Apocynaceae: Dogbane Family

Spreading / Bitter Dogbane – Apocynum androsaemifolium

Blooms:

Mar–Oct

Plant Height:

16–30 cm

Flower Size:

Small

Origin:

Native

Habitat:

Dry flats & rocky slopes above 1000 m

Notes:

This is a low-growing plant, with stems diffusely branched, and milky sap.  The drooping leaves have smooth margins, shaped as pointed ovals.  The flowers are in small terminal clusters, pink or whitish with pink stripes, and 5 stamens.  Pedicels are 4 mm long, and the bell-shaped corolla with its noticeably recurved lobes is 3 x as long as the calyx.  The plant is poisonous.

Indian Milkweed – Asclepias eriocarpa

Blooms:

May–Oct

Plant Height:

40–80  cm

Flower Size:

Large cluster

Origin:

Native

Habitat:

Dry, barren places

Notes:

This toxic plant has distinctive pale gray, felty leaves, and long stems with dense clusters of small flowers.  The flowers are usually pink, but may be white or purplish.  They  have distinctive reflexed petals, and 5 hood-like appendages, each with a small projecting horn at the top.  The fruit is large and greenish-yellow.  Leaves are opposite, or whorled in 3s or 4s.  Milkweeds are a favored food source for Monarch Butterflies.

Narrow-leaved Milkweed – Asclepias fascicularis

Blooms:

May–Oct

Plant Height:

40–80 cm

Flower Size:

Large cluster

Origin:

Native

Habitat:

Dry ground in valleys & foothills

Notes:

Flowers are similar to those of Indian Milkweed (Asclepias eriocarpa, see above).  However, these appendages are more cup-shaped than hooded, and the horn is strongly exserted.  Petals are green-white with a purplish tinge. Leaves are narrow, glabrous and opposite or whorled in 3s or 5s.  There are often smaller leaves in the axils.  Fruits are erect, long and narrow.

Greater Periwinkle – Vinca major

Blooms:

May–June (Jan)

Stems:

Trailing

Flower Size:

Medium

Origin:

Europe

Invasive?

Yes – Moderate

Habitat:

Generally sheltered places

Notes:

This garden escapee has distinctive bluish-purple flowers, and a sprawling growth habit.  The arching stems often root at the tips.  It spreads very aggressively.