Common nipplewort (Lapsana communis)

Synonyms: Lampsana communis

Common Names: Nipplewort

Description:

Common nipplewort (Lapsana communis) is a fast-growing annual weed in the aster family, native to Europe and Asia and introduced to North America, where it is now naturalized [1][2][3]. It turns up on disturbed and shaded ground ? gardens, yards, roadsides, riverbanks, and field edges ? and bears many small, pale-yellow, dandelion-like flower heads on branching leafy stems [1][2]. MISIN tracks it as a non-native weed of disturbed ground, though it is a mild weed rather than an aggressive invader [1][2].

Habit:

Common nipplewort is an upright annual that grows about 1 to 3 feet tall, with slender, branching, often reddish stems that have milky sap and fine hairs near the base [1][2]. Its lower leaves have a distinctive shape ? a large, rounded end lobe with one or two small lobes lower down on each side of the leaf stalk, the little lobes giving the plant its name; the upper leaves are smaller, simple, and toothed [1]. The flowers are small pale-yellow heads, only about ? to ? inch across, made up of a single ring of strap-shaped petals (ray florets), carried in open, branching clusters at the top of the plant [1][2]. A key giveaway is the seed: unlike dandelions and most of its yellow-flowered relatives, its small dry seeds have no fluffy parachute of hairs [1][2].

It is easiest to spot from early summer into fall (about June through September), when the airy sprays of small yellow flower heads are open above the foliage [1]. Earlier in the season, look for the rosette and lower leaves with that large end lobe and the small "nipple" side lobes on shaded, disturbed ground [1].

At-a-glance cues:

1. Many small (??? inch) pale-yellow, dandelion-like flower heads in open, branching clusters [1][2]
2. Lower leaves with a large rounded end lobe and small side lobes near the base [1]
3. Slender, branching, often reddish stems with milky sap [1][2]
4. Small dry seeds with no fluffy tuft of hairs ? unlike dandelion and most yellow-flowered relatives [1][2]

Leaves:

1. Arrangement: alternate along the stem [1][2]
2. Shape: lower leaves with a large rounded end lobe plus one or two small side lobes near the base; upper leaves smaller, simple, oval to lance-shaped [1]
3. Margin: toothed [1][2]
4. Size: lower leaves up to about 6 inches long [1]
5. Surface: thin, green, with milky sap when broken [1][2]

Stems:

1. Habit: an erect annual (sometimes biennial), 1?3 feet tall, branching toward the top, with milky sap [1][2]
2. Surface: slender, slightly ridged, often reddish green, with white hairs especially near the base [1]

Flowers:

1. Color: pale yellow [1][2]
2. Shape: small heads about ??? inch across, each with a single ring of about 8?20 strap-shaped ray florets (no central disk of a different type) [1][2]
3. Arrangement: in open, branching clusters of many heads at the top of the plant [1][2]
4. Bloom time: early summer into fall, about June through September [1]

Fruit and seeds:

1. Fruit type: a small, dry, curved, ribbed seed (achene) about 1/8 inch long [1]
2. Distinguishing trait: the seed has no pappus ? no fluffy tuft of hairs ? unlike dandelion and most other yellow-flowered relatives [1][2]
3. Dispersal: by seed, which drops near the plant and moves in soil and on equipment [1][2]

Habitat:

Common nipplewort is native to Europe and Asia and was introduced to North America, where it is now naturalized across much of the continent [1][2][3]. It is a plant of disturbed and shaded ground rather than a strong invader of intact natural habitat [1][2].

It grows in full sun to light shade on moist to dry soils and tolerates shade better than many weeds [1]. Look for it in gardens, yards, shady campgrounds, along roadsides and walls, on gravelly riverbanks, and at the edges of fields and woods, including as a weed of crops [1][2].

Reproduction:

Common nipplewort spreads only by seed. A single plant makes many small seeds, and because they have no fluffy parachute they mostly drop close to the plant rather than blowing far ? though they travel readily in garden soil and on tools, footwear, and mowers [1][2]. It often shows up in a shaded bed or yard from seed carried in with soil or simply blown in from a nearby patch [1].

