Tall Boneset often competes directly with Solidago canadensis (Canada Goldenrod) in disturbed areas, although it prefers slightly drier areas. The two plants appear similar to each other prior to bloom, although the former has darker leaves. This plant provides some white color to a fall landscape that is often dominated by forbs with yellow flowers and the brown color of dried-out grasses. This is the easiest boneset to grow in dry sunny areas. Some people may mistake this plant for a weed, which it is to some extent.

This native perennial plant is 3-4' tall and unbranched, except for the upper flowering stems. The stems are covered with white hairs. The opposite leaves are up to 5" long and 1" across, occasionally with small teeth along the margins. They are usually dark green, lanceolate to narrowly ovate, and pubescent. There are three conspicuous veins that run along the length of each leaf. The rather flat inflorescence consists of numerous heads of small white flowers and their buds. These flowers are dull white and individually only 1/8" across. There is little or no floral scent. The blooming period occurs from late summer to early fall, and lasts about 1-1½ months. The achenes develop small tufts of white or light brown hair; they are dispersed by the wind. This plant may spread vegetatively through rhizomes.

Eupatorium altissimum L.:
United States (North America)

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Tall Boneset occurs in most of Illinois, except some southern counties (see Distribution Map). It is a common plant. Habitats include mesic to slightly dry black soil prairies, clay prairies, gravel prairies, savannas, thickets, openings in upland forests, dry banks of lakes, limestone glades, pastures and abandoned fields, fence rows, vacant lots, and areas along railroads. This plant favors disturbed areas, where it may form large colonies.

Eupatorium altissimum occurs in sexual diploid populations in the Ozark region of Missouri and Arkansas, and as apomictic polyploids elsewhere throughout its range. It occurs almost exclusively on limestone soils, where it is often accompanied by (and sometimes misidentified as) Brickellia eupatorioides, which has 10-ribbed cypselae and plumose pappus bristles. Eupatorium altissimum hybridizes with E. serotinum.

Perennials, 50–150+ cm. Stems (from short caudices or stout rhizomes) single, sparsely branched distally, pubescent throughout (nodes sometimes with galls). Leaves usually opposite (nodes often appearing leafy, lateral buds producing 2+ pairs of leaves); sessile or subsessile; blades strongly 3-nerved from bases, lance-elliptic to oblanceolate, 50–120 × 5–20 mm, bases ± cuneate, margins entire proximally, serrate distally, apices acuminate, faces puberulent or villous, gland-dotted. Heads in corymbiform arrays. Phyllaries 8–10 in 2–3 series, oblong, 1–4 × 0.5–1.5 mm, (bases tapered) apices rounded to acute (not mucronate), abaxial faces pubescent throughout. Florets 5; corollas 3–3.5 mm. Cypselae 2–3 mm; pappi of 30–40 bristles 3.5–4 mm. 2n = 20, 30, 40.

Tall Boneset occurs in most of Illinois, except some southern counties (see Distribution Map). It is a common plant. Habitats include mesic to slightly dry black soil prairies, clay prairies, gravel prairies, savannas, thickets, openings in upland forests, dry banks of lakes, limestone glades, pastures and abandoned fields, fence rows, vacant lots, and areas along railroads. This plant favors disturbed areas, where it may form large colonies.

Eupatorium altissimum (Tall Boneset)
(All insects suck nectar; most observations are from Robertson, otherwise they are from Hilty as indicated below)

Bees (long-tongued)
Apidae (Apinae): Apis mellifera (Rb, H) fq; Apidae (Bombini): Bombus fraternus, Bombus impatiens, Bombus pensylvanica; Anthophoridae (Ceratinini): Ceratina dupla dupla; Anthophoridae (Epeolini): Triepeolus donatus, Triepeolus pectoralis fq; Anthophoridae (Eucerini): Melissodes rustica fq; Anthophoridae (Nomadini): Nomada vicina vicina fq; Anthophoridae (Xylocopini): Xylocopa virginica (H)

