■ 栃の木 (the tree)
■ 栃木 (city and prefecture)
■ 栃の木 Aesculus Turbinata, the Japanese horse chestnut tree
A deciduous tree, very similar to the European horse chestnut, A. hippocastanum, native to all of mainland Japan, and also common as a planted tree on avenues. Bears fruit in cases which lack the spines of its European relative. The fruit, 栃の実（とちのみ）, may be poisonous if eaten raw, but can be treated and used as a source of food, including delicacies such as 栃餅（とちもち）. Most of the American species of Aesculus bear the name "buckeye", and this is also sometimes used as a translation of 栃の木.
More general information may be found in my photo essay
■ 栃木 City and prefecture of Tochigi
The prefecture, 栃木県（とちぎけん） extends from the northern edge of the Kanto Plain up into the mountainous backbone of Honshu, and is (though this fact is seldom remarked on) easily the most circular prefecture. The city, 栃木市（とちぎし） lies at the southern extremity of the prefecture near the northern edge of the Kanto plain. Utsonomiya is the 県庁所在地（けんちょうしょざいち） or "seat of prefectural government" (corresponding to a county town in the UK or state capital in the USA).
■ マロニエ Horse chestnut (strictly, the European species)
This is from the French marronnier for "horse chestnut", and katakana dictionaries typically define it as referring to the European horse chestnut. However, it is typically used as a fashionable name, particularly within Tochigi, implying an association with the Japanese variety. The romanisation is highly variable, but searches at goo.ne.jp suggest that "Maronie" heavily outnumbers "Marronnier".
Maronie.net - a Tochigi-based web hosting service
Maronie Puraza - a typical web page for an exhibition centre in Utsunomiya, featuring a horse chestnut leaf emblem. (It seems unlikely that the species could be identified from this drawing!) Their romanisation is not clear, except for the URL www.pto.co.jp/maronie/.
Chalet Marronnier - somewhere using the original spelling, though only in the web page title
This entry was created by Brian Chandler.