Hylodesmum nudiflorum (L.) H. Ohashi & R.R. Mill

Naked Tick Trefoil

© DETenaglia

Family - Fabaceae/Faboideae

Stems - Vegetative stem to +/-20cm tall, erect, simple, pubescent, from short caudex. Flowering stems typically naked, spreading horizontally underground from vegetative stem then ascending to +/-1m tall, pubescent, typically simple.

	Vegetative and flowering stem.
© DETenaglia

Leaves - Typically clustered at the apex of the vegetative stem, alternate (appearing whorled), trifoliolate, petiolate. Petiole thickened at base for 3-4mm, angled, glabrous to pubescent, +/-9cm long. Lateral leaflets with petiolule to 2mm long. Petiolule pubescent to pilose. Blade oblique at base, to 7cm long, +3.5cm broad, ovate, entire, acute to obtuse at apex, scabrous. Central leaflet on petiolule to -2cm long. Petiolule pubescent. Blade elliptic to rhombic-ovate, +/-9cm long, +/-5cm broad, pubescent, scabrous.

© DETenaglia

Inflorescence - Terminal raceme elongating in fruit to +30cm. Pedicels to 1.7cm in flower, elongating in fruit, sparse pubescent.

	Inflorescence.
© DETenaglia

Flowers - Corolla pink, papilionaceous. Standard to 1.2cm long, 8mm broad, with purplish spots near base. Wing and keel petals pink (keels lighter), to 9mm long. Wing petals slightly spreading. Stamens monodelphous, glabrous, +/-7mm long. Ovary green, tuberculate, 5mm long. Style white, 2-3mm long. Calyx tube to 1mm long, campanulate, with red spotting at base, sparse pubescent, shallowly 5-lobed. Lobes unequal, spreading in fruit, lowermost acute. Loments with 2-4 segments, puberulent, upper margin almost straight across.

	Calyx.
© DETenaglia

© DETenaglia

© DETenaglia

Flowering - June - August.

Habitat - Open rocky woods, typically in acidic soils.

Origin - Native to U.S.

Other info. - As I have mentioned before, the species in this genus can be difficult to distinguish from one another. That is not the case with this plant. The peculiar growth pattern of the plant makes it simple to ID in the field.
Steyermark lists two varieties for the plant. Variety nudiflorum has no leaves present on the flowering stems. Variety foliolatum (Farwell) Fassett has leaves on the flowering stem. Both varities are common throughout most of Missouri except in the northwest 1/4 of the state, where the species is apparently absent.

Photographs taken in Brown Summit, NC., 7-13-02.