Bees (short-tongued)
Halictidae (Halictinae): Augochlorella aurata, Augochloropsis metallica metallica, Halictus confusus, Halictus ligatus, Lasioglossum illinoensis, Lasioglossum imitatus, Lasioglossum versatus, Lasioglossum zephyrus; Colletidae (Colletinae): Colletes americana; Colletidae (Hylaeinae): Hylaeus affinis; Andrenindae (Andreninae): Andrena asteris fq; Andrenindae (Panurginae): Perdita octomaculatus

Wasps
Sphecidae (Bembicinae): Bicyrtes ventralis, Stizus brevipennis; Sphecidae (Crabroninae): Ectemnius dilectus, Oxybelus packardii; Sphecidae (Larrinae): Ancistromma distincta fq; Sphecidae (Philanthinae): Eucerceris zonata, Philanthus ventilabris; Sphecidae (Sphecinae): Ammophila nigricans fq, Ammophila procera, Isodontia apicalis; Vespidae: Polistes annularis, Polistes fuscata; Vespidae (Eumeninae): Ancistrocerus adiabatus, Ancistrocerus campestris, Eumenes fraterna, Euodynerus foraminatus, Zethus spinipes; Sapygidae: Sapyga interrupta; Tiphiidae: Myzinum quinquecincta; Pompilidae: Anoplius lepidus, Entypus fulvicornis; Chrysididae: Hedychrum wiltii; Ichneumonidae: Ceratogastra ornata

Flies
Syrphidae: Milesia virginiensis, Spilomyia longicornis, Syritta pipiens; Empidae: Empis clausa; Bombyliidae: Exoprosopa fasciata, Sparnopolius confusus, Toxophora amphitea, Villa hypomelas; Conopidae: Physoconops brachyrhynchus, Thecophora occidensis; Tachinidae: Archytas analis, Archytas aterrima, Gnadochaeta globosa, Gymnoclytia immaculata, Leskiomima secunda (Rb, MS), Linnaemya comta, Phasia fumosa, Phorantha asteris (Rb, MS), Spallanzania hesperidarum; Sarcophagidae: Sphixapata trilineata; Muscidae: Graphomya americana, Morellia micans, Neomyia cornicina; Calliphoridae: Cochliomyia macellaria

Butterflies
Nymphalidae: Chlosyne nycteis, Danaus plexippus (H), Euphydryas phaeton, Junonia coenia (H), Libytheana carinenta (H), Phyciodes tharos; Pieridae: Colias eurytheme (H), Pontia protodice

Skippers
Hesperiidae: Polites peckius (Rb, H), Polites themistocles

Moths
Ctenuchidae: Cisseps fulvicollis; Noctuidae: Helicoverpa zea (H); Yponomoutidae: Attera punctella (H)

Beetles
Cantharidae: Chauliognathus pennsylvanicus (H)

Plant Bugs
Miridae: Lygus lineolaris fq

The nectar of the flowers attracts many kinds of insects, including long-tongued bees, short-tongued bees, wasps, flies, small butterflies, skippers, beetles, and plant bugs. Among these, wasps and flies are particularly common visitors. The wasp visitors include Paper wasps, Thread-Waisted wasps, bee wolves (Philanthus spp.), Scoliid wasps, Larrine wasps, Sand wasps, Spider wasps, and others. Fly visitors include Syrphid flies, bee flies, Tachinid flies, Muscid flies, and others. The caterpillars of several moths feed on various parts of Tall Boneset and closely related plants, including Haploa clymene (Clymene Moth), Phragmatobia lineata (Lined Ruby Tiger Moth), Carmenta bassiformis (Eupatorium Borer Moth; bores into roots), and Schinia trifascia (Three-Lined Flower Moth; eats flowers & seed capsules). Mammalian herbivores, including livestock, shun the bitter-tasting leaves of this plant; consequently, it tends to flourish in pastures.

Canada

Rounded National Status Rank: N1 - Critically Imperiled

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

The preference is full or partial sun, and mesic to dry conditions. The soil can contain significant amounts of loam, clay, or gravel; soil with a high pH is tolerated. Drought tolerance is good, although the plant may wilt. Tall Boneset is very easy to grow, and competes well against other plants. It is usually not affected by foliar disease.