roses

genus Rosa

Member of rose tribe (tribe Roseae)
rose family (family Rosaceae)
dicots (class Magnoliopsida)
flowering plants (subphylum Angiospermae)

Except for extremely rare examples that I don't expect to encounter, there are no other wild species of this genus in the bay area.

Key features:

prickles slender or thick-based
size of shrub
sepals with lateral lobes or not, glands or not
length of petals

slender prickles

baldhip rose
Rosa gymnocarpa

baldhip rose
Rosa gymnocarpa

loose shrub
prickles 2–8 mm, ± slender, straight [example]
leaf axis generally glabrous
leaflets glabrous
sepals glandular or not, entire
petals ± 10 mm, pink to red
very common in the bay area

ground rose
Rosa spithamea

ground rose
Rosa spithamea

dwarf shrub, generally < 50 cm
prickles 3–8(12) mm, generally slender (thick-based), ± straight [example]
leaf axis generally glabrous (finely hairy), glandular
leaflets 5–7(9), (±) glabrous
sepals generally glandular, entire
petals 10–15 mm, pink to red
common in the bay area

thick-based prickles

california wild rose
Rosa californica

california wild rose
Rosa californica

shrub or thicket-forming, 80 cm – 2.5 m
prickles 3–15 mm, thick-based and compressed, generally curved [example]
leaf axis ± shaggy-hairy (± glabrous), hairs to 1 mm, glandless or glandular
leaflets 5–7(9), ± hairy, sometimes glandular
sepals entire, glandular or not
petals generally 15–25 mm, pink
very common in the bay area
hosts rose galls

dog-rose
Rosa canina

dog-rose
Rosa canina

shrub or thicket-forming, generally 80 cm – 4 m
prickles ± few, 3–10 mm, thick-based and compressed, curved
leaf axis glabrous or with hairs to 1 mm, glandless
leaflets generally 5–7, (±) glabrous
sepals ± glandless, with toothed lateral lobes
rare
Nisene Marks, Marin, and Mt. Tam.

sweet-brier
Rosa rubiginosa

sweet-brier
Rosa rubiginosa

shrub or thicket-forming, 80 cm – 3 m
prickles ± 5–15 mm, thick-based and compressed, curved
leaf axis ± hairy, hairs 0.2–1 mm, glandular
leaflets generally 5–7, ± hairy, glandular
sepals glandular, with toothed lateral lobes
La Honda Creek OSP

iNaturalist may suggest woods’ rose (Rosa woodsii), but it’s not really in the bay area.

Toxicity:
except for thorns of rose (Rosa spp.):

0 – Non-toxic.

rose hips of rosehips, hip berries (Rosa spp.):

0 – Non-toxic.

4 observed taxons / 1 unobserved taxon / 1 key

Chris’s observations: 95 (48 are research grade)

Locations:

Months:

Jan.: 2
Feb.: 2
Mar.: 3
Apr.: 5
May: 18
Jun.: 18
Jul.: 11
Aug.: 10
Sep.: 12
Oct.: 7
Nov.: 5
Dec.: 2

For more details, use advanced search.

Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora