The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

field clover, hop clover, hop trefoil, low hop-clover, pinnate hop clover

balloon sack clover, cowbag clover, dwarf sack clover, poverty clover

Habit Herbs annual, 5–40 cm, slightly villous or glabrous. Herbs annual, 1–30 cm, glabrous.
Stems

erect to ascending, branched.

erect or decumbent, branched.

Leaves

pinnate;

stipules ovate-lanceolate, 0.5–0.8 cm, margins entire, glandular, apex acuminate;

petiole 0.3–2 cm;

lateral leaflet petiolules 0.5–0.6 mm, terminal leaflet stalk 3–5 mm;

leaflets 3, blades rhombic to obovate, 0.4–1.5 × 0.4–0.8 cm, base cuneate, lateral veins prominent, ± parallel, ascending, margins denticulate distally, apex truncate or retuse, surfaces strigose adaxially.

palmate;

stipules sheathing proximally, ovate-oblong to lanceolate, 0.4–1.3 cm, margins entire or serrulate, apex short triangular-cuspidate;

petiole 1–5 cm;

petiolules to 1 mm;

leaflets 3, blades lanceolate, linear, obovate, or oblanceolate, 0.4–2.5 × 0.1–0.7 cm, base cuneate, veins moderately thickened abaxially, margins entire, serrate, or pinnately lobed, apex rounded, truncate, acute, or retuse, surfaces glabrous.

Inflorescences

axillary, 30–60-flowered, globose or broadly ovoid, 0.8–1.5 × 0.7–1 cm;

involucres absent.

axillary or terminal, 3–15-flowered, globose or depressed-globose, 0.5–1.5 × 0.5–1.5 cm;

involucres flattened, 3–13 mm, ± distinct or incised 1/2 their length, lobes 5–7, linear to elliptic or irregular, or vestigial, reduced to narrow ring, apex rounded to broad and irregularly erose, not split.

Peduncles

1.5–3.5 cm.

2–6 cm.

Pedicels

reflexed, 0.7–1.2 mm;

bracteoles a fringe of red setae.

straight, 0–0.5 mm;

bracteoles absent.

Flowers

4.3–5 mm;

calyx campanulate, strongly bilabiate, 1.3–1.5 mm, glabrous, veins 5, tube 0.3–0.6 mm, lobes unequal, adaxial deltate, very short, lateral and abaxial linear-subulate, each tipped with 1 or 2 stiff hairs, orifice open;

corolla yellow becoming brown, 3.5–6 mm, ribbed, banner persistent, obovate, enveloping other petals, boat-shaped, 4.3–5 × 2.8–3.2 mm, apex broad, acute.

3–10 mm;

calyx campanulate, 2–5 mm, glabrous, veins 5, tube 1–2.5 mm, lobes unequal, triangular-lanceolate or subulate, orifice open;

corolla white or pink, 3–11 mm, inflated in fruit, banner broadly ovate, 4–7 × 3–8 mm, apex rounded, broad, acute, or retuse.

Legumes

stipitate, oblong, 2–2.5 mm.

sessile or stipitate, ovoid, obovoid, or oblong, 2–4 mm.

Seeds

1 or 2, yellow, ellipsoid, 1–1.5 mm, smooth, lustrous.

1–6, gray or tan, mottled, mitten-shaped, 1.2–1.6 mm, irregularly bumpy.

2n

= 14.

= 16.

Trifolium campestre

Trifolium depauperatum

Phenology Flowering Jun–Aug.
Habitat Roadsides, fields.
Elevation 0–1700 m. (0–5600 ft.)
Distribution
from FNA
AK; AL; AR; AZ; CA; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; TN; TX; VA; VT; WA; WI; WV; WY; BC; NB; NF; NS; ON; PE; QC; SPM; Europe; w Asia; n Africa [Introduced in North America; introduced also in South America, e Asia (China), s Africa, Pacific Islands (Hawaii, New Zealand), Australia]
[WildflowerSearch map]
[BONAP county map]
from USDA
w North America; nw Mexico; c North America; South America (Chile, Peru)
[WildflowerSearch map]
[BONAP county map]
Discussion

Trifolium filiforme Linnaeus and T. procumbens Linnaeus are rejected names that were used historically for T. campestre (J. E. Dandy 1958; N. J. Turland et al. 1996).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 3 (3 in the flora).

