[Willowherbs: The Genus Epilobium East of the Cascade Mts. of Oregon and Washington]

Autumn Willowherb, Tall Annual Willowherb

Epilobium brachycarpum

Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi

Close-up of the flower of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)

A close-up of the flower of tall annual willowherb as seen along FS Road 16 in Logan Valley, Malheur National Forest.........August 20, 2011.

Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)The photo at right shows a close-up side view of the flower of tall annual willowherb as seen at Viento State Park, OR, Columbia River Gorge.............August 25, 2002. This is formerly E. paniculatum var. jucundum.
Characteristics:

Tall annual willowherb is also known as panicled willowherb. It is a taprooted annual wildflower with simple to more often branched stems from 20-100 cm high. The herbage is often glabrous below but glandular hairy above. The leaves are short-petiolate or sessile, linear to narrowly lanceolate or elliptic in shape and alternate on the stems. The stem leaves vary from 2-7 cm long and are 2-8 mm wide with entire to irregulary toothed margins. The blades may also be folded along the midrib.

The inflorescence at first appears as a panicle, but is really a terminal raceme at the end of each branch. The racemes are lax and few-flowered. The flowers are subtended by small, leaf-like bracts. The pedicels are 5-20 mm long while the floral tube is 1-8 mm long. The 4 sepals are each 1-3 mm long. Each of the 4 petals is white or mostly pink, 2-6 mm long and cleft 1/3-1/2 the length of the petal (See photo above.).Stigma is divided into 4 very short, erect lobes. The fruit is a capsule from 1.5-3 cm long. The outer surface of the capsule may be glabrous or slightly glandular hairy.


Varieties of Epilobium paniculatum: Note that these varieties are not currently recognized under the current classification revision to E. brachycarpum.

Variety jucundum: The petals generally rose-colored and are 7-13 mm long. The hypan is 5-12 mm. Found from coastal Washington south to California and east to Idaho.

Variety paniculatum: The petals are light pink and generally less than 7 mm long. The hypan is less than 5 mm. Found from the west coast from British Columbia south to southern California and east to the Dakotas and New Mexico.


Habitat:

Tall annual willowherb is found in dry to moderately moist places in open areas or in thinly wooded forests from the lowlands to moderate elevations.


Range:

Tall annual willowherb is found from southern Canada south along the west coast and intermountain basins to Mexico and east onto the great Plains in North and South Dakota.


Flower and developing fruit of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi) - Close-up sideview of a flower of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi) - Close-up of the maturing fruits of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)

Additional close-ups of the flowers and maturing fruits of tall annual willowherb as seen along FS Road 16 in Logan Valley.........August 20, 2011.

Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)

Tall annual willowherb blooming on the gravel shoulder of Forest Service Road 16 at Summit Prairie, Malheur National Forest..........August 20, 2011. One can also see yellow-staining collomia (Collomia tinctoria) and purple phacelia (Phacelia hastata var. alpina) on the road shoulder.

Close-up of a small portion of the inflorescence of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi) - Close-up of a flower of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)

Additional close-ups of the inflorescence of tall annual willowherb as seen along Forest Service Road #1647 in southeastern Logan Valley, Malheur National Forest.........August 3, 2011.

Fruits of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi) - Inflorescence of Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)

Annual willowherb going to seed and blooming along an access road near the eastern base of Spanish Peak, Ochoco National Forest.........September 25, 2016.

Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi)


Paul Slichter