Of interest this week at Beal...

Caucasian Leopardbane orientale Family: the Sunflower family, Also called Leopards Bane, Leopards Bane Daisy, W. J. Beal False Leopards Bane Botanical Garden If you are having trouble with too many leopards roaming your yard, Caucasian Leopardbane could be what you have been looking for. Its name points to the reputation the acquired long ago that it could repel various wild animals. It is even thought to be unappealing to cottontail rabbits. Most who plant this yellow- flowered perennial keep it for its pure yellow mid-spring color. The most vigorous specimens can attain about a meter (3 ft) in height and there are several horticultural varieties. Ours may be seen in bed 40, of the systematic collection.

Caucasian Leopardbane is one of some 26 species in the Doronicum that are distributed across , , and north Africa. is found throughout southeastern Europe, across the Carpathian mountains, and in . All known Doronicum species are yellow-flowered perennials that form vegetative colonies via rhizomes. Their flower heads are typical of the composite habit seen frequently throughout the sunflower family, the Asteraceae (see next page).

The tendency to flower in April or May, then to disappear before the first week of July, makes Doronicum almost qualify as a spring ephemeral. In the perennial flower garden, Doronicum likes moderately moist partially shaded sites, but is tolerant of full sun. In southern localities, it depends on supplemental watering to prevent its burning away into dormancy during the hottest months of summer.

Tazlaciu and Erol (1998) report that Leopards Bane appears in several medieval herbals including its listing as a diuretic, from the above-ground parts, in . In today’s world however, the presence of pyrrolizidine alkaloids make this herb off-limits to internal uses. Left: Caucasian Leopardbane displays the “composite” flower head habit so typical of the sunflower family. Right: In close-up, the petaloid appearance of the ray flowers [bottom] belies the fact that these florets on the edge are sterile. Their role is to attract the attention of an insect pollinator to service the disc florets [top right] that produce the seeds.

Fertile disc flowers

Petaloid appearance of sterile ray flowers

Pyrrolizidine alkaloids occur in a number of plant species within the sunflower (Asteraceae), Bean (Fabaceae), and Borage (Boraginaceae) families. They have been reported to cause intoxication and are present in a number of species formerly used for herbal medicines. It was however, the mutagenic, carcinogenic and liver degrading properties of these alkaloids that have led responsible herbalists to discontinue the advocacy of containing them for internal use. This list of no-longer-advocated herbs includes the well-known use of comfrey [Symphytum officinale]as well as Caucasian Leopardbane.