The three varieties of Trifolium depauperatum are relatively easily distinguished by characteristics of the involucres and fruit stipes. Leaf morphology is not helpful in making the distinctions; in each variety, leaf margins can range from nearly entire or toothed or laciniate. In the phylogenetic treatment by N. W. Ellison et al. (2006), T. depauperatum is not allied with T. fucatum and other clovers with inflated corollas but rather with T. obtusiflorum, T. trichocalyx, and T. willdenovii (although with weak support).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Involucres reduced to narrow vestigial ring; inflorescences 1–1.5 cm diam.; flowers 7–10 mm; legumes ovoid, 3–4 mm, sessile.
var. depauperatum
1. Involucres with evident bracts; inflorescences 0.5–1 cm diam.; flowers 3–8 mm; legumes oblong, ovoid, or obovoid, 2–4 mm, sessile or stipes 0.5–1 mm.
→ 2
2. Involucral lobes broad, irregular, with broad, hyaline margins and reticulate veins; legumes oblong, 3–4 mm, ± sessile.
var. amplectens
2. Involucral lobes oblong, often with narrow hyaline margins and raised, parallel veins; legumes ovoid or obovoid, 2–3 mm, stipes 0.5–1 mm.
var. truncatum
Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Trifolium Fabaceae > subfam. Faboideae > Trifolium
Sibling taxa
T. albopurpureum, T. alexandrinum, T. amoenum, T. amphianthum, T. andersonii, T. andinum, T. angustifolium, T. appendiculatum, T. arvense, T. attenuatum, T. aureum, T. barbigerum, T. barnebyi, T. beckwithii, T. bejariense, T. bifidum, T. bolanderi, T. brandegeei, T. breweri, T. buckwestiorum, T. calcaricum, T. carolinianum, T. cernuum, T. ciliolatum, T. columbinum, T. cyathiferum, T. dasyphyllum, T. dedeckerae, T. depauperatum, T. dichotomum, T. douglasii, T. dubium, T. echinatum, T. eriocephalum, T. fragiferum, T. friscanum, T. fucatum, T. glomeratum, T. gracilentum, T. grayi, T. gymnocarpon, T. haydenii, T. hirtum, T. howellii, T. hybridum, T. hydrophilum, T. incarnatum, T. jokerstii, T. kentuckiense, T. kingii, T. lappaceum, T. latifolium, T. leibergii, T. lemmonii, T. longipes, T. lupinaster, T. macilentum, T. macraei, T. macrocephalum, T. medium, T. microcephalum, T. microdon, T. monanthum, T. mucronatum, T. nanum, T. nigrescens, T. obtusiflorum, T. oliganthum, T. ornithopodioides, T. owyheense, T. palmeri, T. parryi, T. pinetorum, T. piorkowskii, T. plumosum, T. polyodon, T. pratense, T. productum, T. reflexum, T. repens, T. resupinatum, T. retusum, T. rollinsii, T. siskiyouense, T. sonorense, T. stoloniferum, T. striatum, T. subterraneum, T. suffocatum, T. thompsonii, T. tomentosum, T. trichocalyx, T. variegatum, T. vesiculosum, T. virginicum, T. willdenovii, T. wormskioldii
T. albopurpureum, T. alexandrinum, T. amoenum, T. amphianthum, T. andersonii, T. andinum, T. angustifolium, T. appendiculatum, T. arvense, T. attenuatum, T. aureum, T. barbigerum, T. barnebyi, T. beckwithii, T. bejariense, T. bifidum, T. bolanderi, T. brandegeei, T. breweri, T. buckwestiorum, T. calcaricum, T. campestre, T. carolinianum, T. cernuum, T. ciliolatum, T. columbinum, T. cyathiferum, T. dasyphyllum, T. dedeckerae, T. dichotomum, T. douglasii, T. dubium, T. echinatum, T. eriocephalum, T. fragiferum, T. friscanum, T. fucatum, T. glomeratum, T. gracilentum, T. grayi, T. gymnocarpon, T. haydenii, T. hirtum, T. howellii, T. hybridum, T. hydrophilum, T. incarnatum, T. jokerstii, T. kentuckiense, T. kingii, T. lappaceum, T. latifolium, T. leibergii, T. lemmonii, T. longipes, T. lupinaster, T. macilentum, T. macraei, T. macrocephalum, T. medium, T. microcephalum, T. microdon, T. monanthum, T. mucronatum, T. nanum, T. nigrescens, T. obtusiflorum, T. oliganthum, T. ornithopodioides, T. owyheense, T. palmeri, T. parryi, T. pinetorum, T. piorkowskii, T. plumosum, T. polyodon, T. pratense, T. productum, T. reflexum, T. repens, T. resupinatum, T. retusum, T. rollinsii, T. siskiyouense, T. sonorense, T. stoloniferum, T. striatum, T. subterraneum, T. suffocatum, T. thompsonii, T. tomentosum, T. trichocalyx, T. variegatum, T. vesiculosum, T. virginicum, T. willdenovii, T. wormskioldii
Subordinate taxa
T. depauperatum var. amplectens, T. depauperatum var. depauperatum, T. depauperatum var. truncatum
Synonyms Chrysaspis campestris Lupinaster depauperatus
Name authority Schreber in G. F. Hoffmann: Deutschl. Fl. 4: 16, plate 253. (1804) Desvaux: J. Bot. Agric. 4: 69, plate 32, fig. 2. (1814)
Web links