Virginia Tech Weed Identification Guide

Prickly Sida or Teaweed: Sida spinosa

Weed Description:  A summer annual with yellow flowers and very small spines at the base of each leaf and branch. This weed is one of the ten most common and troublesome weeds in peanuts, cotton, and soybeans in most of the southern states.   Prickly sida is primarily a weed of agronomic crops, but can also be found in horticultural crops, landscapes, pastures, hay fields, and gardens. 

Seedlings: Both cotyledons are generally heart-shaped with a small indentation at the cotyledon apexes.   The cotyledons and the stems below the cotyledons (hypocotyls) are covered with short hairs.

Leaves:  Arranged alternately along the stem, approximately 3/4 to 2 inches long, and inconspicuously hairy.   Leaves are oval to lanceolate in outline with toothed margins.  Leaves occur on petioles that are 1/2 to 1 1/4 inches long and have small spines (stipules) that are 5 to 8 mm long at the base of each leaf petiole.

Stems:   Erect, branched, ranging from 8 to 20 inches in height.  Stems also have hairs.


Roots:  A taproot and a fibrous root system.

Flowers:  Occur singly or in clusters on flower stalks (peduncles) that arise from the area between the stems and leaf petioles.  Flowers consist of 5 yellow petals that are 4 to 6 mm long.

Identifying Characteristics:   The seedlings with 2 heart-shaped cotyledons, and the small spines that occur at the base of each leaf petiole are both features that help in the identification of prickly sida.  Velvetleaf (Abutilon thophrasti), Spurred Anoda (Anoda cristata), and Arrowleaf Sida (Sida rhombifolia) seedlings are very similar to those of prickly sida.  However, prickly and arrowleaf sida have 2 heart-shaped cotyledons unlike the round and heart-shaped cotyledons of velvetleaf.  Spurred anoda also has two heart-shaped cotyledons like prickly and arrowleaf sida, however the first true leaf of spurred anoda is not as coarsely toothed as that of prickly or arrowleaf sida.  The cotyledons of arrowleaf sida are essentially identical to those of prickly sida, however the first true leaf of arrowleaf sida is rhombic in outline and tapers to the base unlike the first true leaf of prickly sida.