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Sweet JoePye Weed

Eutrochium purpureum (L.) E.E. Lamont

(formerly Eupatorium purpureum L.)

Asteraceae (Sunflower Family)

▲▼ mature flowering plants

▲ head inflorescence clusters

▲ stems and leaves, showing green stems with purple band at the nodes

Eutrochium purpureum (L.) E.E. Lamont., Sweet Joe-Pye Weed (formerly Eupatorium purpureum L.):  (Bayer Code:  EUPPU; US Code EUPE21)

·         U.S.  native simple perennial with usually solid, green (may be purple at nodes) generally hairless stems that can grow 2-7 feet tall; stem branching mainly in upper part of stems as flowering commences

·         Leaves are in whorls of 4-5 at nodes, lanceolate, with toothed margins

·         Head inflorescences are born in panicles at tips of stems; stems in inflorescence are covered with soft hairs

·         Individual flower heads are about 0.25 inch diameter, with 4-6 lilac to dusty-pink to almost white disk flowers (no ray flowers); flowers may open a lighter color, becoming more purple-pink as they mature

·         Bracts below inflorescence are in multiple layers, oval, greenish-white to pink, hairy; tips are round-pointed

·         Flowering time is from mid-summer to early fall

·         Prefers moist, fertile soils in meadows, pastures, open, streambanks

·         May be toxic if overgrazed, but a favorite of butterflies

·         Similar species include:

     o   Hollow-stemmed Joe-Pye Weed (Eutrochium fistulosum) has hollow, usually hairless stems, and large, open panicle inflorescences; flower heads have 5-7 disk flowers

     o   Spotted Joe-Pye Weed (Eutrochium maculatum) has mostly solid stems, but flowers heads are more flattened, leaves a lighter green and flower heads have 8-20 disk flowers

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