (Mermaid's Tresses)
- Ulvaceae
- Enteromorpha
- intestinalis (Sea Hair)
- linza (Green String Lettuce)
- prolifera (Branched String Lettuce)
- Ulva
- fenestrata (Sea Lettuce)
- Ulvaria
- obscura (Dark Sea Lettuce)
Brown Algae
- Chordariaceae
- Chordaria
- flagelliformis (Chocolate Pencils)
- Eudesme
- virescens (Gooey Golden Seaweed)
- Coilodesmaceae
- Coilodesme
- bulligera (Sea Chip)
- Phaeostrophion
- irregulare (Sand-scoured False Kelp)
- Dictyosiphonaceae
- Dictyosiphon
- foeniculaceus (Golden sea Hair)
- Ectocarpaceae
- Pilayella
- littoralis (Sea Felt)
- Leathesiaceae
- Leathesia
- difformis (Sea Cauliflower)
- Punctariaceae
- Melanosiphon
- intestinalis (Twisted Sea Tubes)
- Soranthera
- ulvoidea (Studded Sea Balloons)
- Scytosiphonaceae
- Colpomenia
- bullosa (Sea Rubber)
- peregrina (Bulb Seaweed)
- Petalonia
- fascia (False Kelp)
- Scytosiphon
- simplicissimus (Soda Straws)
- Heterochordariaceae
- Analipus
- japonicus (Bottlebrush Seaweed)
- Ralfsiaceae
- Ralfsia
- fungiformis (Sea Fungus)
- Sphacelariaceae
- Sphaecelaria
- rigidula (Brown Rock Fuzz)
- Dictyotaceae
- Dictyota
- binghamiae (Mermaid's Gloves)
- Desmarestiaceae
- Desmarestia
- aculeata (Witch's Hair)
- ligulata (Flattened Acid Kelp)
- munda (Coarse Acid Kelp)
- viridis (Stringy Acid Kelp)
- Alariaceae
- Alaria
- fistulosa (Dragon Kelp)
- marginata (Ribbon Kelp)
- nana (Small Ribbon Kelp)
- Lessoniopsis
- littoralis (Strap Kelp)
- Pterygophora
- californica (Woody-stemmed Kelp)
- Laminariaceae
- Agarum
- clathratum (Sieve Kelp)
- fimbriatum (Fringed Sieve Kelp)
- Costaria
- costata (Seersucker)
- Cymathere
- triplicata (Three-ribbed Kelp)
- Hedophyllum
- sessile (Sea Cabbage)
- Laminaria
- bongardiana (Split Kelp)
- saccharina (Sugar Kelp)
- setchellii (Southern Stiff-stiped Kelp)
- yezoensis (Suction-cup Kelp)
- Pleurophycus
- gardneri (Sea Spatula)
- Lessoniaceae
- Egregia
- menziesii (Feather Boa)
- Eisenia
- arborea (Double Pompom Kelp)
- Macrocystis
- integrifolia (Small Perennial Kelp)
- pyrifera (Giant Perennial Kelp)
- Nereocystis
- luetkeana (Bull Kelp)
- Postelsia
- palmaeformis (Sea Palm)
- Cystoseiraceae
- Cystoseira
- geminata (Northern Bladder Chain)
- Sargassaceae
- Sargassum
- muticum (Wireweed)
- Fucaceae
- Fucus
- gardneri (Rockweed)
- Pelvetiopsis
- limitata (Dwarf Rockweed)
Red Algae
- Erythrotrichiaceae
- Smithora
- naiadum (Seagrass Laver)
- Bangiaceae
- Bangia
- sp. (Black Sea-Hair)
- Porphyra
- abbottae (Black Seaweed)
- cuneiformis (Red Cellophane)
- fucicola (Rockweed Laver)
- kurogii (Kurogi's Laver)
- nereocystis (Bull-kelp Laver)
- perforata (Purple Laver)
- pseudolinearis (Long Laver)
- torta (Teal Nori)
- Palmariaceae
- Halosaccion
- glandiforme (Sea Sac)
- Palmaria
- callophylloides (Frilly Red Ribbon)
- hecatensis (Stiff Red Ribbon)
- mollis (Red Ribbon)
- Ahnfeltiaceae
- Ahnfeltia
- fastigiata (Bushy Ahnfelt's Seaweed)
- Gracilariaceae
- Gracilaria
- pacifica (California Limu)
- Gracilariopsis
- sjoestedtii (Sea Spaghetti)
- Hildenbrandiaceae
- Hildenbrandia
- rubra (Rusty Rock)
