Sowthistle

Season: Winter Annual.

Stems: Smooth green or purple.

Leaves: Prickly edges.

Flowers: Small yellow.

Spanishneedles

Season: Summer Annual.

Stems: Erect, smooth and purple.

Leaves: Divided and in pairs at the stem.

Flowers: Yellow center with white petals.

Seeds: Long, narrow dark brown or black.

Spiny Amaranth

Season: Summer annual.

Stems: Smooth and reddish and grows 3 to 6 feet tall.

Leaves: Dark green.

Flowers: Small and grow in dense spikes.

Seeds: Black and shiny.

Spotted Spurge

Season: Summer Annual.

Stems: Erect, smooth, red and milky juice.

Leaves: Oblong with purple spots near base.

Flowers: Greenish clusters.

Seeds: 3 sided pod.

Swinecress

Season: Winter Annual

Stems: Prostrate and hairy.

Leaves: Deeply cut and re-cut.

Flowers: Tiny white flowers.

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