Rosaceae: Rose Family — Strawberry, Blackberry & Thimbleberry

Plants in the Rose family include many of our best-loved ornamentals and fruits.  The flowers usually have 5 petals, 5 sepals and numerous stamens, attached to a saucer- or bowl-shaped hypanthium.  Often the oval leaves are toothed, and there is a stipule at the petiole base.

Beach Strawberry – Fragaria chiloensis

Blooms:

Feb–Nov

Plant Height:

stems 5 – 20 cm

Flower Size:

Medium

Origin:

Native

Habitat:

Coastal grasslands and lower dunes

Notes:

Similar to Wood Strawberry, but with larger flowers and fruits.  Petals are white or pinkish, 10-18 mm, much longer than sepals.  Leaves are thick and leathery, dark green above with prominent veins, and densely hairy underneath.  Leaf edges are often curled under.  Stems are hairy.  This plant spreads by reddish horizontal runners (see far right image).  Fruits 1-2 cm.  This species is often dioecious, and may be used as groundcover in coastal areas.  Photos by Cliff Halverson.

Fragaria chiloensis
Fragaria chiloensis
Fragaria chiloensis
Fragaria chiloensis

Wood Strawberry – Fragaria vesca

Blooms:

Jan–July

Plant Height:

3–15 cm

Flower Size:

Medium

Origin:

Native

Habitat:

Shaded, moist places

Notes:

This plant needs little comment other than to say that the fruits make up in flavor for what they lack in size. The leaves are divided into 3 thin leaflets. The flowers are pure white or occasionally pink-tinged.

Himalayan Blackberry – Rubus armeniacus

Blooms:

Mar–June

Plant Height:

Stems < 3 m

Flower Size:

Medium

Origin:

Eurasia

Invasive?

Yes – high

Habitat:

Woods and damp places, disturbed areas

Notes:

This is similar in appearance and habit to Calilfornia Blackberry (Rubus ursinus).  But it has much fatter stems (pentagonal in cross-section rather than round), and leaves which are white-tomentose beneath.  The stem shape is clearly visible, especially on larger stems.  Leaves are also slightly different in shape, more obovate than spade-shaped.  Prickles are stout, straight or curved, with a broad base.

Thimbleberry – Rubus parviflorus

Blooms:

Mar–Aug

Plant Height:

1–2 m

Flower Size:

Large

Origin:

Native

Habitat:

Shaded places, especially near water

Notes:

This common shrub has an odd scientific name, since “parviflorus” means small-flowered, yet its flowers are larger than any of the other members of its genus found in California.  Its large pure white flowers have petals that are 14–22 mm long.  The stems have no prickles.  The leaves are large, soft and palmately-lobed. The delicious fruit is like a rather flat raspberry.  The fruits of this genus are divided into “blackberry-type” (the receptacle comes away with the fruit when it is picked) and “raspberry-type” (the fruit separates easily from the receptacle when picked).  The difference is immediately apparent, even in store-bought fruit.

California Blackberry – Rubus ursinus

Blooms:

Mar–July

Plant Height:

Stems < 2 m

Flower Size:

Medium

Origin:

Native

Habitat:

Woods and damp places, disturbed areas

Notes:

A very common, aggressively rambling shrub, with round prickly stems.  The plant is generally dioecious, male flowers (first photo on left) and female flowers (second photo) are borne on separate plants.  The flowers typically have 5 petals, but multiple-petaled forms are occasionally found.  Leaves are simple or compound, in 3s, rough and coarse-toothed.  Fruits are edible (from female bushes only — for obvious reasons).  The fruits of this genus are divided into “blackberry-type” (the receptacle comes away with the fruit when it is picked) and “raspberry-type” (the fruit separates easily from the receptacle when picked). The difference is immediately apparent, even in store-bought fruit.