31320 is a Postal Code in Liberty County.
31320 a.k.a. Navarretia squarrosa is a spreading annual plant from North America which is noted for its skunk-like odour. It grows to between 10 and 60 cm in height and has tubular lilac pink to deep blue flowers up to 12 mm in diameter in dense terminal heads, encircled by a spiny sepals and bracts. The leaves are pinnately lobed and spiny.