The main trees are pedunculate oak, ash and horse chestnut. Hydroxyethylrutosides have been used as an alternative to horse chestnut preparations (venostasin) containing aescin. The square now has a Wallace fountain and is planted with horse chestnut trees. There are multiple rows of horse chestnut trees on both sides of Chestnut Avenue. Other streets are lined with flowering chestnut, horse chestnut and other decorative shade trees. In parks horse chestnut, lime and maple are commonly planted as well. Trees, mainly beech, oak, and horse chestnut, are widespread, giving the town a green characteristic. Quercetin 3,4'-diglucoside, a flavonol glycoside can also be found in horse chestnut seeds. Leucocyanidin, leucodelphinidin and procyanidin A2 can also be found in horse chestnut. Examples include horse chestnut, maples, ackee and lychee. Horse chestnut seed is classified by the FDA as an unsafe herb. Example species are Apple scab ("Venturia inaequalis") and the horse chestnut disease "Guignardia aesculi". The horse chestnut bears superficially similar seeds (conkers), which are not palatable to humans. The most familiar member of the genus worldwide is the common horse chestnut, "Aesculus hippocastanum".