Astragalus gilviflorus

Eriogonum flavum

Yellow Umbrellaplant

Involucre Cut Open

Oro Lake Regional Park
27-June-2011

Note a portion of the involucre has been removed to reveal the base of the pedicels.

The inflorescence is an umbel of fascicles. There are a number of linear bracts at the base of the rays of the umbel. Each fascicle contains several flowers and is partially enclosed by a membranous involucre. Note that Flora of Alberta describes the inflorescence as a compound umbel in the keys.

Flavum: Answers to key questions in Budd's Flora and Flora of Alberta leading to this species.

plants perennial; NOT [plants annual]

NOT [stem diffusely branched, the branches slender]

leaves hirsute above; NOT [leaves glabrous]

inflorescence a more or less dense umbel; NOT [inflorescence a diffusely branched raceme] (BF)

inflorescence a compound umbel; NOT [inflorescence a simple umbel] (FOA)

NOT [flowers in reflexed heads] (FOA)

inflorescence subtended by leaf-like bracts; NOT [inflorescence subtended by small, reduced bracts]

bracts ascending; NOT [bracts spreading or reflexed]

bracts linear; NOT [bracts lanceolate or oblong]

perianth pubescent at base; NOT [perianth glabrous]

Eriogonum: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus.

NOT [dwarf annual, leaves subopposite, calyx 3-parted, stamens3]

leaves without stipules

flower clusters subtended by an involucre

stamens 9; NOT [stamens 8 or fewer]

Polygonaceae: Answers to key questions in Budd's Flora leading to this family. Not all the answers lead to all members of Polygonaceae, but they all do lead to genus Eriogonum.

herbs; NOT [shrubs or trees]

land plants; NOT [water plants]

plants not parasitic on trees, rooted in soil or water; NOT [plants parasitic on branches of trees]

plants with stems or stemless, but with more than one pair of leaves; NOT [plants stemless with a single pair of large reniform leaves]

leaves alternate; lower ones sometimes opposite; NOT [leaves opposite]

leaves without stipules; NOT [leaves with stipules free or sheathing the stem]

leaves not compound and not very deeply divided; NOT [leaves compound or simple, but very deeply divided]

leaves not orbicular or reniform; NOT [leaves orbicular or reniform]

flowers colored; NOT [flowers small, numerous, greenish]

perianth segments 6, in two series; NOT [perianth segments 2-5]

stamens and pistils in each flower; NOT [stamens or pistils in separate flowers on the same plant]

fruit dry when ripe; NOT [fruit fleshy when ripe]