Arenaria congesta

Helianthus maximilianii

Narrow-leaved Sunflower

Southeast of Sedley
30-August-2002

Flora of Alberta states that the achenes of genus Helianthus bear a "pappus of small scales or awns, soon falling off".

Budd's Flora keys genus Helianthus as having "achenes without barbed awns" (italics my own).

It also keys genus Helianthus as having "pappus composed of scales, bristles, or barbs"; not "pappus absent, or present merely as a short crown".

I have found that neither flora easily distinguishes between Helianthus and Rudbeckia (Rudbeckia hirta is Black-eyed Susan) in their keys. However, they do note that the receptacles of Rudbeckia are more conic and the leaves always alternate.

Maximilianii Characteristics

perennials

rootstocks not tuber-bearing

stem conspicuously pubescent below the inflorescence with short white hairs

leaves mostly opposite

leaves generally lanceolate or linear lanceolate

leaves generally folded lengthwise

leaves rough on both sides

involucre bracts narrow, mostly with loose acuminate tips

involucre bracts covered with short white hairs, sometimes ciliate toward the base

disk yellow or light brown

receptacle convex or low conical

Helianthus Characteristics

juice watery, not milky

plants not heavy scented

plants more or less leafy-stemmed

plants not with a woody caudex

leaves not compound

leaves not linear

at least the lower leaves opposite

involucre not glandular nor glutinous

involucre bracts in one or more series, but all of the same nature

receptacle flat or convex, not conic or columnar

receptacle with chaffy scales between the florets

flower heads with both tubular and ray florets

rays conspicuous

ray florets yellow

ligulate (ray) flowers either pistillate or neutral

pappus composed of small scales or awns, soon falling off; not composed of hairs