- Corallinaceae
- Bossiella
- californica (California Coral Leaf)
- cretacea (Chalky Coral Seaweed)
- orbigniana (Winged Coral Seaweed) (PC)
- Corallina
- officinalis (Common Coral Seaweed) (PC)
- frondescens (PC)
- vancouveriensis (Graceful Coral Seaweed)
- Leptophytum
- adeyi
- Lithothamnion
- phymatodeum (Rock Crust)
- Lithophyllum
- impressum
- Melobesia
- marginata
- mediocris (Seagrass Crust)
- Mesophyllum
- lamellatum (Coralline Crust)
- vancouveriense (Kelp Crust)
- Pseudolithophyllum
- muricatum
- neofarlowii
- whidbeyense
- serraticardia
- macmillanii (Macmillan's Coral Seaweed)
- Galaxauraceae
- Scinaia
- confusa (Red Antlers)
- Liagoraceae
- Nemalion
- helminthoides (Rubber Threads)
- Dumontiaceae
- Constantinea
- rosa-marina (Cup and Saucer)
- subulifera (Cracked Saucer)
- Cryptosiphonia
- woodii (Bleached Brunette)
- Dilsea
- californica (California Red Blade)
- Dumontia
- contorta (Purple Pencils)
- Farlowia
- mollis (Farlow's Seaweed)
- Neodilsea
- borealis (Northern Red Blade)
- natashae (Natasha's Red Blade)
- Endocladiaceae
- Endocladia
- muricata (Sea Moss)
- Gloiopeltis
- furcata (Jelly Moss) (PC)
- Gigartinaceae
- Chondracanthus
- exasperatus (Turkish Towel)
- Mazzaella
- cornucopiae (Iridescent Horn-of-Plenty)
- heterocarpa (Northern Mazza Weed)
- splendens (Splendid Iridescent Seaweed)
- Kallymeniaceae
- Callophyllis
- violacea (Violet Sea Fan)
- Erythorphyllum
- delesserioides (Red Sea-leaf)
- Euthora
- cristata (Delicate Northern Sea Fan)
- Phyllophoraceae
- Ahnfeltiopsis
- gigartinoides (Loose Ahnfelt's Seaweed)
- Mastocarpus
- papillatus (Turkish Washcloth, Tar Spot)
- Furcellariaceae
- Opuntiella
- californica (Red Opuntia)
- Turnerella
- mertensiana (Red Sea-cabbage)
- Halymeniaceae
- Prionitis
- lanceolata (Bleachweed)
- Plocamiaceae
- Plocamium
- cartilagineum (Sea Comb)
- tenue? (PC not in NPS)
- Champiaceae
- Gastroclonium
- subarticulatum (Sea Belly)
- Faucheaceae
- Fauchea
- laciniata (Blue Branching Seaweed)
- Lomentariaceae
- Lomentaria
- hakodatensis (Hakodate Sea Tangle)
- Rhodymeniaceae
- Sparlingia
- pertusa (Red Eyelet Silk)
- Ceramiaceae
- Antithamnion
- defectum (Dwarf Skein)
- Antithmnionella
- pacifica (Hooked Skein)
- Callithamnion
- pikeanum (Beauty Bush)
- Ceramium
- pacificum (Staghorn Felt)
- Microcladia
- borealis (Coarse Sea Lace)
- Neoptilota
- asplenioides (Sea Fern)
- Pleonosporium
- vancouverianum (Alternate Skein)
- Ptilota
- filicina (Red Wing)
- Scagelia
- occidentale (Scagel's Skein)
- Delesseriaceae
- Cryptopleura
- ruprechtiana (Hidden Rib)
- Delesseria
- decipiens (Winged Rib)
- Membranoptera
- beringiana (Bering Membrane Wing)
- Phycodrys
- riggii (Common Sea Oak)
- Polyneura
- latissima (Crisscross Network)
- Tokidadendron
- kurilensis (Northern Sea Oak)
- Rhodomelaceae
- Neorhodomela
- larix (Black Pine)
- oregona (Oregon Pine)
- Odonthalia
- floccosa (Sea Brush)
- sp. (Rockweed Brush)
- Osmundea
- spectabilis (Sea Laurel)
- Polysiphonia
- hendryi (Polly Hendry)
- pacifica (Polly Pacific)
- Pterosiphonia
- bipinnata (Black Tassel) (PC)