Key identifying traits
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Plant stems grow erect up to 1’ tall
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Leaves are divided into short narrow
segments
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Heads are cone-shaped and a
yellowish green color with each head surrounded by overlapping
bracts with no ray petals
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Crushed heads give off a odor
likened to pineapple
Biology and ecology
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An annual plant reproducing by seeds
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Pineapple-weed is a native to
western North America but now considered naturalized in the U.S.
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It is a nuisance in lawns and
gardens and is also found in croplands and along roadsides
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Similar to mayweed chamomile which
has a unpleasant odor and white ray flowers
Control
Prevention –
Learn to identify plants; start monitoring early in the season
Biological –
No known biological control in our area
Cultural –
Plant competitive grass or other cover crops
Mechanical –
It can be hand pulled but does not effectively mowed
Chemical –the
PNW Weed Management handbook does not have it listed as a problem
weed but other sources list mixtures such as Trimec as effective. Also
a pre-emergent herbicide application can help prevent seed germination
*University of California lists
Chamomilla suaveolens as
the scientific name* of this plant. |
