Angiosperms: Dicotyledons

Scrophulariaceae
Figwort Family

• Notes: Penstemon digitalis is about the same height as P. grandiflorus, but the leaves are somewhat larger and narrower (5” by 3/4”). The inflorescence has flowers on axillary branches from the upper nodes. The flowers are similar, but the corolla is shorter (7/8”) with hairs on the outside. The calyx is shorter (3/16”). The fruits are similar but smaller (1/4” long). Flowering is from early to late June, and fruiting begins in mid-June. P. digitalis is frequent in moist, sandy soils on prairies and in other open places in southeastern Iowa, becoming very infrequent to the north and west.
• Bibliography from Biodiversity Heritage Library
• Vascular Plants of Iowa