Helianthus praecox subsp. praecox

Common names: Texas sunflower
EndemicConservation concern
Synonyms: Helianthus debilis subsp. praecox
Treatment appears in FNA Volume 21. Treatment on page 152. Mentioned on page 151.

Stems procumbent to erect, branches horizontal, moderately hispid or hirsute. Leaves (at least larger) 3–8 cm. Peduncles 15–30 cm. Phyllary apices short-acuminate. Paleae: middle teeth puberulent. Rays 14–15.2n = 34.


Phenology: Flowering early summer–fall.
Habitat: Sandy soils
Elevation: 0–50 m

Discussion

Of conservation concern.

Selected References

None.

Lower Taxa

None.
hispidulous +  and hispid-hirsute +
not tailed +, rounded +  and obtuse +
pale +  and dark +
connate +  and distinct +
short-attenuate;short-acuminate +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
spiciform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Edward E. Schilling +
Engelmann & A. Gray +
cuneate +  and cordate +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
deltate;ovate +
2 cm20 mm <br />0.02 m <br /> (7 cm70 mm <br />0.07 m <br />) +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
hirsute +  and hispid +
barbellulate +  and barbellate +
Texas sunflower +
reddish +  and yellow +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
compressed +  and obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
0–50 m +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Sandy soils +
in more or less corymbiform , paniculiform or spiciform , arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
1.3 cm13 mm <br />0.013 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
hemispheric +
1.6 cm16 mm <br />0.016 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
sessile +  and petiolate +
3 cm30 mm <br />0.03 m <br /> (?) +  and 8 cm80 mm <br />0.08 m <br /> (?) +
triangular +
serrate +  and serrulate +
2-carpellate +
3-toothed +
0.65 cm6.5 mm <br />0.0065 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
persistent +
coroniform +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
5 cm50 mm <br />0.05 m <br /> (9 cm90 mm <br />0.09 m <br />) +
Flowering early summer–fall. +
short-acuminate +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
30 +  and 39 +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Boston J. Nat. Hist. +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
aristate +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
exalbuminous +
Endemic +  and Conservation concern +
hirsute +, hispid-hirsute +  and hispid +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Helianthus debilis subsp. praecox +
Helianthus praecox subsp. praecox +
Helianthus praecox +
subspecies +
campanulate +
toothed +  and entire +
300 cm3,000 mm <br />3 m <br /> (500 cm5,000 mm <br />5 m <br />) +
40 cm400 mm <br />0.4 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
2 cm20 mm <br />0.02 m <br /> (20 cm200 mm <br />0.2 m <br />) +
shrub +  and subshrub +