Longspine sandbur

(Cenchrus longispinus)

Annual grass with sharp, spiny burs. Native to the subtropical regions of North America but not native to Canada.

Quick Identification:

• Sharp, spiny burs.
• Light green leaves.
• Leaf sheaths are flattened, very loose, and have a tuft of short hairs where they join the blade. Stems usually are both upright and flat along the ground.

Interesting Facts:

Longspine sandbur

Longspine sandbur seeds on a boot

Longspine sandbur burs

Longspine sandbur

1/7

Flowers:

Since it is a grass it does not have flowers but it does have an inflorescence that produces seeds.

The burs are so sharp they can pin a leather glove to your finger. They can also puncture bike tires and are often noticed when stuck to shoes and clothing.

Management:

Longspine sandbur may be controlled by shallow tillage, hoeing or hand pulling. Repeated mowing every 3 weeks in the spring and summer will reduce seed production. Plants are difficult to identify prior to seed production. Bag and dispose of seeds in a landfill.

Reproduction and Dispersal:

Spreads only by seed. Seeds can stay viable in the seed bank for around 3 years.

Habitat Preference:

Longspine sandbur prefers sandy soils and disturbed sites at low elevations. It does well in hot, dry conditions.

Leaves and Stems:

Stems (0.25-0.75 m) typically grow upright, but can branch and spread flat along the ground. Leaf sheaths are flattened, very loose, and have a tuft of short hairs where they join the blade.

Seeds:

Seeds are round and spiky (4-6 mm wide). Longspine sandbur reproduces entirely from seed. Germination begins in spring and continues throughout the summer. Seeds begin to develop near the beginning of July.

The spiky burs readily hook on to human clothing and animal fur. Since it only spreads by seed preventing seed production for at least 3 years is needed to control an infestation.

Roots:

Small shallow, fibrous root system.

Back