It is a fast annual (sometimes lasting into a second year): plants sprout, grow up, flower from early summer into fall, set seed, and die [1][2]. For control, the key timing is to remove plants before the flower heads ripen into seed, since seed is the only way it spreads [1].

Impact and Damage:

For homeowners, common nipplewort is a minor nuisance weed rather than a hazard. It is not known to be toxic ? its young leaves have a history of use as an edible green ? and it turns up mainly on disturbed and shaded ground such as garden beds, yards, and shady edges, where it competes with other low plants for space [1][2]. Because it tolerates shade, it can fill in shaded spots where many weeds will not grow [1].

For natural area stewards, common nipplewort is a low-level concern compared with aggressive habitat invaders. It is a weed of disturbed, shaded, and open ground ? trail edges, campgrounds, riverbanks, and field margins ? and does not typically take over healthy, intact natural plant communities [1][2]. Removing patches from disturbed shaded areas before they seed keeps it from filling in ground that native plants could use [1][2].

Similar species:

Common nipplewort is one of many yellow-flowered members of the aster family and is easily lumped with them at a glance. Its surest marks are its small pale-yellow heads of strap-shaped petals in airy branched sprays, its lower leaves with a big end lobe and small side lobes, and ? most reliably ? its seeds, which lack the fluffy tuft of hairs that its relatives have [1][2].

Common dandelion (Taraxacum officinale) has similar yellow strap-petaled flower heads and is the plant people most often think of first. It is easy to separate: dandelion makes a single flower head on a leafless, hollow stalk rising from a basal rosette, and its seeds form the familiar fluffy "clock," while nipplewort has leafy, branching stems carrying many small heads and seeds with no fluff [1][2].

Smooth hawksbeard (Crepis capillaris) is a weedy relative with a similar branching spray of small yellow heads. It is distinguished by its seeds, which carry a tuft of soft white hairs (a pappus) that nipplewort's seeds completely lack, and by its more deeply cut, often clasping leaves [2].

Monitoring and rapid response:

Signs to watch for:

1. Slender, branching, often reddish leafy stems 1?3 feet tall on disturbed or shaded ground [1][2]
2. Lower leaves with a large end lobe and small side lobes; milky sap when a stem is broken [1]
3. Open, branching sprays of many small pale-yellow flower heads from early summer into fall [1][2]

What you can do:

1. Hand-pull or hoe plants while young, before the flower heads ripen into seed ? the shallow taproot comes up easily in moist soil [1]
2. Cut or pull flowering plants and bag the seeding heads rather than composting them, since seed is the only way it spreads [1][2]
3. Keep shaded garden soil mulched or planted so seeds have less open ground to colonize [1]
4. Catch and pull new plants over the season; repeating this before seed-set draws down the seed in the soil [1]
5. For natural areas, volunteer crews can focus on disturbed shaded ground ? trail edges, campgrounds, riverbanks ? pulling patches before they seed and revisiting to catch new seedlings [1][2]

When to call a professional:

1. Large or recurring infestations across gardens, crops, or shaded ground where hand removal cannot keep up [1]
2. Patches that keep returning from the soil seed bank season after season despite removal [1]
3. For chemical control options, contact a licensed applicator or your local cooperative extension office.

Report sightings to MISIN. Help track this species' spread by submitting observations through the MISIN web site or the MISIN mobile app (Android, iOS, Windows, and macOS). Photos at multiple angles paired with a precise GPS location are the most valuable data for confirming new occurrences and triggering rapid-response review.

Credits:

1. Hilty J. Illinois Wildflowers. Nipplewort (Lapsana communis). illinoiswildflowers.info
2. Native Plant Trust, Go Botany. Lapsana communis (common nipplewort). gobotany.nativeplanttrust.org
3. Plants of the World Online (POWO), Royal Botanic Gardens, Kew. Lapsana communis L. powo.science.kew.org

---