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Nuttallanthus texanus - Texas toadflax

Scientific Family
Scrophulariaceae
Synonyms
Linaria canadensis var. texana, L. texana
Other common names
blue toadflax
Plant type
Forbs and Subshrubs
Origin
Native
Lifecycle
Biennial or annual
Similar species
Linaria vulgaris, L. dalmatica
Height
Up to 32 inches
Riparian
Yes
Slender, erect plant with 1 to several branches tufted from the base; stems and leaves without hairs, dark green; flowers about 1/2 inch wide by 1 inch deep with spur.
An erect annual or biennial with dense dark green basal leaves compared to stem leaves; leaves and stems without hairs; spike-like clusters of purple, blue or white, 2-lipped flowers with long nectar spurs coming out the backsides.

Habitat

Found on arroyos, stream banks, grassy hillsides or in open chaparral in sand or gravel.
Plant Community
Riparian
Interior Chaparral
Grasslands
Desert Scrub
Low elevation
1500
High elevation
5000

Flower Characteristics

On slender, 2 to 12-inch unbranched spikes, flowers mature from bottom up. Spikes on 2 to 6 inch stems branch out from base, each with 2-lobed upper lip, 3-lobed lower lip with a long, slender, rear-projecting, down-curved spur behind the flower.
Flower color
Purple, blue or white
Flower shape
Irregular
Tubular
Yes
First bloom month
March
Last bloom month
June
Flower clusters
Elongated

Leaf and Stem Characteristics

Dense, hairless, dark green basal leaves, may be whorled; flower stems have blade-like leaves that branch out from the base of the plant.
Leaf type
Simple
Leaf color
Dark green
Leaf shape
Narrow
Leaf margin
Smooth
Leaf attachment
Basal
Alternate & Opposite
Leaves clasp
No
Leaf hairs
None
Spines
No

Fruit and Seed Characteristics

Capsule is thin-walled, spherical to almost cylindrical 1/16 to 1/4 inch long, irregularly opens to disperse many seeds when ripe.
Fruit type
Capsule
Fruit color
Light brown
Brown seeds are prism-like with 4 to 7 rounded angles and are slightly bumpy.