「Tree capital」is its FRUIT, containing 'seed capital' for starting new growth, an English term still in use today, but also refers to a first-rate or an excellent idea. FRUIT is defined as the sweet and fleshy meat of a tree that bears seeds, the offspring of animals, the results or consequences of an action or effort:「woody and palming head with stream of emissions down from orifice」that enables a male to PROPAGATE WELL by clearing his system of older, less motile and less spunky seeds.
　Variety of ELM that PROPAGATES WELL just about everywhere, places that naturally may not have been conducive to growth, so that elms were planted where other species of trees had failed to take root. The ELM tree was recommended for planting beside boulevards in large cities (capitals?) due to its resistance to polluted air, polluted soil, and the harsh conditions generally extant in large cities and capitals caused by the overconcentration of human beings in confined spaces living in heaped up man-made piles of dirt: nevertheless, in most U.S. municipalities today, it is illegal to plant an elm tree on city property due to the mess it creates. One particularly bothersome characteristic of ELM trees is the vast number of seeds each tree produces, often forming huge swirling drifts or large pools of seeds, PROPAGATING WELL.
　The grey STARLING, a highly gregarious bird that perches in「trees of the capital cities」forming huge murmurs (a starling flock of closely-crowded birds) also PROPAGATES WELL, and most often include various species and plenty of excrement, as do human beings who dwell in a large metropolis or capital city. Birds and other animals spread the seeds they have eaten by excreting in places other than where the fruit and seeds were swallowed.

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: see 椋鳥|椋鸟
Japanese: Aphananthe oriental elm, mukutree
Unihan extended: fruit
EDRDG: type of deciduous tree; grey starling

Used within names (nanori)
ぐら