Pineapple Weed

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Biology

This is an annual weed, reproducing by seeds. The stems are erect, up to 40 cm tall, branched, hairless, and smooth. The leaves are alternate, hairless, very finely divided, and pineapple scented when crushed. The flowers are very small, grouped into head, and yellowish-green in colour. Flower heads are dome-shaped and resemble miniature pineapples. The tubular florets are surrounded by a series of involucral bracts which have broad whitish translucent edges. The seeds are olive or brown in colour, 1.0 x 0.3 mm in size, and one per flower.

Scouting Techniques

Take a minimum of 20 weed counts across the field. Check roadsides, waste areas, yards, and disturbed ground for patches of this weed. May occur in high traffic areas such as walking paths.

Effects On Crop Quality

Competes with desirable plant species.