Thin Petal Larkspur
Delphinium lineapetalum
General: Perennial from somewhat fleshy and tuberous roots, the stems 1.5-4 dm. tall, usually single and simple.
Leaves: Leaves few, long-petiolate, mostly basal, the blades 2-6 cm. broad, 2-4 times parted or lobed into linear or oblong-lanceolate segments 1.5-5 mm. broad; cauline leaves much reduced upward.
Flowers: Inflorescence simple or compound, the racemes 3-15 flowered; the lower pedicels several times as long as the flowers, spreading or ascending; sepals 5, pale blue, widely spreading, 17-25 mm. long, the lower pair the largest; the spur 13-20 mm. long, from about as long to twice as long as the top sepal; petals 4, pale blue to white, very prominently lined with purplish-black, the blade small, shorter than the claw; stamens numerous; pistils 3.
Fruits: Follicles 15-22 mm. long, somewhat spreading.
Leaves: Leaves few, long-petiolate, mostly basal, the blades 2-6 cm. broad, 2-4 times parted or lobed into linear or oblong-lanceolate segments 1.5-5 mm. broad; cauline leaves much reduced upward.
Flowers: Inflorescence simple or compound, the racemes 3-15 flowered; the lower pedicels several times as long as the flowers, spreading or ascending; sepals 5, pale blue, widely spreading, 17-25 mm. long, the lower pair the largest; the spur 13-20 mm. long, from about as long to twice as long as the top sepal; petals 4, pale blue to white, very prominently lined with purplish-black, the blade small, shorter than the claw; stamens numerous; pistils 3.
Fruits: Follicles 15-22 mm. long, somewhat spreading.