Ontario Weeds: Tall buttercup
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Excerpt from Publication 505, Ontario Weeds,
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Table of Contents
- Name
- Other Names
- Family
- General Description
- Stems and Roots
- Flowers and Fruit
- Habitat
- Similar Species
- Caution
- Related Links
Name: Tall buttercup, Ranunculus
acris L.,
Other Names: renoncule âcre, Field
buttercup, Meadow buttercup, Tall crowfoot, Tall field buttercup,
bouton-d'or
Family: Buttercup Family (Ranunculaceae)
General Description: Perennial, reproducing
only by seed.
Creeping buttercup (left); Tall buttercup (right).
Tall buttercup. A. Base of plant. B. Lower leaf. C. Flowering
branch.
Stems & Roots: Stems 1 or several
from a thick rootstalk with numerous, spreading, coarse, fibrous
roots, erect, 30-100cm (12-40in.) high, branched in the upper part,
hairy throughout; leaves basal and alternate (1 per node) on the
stem, softly hairy, very deeply lobed and toothed; basal and lower
leaves long-stalked, the blade deeply divided into 5 main lobes
palmately arranged (like fingers from the palm of the hand), each
of the 5 lobes irregularly jagged or coarsely toothed; middle leaves
with similar shape but nearly stalkless; upper leaves progressively
smaller with fewer and smoother lobes; the base of each leafstalk
flattened and partly surrounding the stem at each node.
Flowers & Fruit: Flowers bright
yellow, about 2-3cm (4/5-1¼in.) in diameter, grouped on long
stalks in a much-branched inflorescence; sepals 5, green and small;
petals 5; stamens numerous around the cluster of tiny pistils; after
the petals fall, the cluster of seeds is nearly spherical with each
seed about 3mm (1/8in.) long, flattened, egg-shaped in outline with
a short hooked tip. Flowering and setting seed from late May throughout
the summer and fall.
Habitat: Tall buttercup is one of
the most common weeds of pastures, meadows, and roadsides throughout
Ontario. It can grow in a wide variety of habitats from low wet
meadows, to rich woods, to the coarse soils of gravel pits and railroad
cinders. There are many species of native and introduced buttercups,
but only Tall buttercup is of wide importance as a weed.
Similar Species: It is distinguished by
its erect habit, the lower and middle leaves being similar in appearance,
and the leaf blades deeply lobed but not completely divided into
sections with distinct stalks.
Caution: The Buttercups have a bitter, acrid juice which causes severe pain and inflammation when grazed by livestock. They are normally avoided, but when other feed becomes scarce they may be grazed with serious consequences.
Related Links
... on general Weed
topics
... on weed identification, order OMAFRA
Publication 505: Ontario Weeds
... on weed control, order OMAFRA
Publication 75: Guide To Weed Control
For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca