Asteraceae : Machaeranthera pinnatifida
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Family Name
Asteraceae
Common Name
Lacy Tansyaster, Spiny Goldenaster,Cutleaf ironplant
Description
Machaeranthera pinnatifida is an evergreen, perennial herb usually with numerous, ascending to erect stems, branched above, reaching 5-40 cm in height, with at least the upper 1/3 covered with minutely glandular and short wooly hairs. The simple alternate leaves are oblong to linear subspatulate, 1–6 cm long and 2-10 mm wide, toothed with bristle-tipped teeth or deeply pinnate lobes that are linear and spine-tipped. Inflorescence is a flat-topped cluster of heads, each solitary on a branch tip. Heads are radiate with a hemispheric involucre 6–9 mm long with 5 or 6 series of bracts that are hairy and sticky to the touch, the outer ones green and the inner ones whitish. There are 14 to 60, yellow ray flowers with ligules 4–10 mm long, and 30 to 150 disk flowers with yellow corollas 4–6 mm long. Achenes are about 2 mm long. Spiny goldaster blooms from May through September on open prairies and plains throughout South Dakota.
Horticulture Notes
Seed Collection: Collect seed in July- September from fluffy seedheads.
Germination: Germinates at 70° F in the greenhouse for planting out in the spring. Can be fall seeded.
Soils: Well-drained sandy or gravelly soil preferred, but can grow in heavier soils.
Light: Full sun
Water :Dry
Additional Notes
Lacy Tansyaster is one of many short to medium tall yellow flowered composites. It attracts butterflies and bees. This species grows well in a native plant garden and has flowers and seedheads for a sustained period, but is not especially showy.