Cercis siliquastrum

Flowers sprouting from old growth

blooming branch with flower cross sections

Trunk and bark

This species forms a small tree up to 12 m (39 ft) in height and 10 m (32 ft) in width.[2]

The deep pink flowers are produced on year-old or older growth, including the trunk, in spring. They have five free petals and fused sepals, a flower shape typical of much of the pea family (Fabaceae). The leaves appear shortly after the first flowers emerge. These are cordate with a blunt apex and occasionally have a shallow notch at the tip. The tree produces long flat pods that hang vertically. The flowers are edible and reportedly have a sweet and tart taste.[2]

A botanical illustration from 1891

The species was first described by Linnaeus in 1753 and he gave it the specific epithet of siliquastrum which is derived from the Latin word siliqua, meaning "pod".[3] The generic name comes from the Greek kerkis, a "shuttle", which refers to the resemblance shown to this weaver's tool by the flat, woody seedpods.[4]

There are several varieties and subspecies including:-

• var. hebecarpa Bornm.
• nothosubsp. yaltikirii (Ponert) Govaerts
• var. siliquastrum
• var. alba Weston

Flowers and pods

Cercis siliquastrum - MHNT

The cultivar 'Alba'

Psyllids (Cacopsylla pulchella) on a leaf

The pods are first green and then turn brown-red.

The flowers are pollinated by bees, which are attracted by nectar. Pollen from the protruding stamens is deposited on the bee's body and carried to another flower's stigma.[5]

In Israel the tree has a status of a protected plant.

British journalist Francis McCullagh reported seeing "innumerable" flowering specimens of this tree in Yildiz Park in Istanbul in April 1909.[6]

The species prefers deep, well-drained soils and a position in full sun or partial shade.[2]

Cultivars include:

• 'Afghan Deep Purple'[7]
• 'Alba' - white flowers[7]
• 'Bodnant'[7]
• 'Carnea'[7]
• 'Fructa Rubra'[7]
• 'Penduliflora'[7]
• 'Rubra' - dark pink-purple flowers
• 'Sterilis'[7]
• 'Variegata'[7]
• 'White Swan'[7]

The cultivar 'Bodnant' has gained the Royal Horticultural Society's Award of Garden Merit.[8] (confirmed 2017).[9]

The tree is susceptible to leafhoppers, scale insects and psyllids (specifically Cacopsylla pulchella) as well as diseases including canker, coral spot and verticillium wilt.

Propagation is by seed, cuttings or budding.

The species produces hard wood with an attractive grain. It is used in veneers and polishes well.[2]

There is a myth that Judas Iscariot hanged himself from a tree of this species, causing its white flowers to turn red.[10] This belief is related to the common name "Judas tree", which is possibly a corrupted derivation from the French common name, Arbre de Judée, meaning tree of Judea, referring to the hilly regions of that country where the tree used to be common.[11] Another possible source for the vernacular name is the fact that the flowers and seedpods can dangle directly from the trunk in a way reminiscent of Judas's possible method of suicide.[4]

A sermon illustration on the deadly effects of succumbing to temptation refers to a false idea that the Judas tree killed bees drawn to it: "Dr. Cuyler forcibly illustrates this by reference to the Judas tree. The blossoms appear before the leaves, and they are of a brilliant crimson. The flaming beauty of the flowers attracts innumerable insects; and the wandering bee is drawn after it to gather honey. But every bee which alights upon the blossom, imbibes a fatal opiate, and drops dead from among the crimson flowers to the earth."[12]

Judas trees in Istanbul, Turkey, especially the Bosphorus, give their distinctive purple color in spring. It is one of the important images of Byzantium and Christianity. The purple of the Judas tree flower resembles the color used in the clothes of Byzantine rulers. It was a sign of wealth and power, as it was the most difficult color to be produced naturally. Except for the emperor, no one could wear the color purple.[13]

Judas trees have been the symbol of Bursa, Turkey for centuries. "Erguvan (redbud) festivals" started to be organized since the 14th century because Emir Sultan, one of the Muslim Anatolian saints, son-in-law of the Ottoman Empire sultan Bayezid I, met with his followers in Bursa every year during the Judas tree blooming season, continued as a tradition until the 19th century due to their positive effects on the city's economy. There is a present effort to revive these festivities.

The Judas tree is referred to as a traditional Palestinian medicinal plant.[14]

• International Legume Database & Information Service (ILDIS): Cercis siliquastrum
• The Royal Horticultural Society : Circus siliquastrum
• Wildflowers of Israel : Judas tree
• Media related to Cercis siliquastrum at Wikimedia Commons