Weeds: Annual bluegrass – Poa annua categories: A-B Weeds last review date: 2025-12-15 02:18 Family: Poaceae (Graminae) Cycle: Annual/Perennial Plant type: Grass Annual bluegrass Photo by: T. Miller Biology Annual bluegrass leaves are folded in the bud and have a distinct midvein. The leaves are about 1⁄8 inch wide and cupped at the tip like […]
Weeds: Barnyardgrass – Echinochloa crus-galli categories: A-B Weeds last review date: 2025-10-13 09:43 Family: Poaceae (Graminae) Cycle: Summer annual Plant type: Grass Barnyardgrass Photo by: J.A. Kropf Biology Barnyardgrass grows in clumps up to five feet tall. Leaf blades are smooth, flat, and broad (about 1⁄2 inch or more) with a pointed tip. The leaf […]
Weeds: Bentgrass, creeping – Agrostis stolonifera categories: A-B Weeds last review date: 2025-10-13 09:48 Family: Poaceae (Graminae) Cycle: Perennial Plant type: Grass Creeping bentgrass Photo by: B.M. Johnson Biology Creeping bentgrass is a low-growing, perennial grass. Unmowed plants can reach 8 to 20 inches in height. The leafy stolons lie along the ground, rooting in […]
Weeds: Bermudagrass – Cynodon dactylon categories: A-B Weeds last review date: 2025-10-13 09:50 Family: Poaceae (Graminae) Cycle: Perennial Plant type: Grass Bermudagrass blades Photo by: D.G. Swan Biology Bermudagrass is a warm-season perennial grass that typically is prostrate and spreads to form dense patches. Spread occurs by both rhizomes and aboveground stems which root at […]
Weeds: Birdfoot Trefoil – Lotus corniculatus categories: A-B Weeds last review date: 2025-10-13 09:51 Family: Fabaceae Cycle: Perennial Plant type: Broadleaf Birdfoot Trefoil flowers Photo by: Albert Herring CC 2.0 Biology Lotus corniculatus can be identified by its unique shaped leaves that alternate on the main stem, are trifoliate (3 terminal leaflets at the apex), […]
Weeds: Bittercress (Shotweed, Hairy bittercress) – Cardamine hirsuta categories: A-B Weeds last review date: 2025-09-14 10:17 Family: Brassicaceae (Cruciferae) Cycle: Winter annual Plant type: Broadleaf Hairy bittercress rosette (1) Photo by: T.W. Miller Biology Little bittercress is a fall/winter-germinating annual species growing to less than five inches tall. Leaves are compound with one large terminal […]
Weeds: Bittersweet nightshade (European bittersweet) – Solanum dulcamara categories: A-B Weeds last review date: 2025-09-14 10:25 Family: Solanaceae Cycle: Perennial Plant type: Broadleaf Bittersweet nightshade fruits Photo by: T.W. Miller Biology Bittersweet nightshade is a trailing to climbing, viny plant with stems reaching up to ten feet. The dark green leaves are alternate on the […]
Weeds: Black medic – Medicago lupulina categories: A-B Weeds last review date: 2025-09-14 10:28 Family: Fabaceae (Leguminosae) Cycle: Annual Plant type: Broadleaf Black medic stem and leaves Photo by: T.W. Miller Biology Black medic is very clover-like in appearance and is sometimes called Japanese clover. Leaves are alternate on the stems and divided into three […]
Weeds: Blackberry (Himalayan, Evergreen, Pacific) – Rubus spp. categories: A-B Weeds last review date: 2025-09-14 10:32 Family: Rosaceae Cycle: Perennial Plant type: Broadleaf Blackberry fruit Photo by: T.W. Miller Biology Several species of blackberries may be considered weeds. Among these are evergreen or cutleaf blackberry (Rubus laciniatus), the native dewberry or Pacific blackberry (R. ursinus), […]
Weeds: Blue mustard (Purple mustard, Tenella mustard) – Chorispora tenella categories: A-B Weeds last review date: 2025-10-13 09:52 Family: Brassicaceae (Cruciferae) Cycle: Winter annual Plant type: Broadleaf Blue mustard with flowers Photo by: J.A. Kropf Biology Blue mustard is a leafy, taprooted winter annual. Plants branch primarily from the base, with some branching of the […]
