Key to Frangula

View taxon page for Frangula

(For a list of species in Frangula, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Leaves deciduous, blades thin

2. Fruit 3-stoned; 

leaf 

Organ arising from a stem, generally composed of a stalk (petiole) and a flat, expanded, green, photosynthetic area (blade); distinguished from a leaflet by the presence in its axil of a bud, branch, thorn, or flower; sometimes with lateral, basal appendages (stipules); either simple (toothed, lobed, or dissected but not divided into leaflets) or compound (divided into leaflets).

 

blade 

Expanded portion of a leaf, petal, or other structure, generally flat but sometimes rolled, cylindric, wavy, or cupped.

(50)80–150 mm ..... F. purshiana

3. Leaf blade blue- or green-gray, ± glaucous when fresh, 

papillate 

Pertaining to a surface (e.g., of a leaf, stigma, fruit) bearing small, rounded or conic protuberances (papillae).

, densely hairy or adaxially velvety, light green, abaxially sparsely to densely hairy ..... subsp. ultramafica (2)

3' Leaf blade green, not papillate, glabrous to sparsely hairy

4. Leaf base 

tapered 

Gradually (not abruptly) narrower or smaller at base or tip.

; KR, CaR, n&c SN ..... subsp. annonifolia

4' Leaf base rounded or 

cordate 

Heart-shaped; often pertaining to a leaf in which the blade base on both sides of the petiole is rounded and convex.

; NCo, KR, NCoRO, NCoRH ..... subsp. purshiana

2' Fruit 2(3)-stoned; leaf blade 15–80 mm ..... F. rubra

5. Leaf blade finely hairy ..... subsp. yosemitana

5' Leaf blade glabrous or abaxially 

puberulent 

Minutely hairy.

on midrib, veins

6. Twigs gray; leaves clustered on short-shoots ..... subsp. modocensis

6' Twigs red to gray; leaves scattered along stem

7. Leaf base, tip rounded ..... subsp. obtusissima

7' Leaf base, tip 

acute 

Having a short-tapered, sharp tip, the sides convex or straight and converging at less than a right angle.

..... subsp. rubra

1' Leaves semi-deciduous or evergreen, blades ± leathery or thin

8. Leaves semi-deciduous, fruit 2–3-stoned

9. Leaf blade thin, 20–60 mm, 

elliptic 

In the shape of a flattened circle or ellipse; wider than linear

; fruit 2-stoned ..... F. californica subsp. cuspidata (2)

9' Leaf blade ± leathery, 50–100 mm, widely 

oblong 

Longer than wide, with nearly parallel sides; wider than linear.

or 

ovate 

Egg-shaped (i.e., widest below the middle) in two dimensions (i.e., in one plane), as a leaf.

to obovate; fruit 3-stoned ..... F. purshiana subsp. ultramafica (2)

8' Leaves generally evergreen; fruit generally 2-stoned ..... F. californica

10. Leaf blade ± glabrous or abaxially ± puberulent

11. Leaf blade dark green adaxially, bright green or yellow abaxially; fruit 2-stoned ..... subsp. californica

11' Leaf blade ± yellow-green; fruit 3-stoned ..... subsp. occidentalis

10' Leaf blade adaxially glabrous to 

tomentose 

Covered with densely interwoven, generally matted hairs.

, abaxially glabrous to tomentose, velvety, or silvery

12. Leaf blade adaxially green, glabrous or minutely puberulent, abaxially glabrous to white-tomentose mixed with long hairs

13. Leaf tip abruptly pointed or not, margin 

dentate 

Having margins with sharp, relatively coarse teeth pointing outward, not tipward.

to dentate-serrate, long hairs conspicuous abaxially; c&s SN, Teh, TR, nw PR, SnJt, SNE, DMoj ..... subsp. cuspidata (2)

13' Leaf tip acute to rounded, margin 

entire 

Having margins that are continuous and smooth (i.e., without teeth, lobes, etc.).

to 

serrate 

Having margins with sharp, fine to coarse teeth generally pointing tipward, not outward; margins with such teeth on such primary teeth are doubly serrate.

, long hairs inconspicuous abaxially; DMtns (Clark, New York, Providence mtns) ..... subsp. ursina

12' Leaf blade white-tomentose, or adaxially dull green, glabrous, abaxially white-tomentose or velvety to silvery, long hairs 0.

14. Leaf blade narrowly elliptic, abaxially velvety to silvery ..... subsp. tomentella (2)

14' Leaf blade widely elliptic, abaxially white-tomentose or velvety to silvery

15. Leaf blade adaxially white-tomentose, tip 

obtuse 

Having a short-tapered, blunt tip or base, the sides convex or straight and converging at more than a right angle.

; s KR, NCoRI ..... subsp. crassifolia

15' Leaf blade adaxially glabrous (white-tomentose), tip acute; s KR, NCoR, CaRF, SNF, n SNH, ScV, SnFrB, SCoR, SW ..... subsp. tomentella (2)

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