Asparagus officinalis
Asparagus
asparagus, common asparagus, garden asparagus
asparagus, asparagus-fern, asperge, espárrago
annual, densely branched distally;
branches finely dissected, ascending to perpendicular, unarmed;
cladophylls in clusters of (2–)4–15(–25) per node, filiform, straight or curved, 1–3 cm.
photosynthetic, erect, spreading or climbing, branched;
cladophylls solitary or fasciculate, in nodes of reduced, scarious leaves.
scalelike, 3–4 mm;
blade lanceolate, base hardened.
small, scale-like, membranous, or sometimes spiny with hardened base, subtending cladophylls.
in axillary racemes, 1–3-flowered.
axillary or terminal, racemose, or umbellate, paired or solitary;
racemes short.
some unisexual;
perianth campanulate, yellow or yellowish green;
tepals connate 1–2 mm, greenish white, 3–8 × 1–2 mm;
pedicel 8–12 mm, jointed at or above middle.
bisexual or unisexual;
perianth greenish, white, or yellowish, campanulate to rotate;
tepals 6, distinct or shortly connate basally, equal;
stamens 6, distinct, equal;
anthers versatile, 2-locular, dehiscence introrse;
ovary superior, 3-locular, septal nectaries present;
style 3-branched distally;
pedicel with conspicuous joint.
baccate, red or purplish black, globose, often with tepals persisting at base.
red, 6–10 mm.
2–4.
1–6, black, globose to angular.
= 10.
= 20, 40.
Asparagus officinalis
Asparagus
Eaten as a vegetable, Asparagus officinalis has been widely cultivated for its young shoots since ancient Greek times. The species is naturalized in many temperate climates. Mature asparagus has caused poisoning in cattle (J. M. Kingsbury 1964). Young plants can cause dermatitis, and the red berries are suspected of poisoning humans (E. M. Schmutz and L. B. Hamilton 1979). The species is dioecious (J. E. Lazarte and B. F. Palser 1979), and homomorphic sex chromosomes have been identified (H. Loptien 1979).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Species 170–300 (4 in the flora).
Asparagus is a moderately important horticultural genus, with one species commonly grown for its edible young shoots and a number of others grown ornamentally. The genus is treated here in a broad sense (K. Kubitzki and P. J. Rudall 1998; W. S. Judd 2001) and encompasses species that have been segregated in several genera (A. L. Takhtajan 1997; S. T. Malcomber and Sebsebe D. 1993). Embryological features (P. J. Rudall et al. 1998) and DNA-based analyses (M. W. Chase et al. 1996; M. F. Fay et al. 2000; P. J. Rudall et al. 1997) support the monophyly of Asparagus and the Asparagaceae.
Asparagus virgatus Baker has been collected once as a garden escape in East Baton Rouge Parish, Louisiana, but it is probably not truly naturalized in the flora. Asparagus falcatus Linnaeus occasionally persists after cultivation in the Miami–Dade County area of southern Florida (W. S. Judd 2001).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Plants erect; some flowers unisexual. | A. officinalis |
1. Plants scrambling, twining, or arching; all flowers bisexual. | → 2 |
2. Cladophylls solitary at each node, broadly lanceolate to ovate, with 20–24 veins. | A. asparagoides |
2. Cladophylls in fascicles of 3–20 per node, linear or filiform, with single vein. | → 3 |
3. Cladophylls filiform; pedicels 1–3 mm; inflorescences 1–4-flowered terminal umbels; berries purplish black. | A. setaceus |
3. Cladophylls flattened; pedicels 5–8 mm; inflorescences 5–9(–17)-flowered axillary racemes; berries red. | A. aethiopicus |
- Local floras:
BC, 
OR, 
WA - Local Web sites:
CalFlora, CalPhotos, 
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
- Local floras: CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
