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Hairy Crabweed

Fatoua villosa (FAT-oo-uh vil-OH-suh)

Family: Moraceae Non-native

Mulberryweed, in the Moraceae family, is an erect, branched annual herb resembling a mulberry seedling, except stems and leaves are hairy and sticky to the touch (stems of mulberry saplings are not hairy). Leaves are alternate, and roughly triangular in outline with toothed margins. Flowers are in feathery clusters in the leaf axils. Flower clusters are purple when young, fading to dark brown with age. Plants flower from late spring through early fall, then die after frost. Seeds are forcefully expelled at least 4 feet. Seedlings may flower and fruit within 12 days of reaching the 2-leaf growth stage. Seeds germinate from early spring through late fall, resulting in many generations per year. Mulberryweed was first reported for North America in Louisiana in 1964. Since then, it has become widespread and often occurs as a weed in greenhouses and disturbed sites. Although well managed by certain pre-emergent herbicides, populations may continue to build in the absence of aggressive sanitation programs. Herbicide efficacy rankings for this species are based on limited experimental data. The plant is listed as invasive in some states. Diseases, Insect Pests, and Other Plant Problems: Mulberryweed does not have many enemies, is weedy and can become invasive.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 54 attributes.

How it fits the guild

Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Urtica chamaedryoides

Full plant profile

Growing Conditions
Plant type
Annual; Weed
Life cycle
Annual
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a
Light
Dappled Sunlight (Shade through upper canopy all day) | Deep shade (Less than 2 hours to no direct sunlight) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt)
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Moist | Occasionally Wet
NC region
Coastal; Mountains; Piedmont
Growth rate
Rapid
Maintenance
Low
Form & Appearance
Habit / form
Dense; Erect; Multi-stemmed
Texture
Coarse
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Cordate; Deltoid; Ovate
Leaf margin
Crenate; Dentate
Leaf feel
Papery; Velvety
Leaf size
1-3 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
Papery triangular to heart-shaped leaves.
Flower color
Brown/Copper; Green; Purple/Lavender; White
Flower form
Cyme
Flower size
< 1 inch
Flower detail
Feathery, dense clusters of light green pistillate and staminate flowers in the same cymes, with cymes subtended by a thin bract.
Bloom time
Fall; Spring; Summer
Fruit color
White
Fruit type
Achene
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Fruit is a three-anged, white, oval achene with explosively expelled seeds.
Stem color
Green
Stem detail
Erect hairy stems that can secrete a milky sap when cut. Stems are branched with hooked trichomes.
Wildlife & Ecology
Native status
Non-native
Origin
Japan, Australia, Eastern Asia
Distribution
New York, Southeastern United States from Virginia to Florida, west to Texas and Oklahoma, north to the Ohio River Valley. Sporadic populations reported in California and Washington.
Food & Medicine
Harvest time
Fall; Summer
Fruit type
Achene
Landscape Use
Garden tags
#summer annual weed #warm season weed #herbaceous annual #sticky #spreading #hairy stems #hairy leaves #weedy
Problems & Resistance
Problems
Weedy
Propagation
Seed

Planted at Hunnicutt

Nobody’s planted this one yet.