Weeds: Brackenfern, western – Pteridium aquilinum categories: A-B Weeds last review date: 2025-09-14 10:40 Family: Dennstaedtiaceae (Polypodiaceae) Cycle: Perennial Plant type: Other Western brackenfern fronds Photo by: R. Parker Biology Brackenfern grows from creeping rhizomes, which can spread the plant over a large area. The hairy rhizomes are brown and woody. Leaves (fronds) are generally […]
Weeds: Buffalobur – Solanum rostratum categories: A-B Weeds last review date: 2025-09-14 10:45 Family: Solanaceae Cycle: Annual Plant type: Annual Buffalobur with flowers Photo by: D.G. Swan Biology Buffalobur is an exceptionally spiny annual plant growing about two feet high. The alternate leaves have deep, rounded lobes and are two to five inches long. The […]
Weeds: Bull thistle – Cirsium vulgare categories: A-B Weeds last review date: 2025-09-14 10:52 Family: Asteraceae (Compositae) Cycle: Biennial Plant type: Broadleaf Bull thistle flower Photo by: J.A. Kropf Biology A first-year plant of bull thistle is a rosette of deeply lobed, wavy-margined leaves. The upper surface of the leaves is prickly and hairy, while […]
Weeds: Buttercup, creeping – Ranunculus repens categories: A-B Weeds last review date: 2025-09-14 10:56 Family: Ranunculaceae Cycle: Perennial Plant type: Broadleaf Creeping buttercup flowers Photo by: T.W. Miller Biology Creeping buttercup is a creeping perennial plant that is usually fairly low growing. The stems are hairy and root at the nodes when they contact the […]
Weeds: Butterfly bush – Buddleja davidii categories: A-B Weeds last review date: 2025-09-14 11:04 Family: Scrophulariaceae Cycle: Perennial Plant type: Broadleaf Buddleja davidii ‘Fascination’ Photo by: Ptelea; CC BY-SA 3.0 Biology Butterfly bush, Buddleja davidii, is a deciduous shrub that grows from 3 to 15 ft tall. Until only recently, this species was celebrated for […]
Weeds: Canada thistle – Cirsium arvense categories: C-E Weeds last review date: 2025-09-15 07:14 Family: Asteraceae (Compositae) Cycle: Perennial Plant type: Broadleaf Canada thistle leaves and flower Photo by: T.W. Miller Biology Canada thistle is an aggressive, spreading weed. The aboveground portions of the plants die back in the winter, but resprout from perennial roots […]
Weeds: Catchweed bedstraw (Cleavers) – Galium aparine categories: C-E Weeds last review date: 2025-09-15 07:17 Family: Rubiaceae Cycle: Annual Plant type: Broadleaf Catchweed bedstraw leaf whorls Photo by: T.W. Miller Biology Catchweed bedstraw is a weakly erect to sprawling plant from a slender taproot. Stems are weak, climbing or twining to over six feet in […]
Weeds: Catsear, common (False dandelion) – Hypochaeris radicata categories: C-E Weeds last review date: 2025-09-15 07:20 Family: Asteraceae (Compositae) Cycle: Perennial Plant type: Broadleaf Common catsear rosette Photo by: J.A. Kropf Biology Common catsear, also known as false dandelion or spotted catsear, grows in a rosette, with all the leaves at the base of the […]
Weeds: Chickweed, common and mouseear – Stellaria media, Cerastium fontanum ssp. vulgare categories: C-E Weeds last review date: 2025-09-15 07:26 Family: Caryophyllaceae Cycle: Annual, Perennial Plant type: Broadleaf Common chickweed leaves and flowers Photo by: R. Parker Biology COMMON CHICKWEED reproduces both by seeds and by many creeping stems which can root at the nodes. […]
Weeds: Clover – Trifolium spp. categories: C-E Weeds last review date: 2025-09-15 07:28 Family: Fabaceae (Leguminosae) Cycle: Various Plant type: Broadleaf Clover flowers Photo by: R. Parker Biology Clovers, depending on species, may be annuals or perennials. Typically, clovers are fairly low-growing, herbaceous plants. The leaves are divided into three leaflets which are attached to […]
