Hogweed - Heracleum sphondylium

Description

Stout medium to tall rather bristly plant. Stem hollow and ridged. Leaves pinnate, often with 5 broad, lobed and toothed segments. Upper leaves with large inflated bases. Flowers white 5 to 10 mm in large umbels up to 15 cm across with 12 to 25 rays. Petals of outer flowers very unequal.

Identification difficulty
ID checklist (your specimen should have all of these features)

Tall, hairy, coarse plant.  Some specimens can have leaves with narrow leaflets.  Flattened seeds

Habitat

Hedgebanks, rough grassland and roadside verges.

When to see it

April to September.

Life History

Biennial or short lived perennial.

UK Status

Common throughout much of Britain.

VC55 Status

Very common in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 605 of the 617 tetrads.

In the current Checklist (Jeeves, 2011) it is listed as Native, frequent

Leicestershire & Rutland Map

MAP KEY:

Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

UK Map

Species profile

Common names
Keck, Kecks, Hogweed, Cow Parsnip
Species group:
Wildflowers
Kingdom:
Plantae
Order:
Apiales
Family:
Apiaceae
Records on NatureSpot:
757
First record:
11/05/1992 (John Mousley;Steve Grover)
Last record:
08/07/2024 (Higgott, Mike)

Total records by month

% of records within its species group

10km squares with records

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Latest images

Latest records

Photo of the association

Phytomyza heracleana

The larvae of the fly Phytomyza heracleana mine the leaves of Hogweed forming a blotch mine between two veins, which has a characteristic sieve-like appearance (where the larva has fed through the upper parenchyma).

Photo of the association

Phytomyza spondylii/pastinacae agg.

The larvae of Phytomyza spondylii and Phytomyza pastinacae produce identical conspicuous, whitish linear mines on the leaves of their larval food plants, especially Hogweed. The mines cannot be reliably separated to species level and for this reason we treat them as an aggregate.