Pr-Sc

Weeds: Prickly lettuce (China lettuce) – Lactuca serriola

Weeds: Prickly lettuce (China lettuce) – Lactuca serriola Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 04:41 Scientific name: Lactuca serriola Family: Asteraceae (Compositae) Cycle: Annual/Biennial Plant type: Broadleaf Prickly lettuce leaves Photo by: R. Parker Biology Prickly lettuce grows from one to five feet tall from a large taproot. The sap is milky. Seedling […]

Prickly lettuce leaves.

Weeds: Prostrate knotweed – Polygonum aviculare

Weeds: Prostrate knotweed – Polygonum aviculare Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 06:56 Scientific name: Polygonum aviculare Family: Polygonaceae Cycle: Annual Plant type: Broadleaf Prostrate knotweed leaves Photo by: R. Parker Biology Prostrate knotweed is a low-growing plant with wiry stems and a thin taproot. Plants branch extensively at the base, with branches […]

Prostrate knotweed leaves.

Weeds: Puncturevine (Tackweed, Goathead) – Tribulus terrestris

Weeds: Puncturevine (Tackweed, Goathead) – Tribulus terrestris Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 09:09 Scientific name: Tribulus terrestris Family: Zygophyllaceae Cycle: Annual Plant type: Broadleaf Puncturevine Photo by: R. Parker Biology Puncturevine is a prostrate plant growing from a taproot. Above ground, the branching, trailing stems grow one to six feet and are […]

Puncturevine against light blue background.

Weeds: Purple deadnettle (Red deadnettle) – Lamium purpureum

Weeds: Purple deadnettle (Red deadnettle) – Lamium purpureum Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 06:14 Scientific name: Lamium purpureum Family: Lamiaceae (Labiatae) Cycle: Annual Plant type: Broadleaf Purple deadnettle flowers Photo by: C.R. Foss Biology Purple deadnettle has the square stems and opposite leaves characteristic of most plants in the mint family. Plants […]

Purple deadnettle flowers.

Weeds: Purple loosestrife (Purple lythrum) – Lythrum salicaria

Weeds: Purple loosestrife (Purple lythrum) – Lythrum salicaria Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 06:20 Scientific name: Lythrum salicaria Family: Lythraceae Cycle: Perennial Plant type: Broadleaf Purple loosestrife in bloom Photo by: N.R. Ness Biology Purple loosestrife is an erect plant growing six to eight feet tall from a woody, rhizomatous root system. […]

Purple loosestrife in bloom.

Weeds: Purslane, common – Portulaca oleracea

Weeds: Purslane, common – Portulaca oleracea Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 07:05 Scientific name: Portulaca oleracea Family: Portulacaceae Cycle: Annual Plant type: Broadleaf Common purslane succulent leaves and flower Photo by: D.G. Swan Biology Common purslane reproduces by seeds, but it can also root from the stems or stem fragments which contact […]

Common purslane succulent leaves and flower.

Weeds: Quackgrass – Elymus repens (Elytrigia repens, Agropyron repens)

Weeds: Quackgrass – Elymus repens (Elytrigia repens, Agropyron repens) Categories: Grasses Pr-Sc Weeds Last review date: 2026-06-07 10:15 Scientific name: Elymus repens (Elytrigia repens, Agropyron repens) Family: Poaceae (Graminae) Cycle: Perennial Plant type: Grass Quackgrass Photo by: D.G. Swan Biology Quackgrass is a perennial grass which spreads by both seeds and rhizomes, forming dense clumps […]

Ground level view of Quackgrass.

Weeds: Red sorrel (Sheep sorrel) – Rumex acetosella

Weeds: Red sorrel (Sheep sorrel) – Rumex acetosella Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 07:13 Scientific name: Rumex acetosella Family: Polygonaceae Cycle: Perennial Plant type: Broadleaf Red sorrel leaves Photo by: T.W. Miller Biology Red sorrel has a creeping root system and spreads aggressively by underground roots and rhizomes. The upright, somewhat woody […]

Red sorrel leaves.

Weeds: Redroot pigweed (Rough pigweed) – Amaranthus retroflexus

Weeds: Redroot pigweed (Rough pigweed) – Amaranthus retroflexus Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 02:34 Scientific name: Amaranthus retroflexus Family: Amaranthaceae Cycle: Annual Plant type: Broadleaf Redroot pigweed Photo by: D.G. Swan Biology Redroot pigweed is a course, erect plant, growing two to three feet tall. The lower stems and branches and the […]

Redroot pigweed.

Weeds: Redstem filaree (Stork’s bill, Crane’s bill) – Erodium cicutarium

Weeds: Redstem filaree (Stork’s bill, Crane’s bill) – Erodium cicutarium Categories: Broadleaf Pr-Sc Weeds Last review date: 2026-06-07 04:15 Scientific name: Erodium cicutarium Family: Geraniaceae Cycle: Annual Plant type: Broadleaf Redstem filaree fruit and flowers Photo by: R. Parker Biology Redstem filaree is typically a winter annual (sometimes a biennial) growing from a rosette. The […]

Redstem filaree fruit and flowers.