Indian horse chestnut - Aesculus indica - ‘Sidney Pearce’

Taxonomy.

Kingdom - Plantae

Subkingdom - Tracheobionta

Superdivision - Spermatophyta

Division - Magnoliophyta

Class - Magnoliopsida

Subclass - Rosidae

Order - Sapindales

Family - Hippocastanacae

Genus - Aesculus

Species - indica

The Indian horse chestnut is one of Kew Gardens' Heritage trees and is an interesting tree at Kew as it was planted late, in terms of the ages of Kew’s Heritage Trees, in 1935. It was selected by Sidney Pearce (from whence it gets it’s name) the then Assistant Curator. It was probably a seedling from the Aesculus collection next to the Orangery and is a very strong, broad specimen, fproducing a large quantity of inflourecence, or flowers. It can be found adjacent to the Nash conservatory, close to the Main Gate. There are, strangely, three older trees here, supported by three newer plantings.

This tree can grow to 30m in height and 12m in circumference and was introduced into Britain in 1851 from the Himalayas. It is very similar to the horse chestnut - Aesculus hippocastanum except for the smooth grey-green bark, the seeds or conkers that are wrinkled, smaller and darker, and it is late flowering. The leaves are a bright dark green, with 5-9 long finger-like leaflets, not dissimilar to the sweet chestnut - Castanea sativa. They flower around 6 weeks after other Aesculus species, which makes it very popular to both bees and gardeners alike. The seeds or conkers of Aesculus contain a form of saponin called Aesculin. Like all saponins this is potentially toxic, as it destroys red blood cells (erythrocytes). However it is used in the perfumery trade a great deal , particularly in shampoo and foam bath products. It is also, when extracted and dried, a good acidity indicator, fluorescing blue in an acidic pH under fluorescent light.