難しすぎるよ。
Recently we tend to planting trees even in the cities.
There are two reasons; individual merit and public merit.
First of all, planting tree on the front yard of our house, single tree add the price of it generally 1% of it. And tree leaves shade keep the room cooler. Its help us
Secondly, however climate of city is warmer about 9 degree than suburbs, tree can make cities cooler. Scientists say that shady by tree leaves street can be lower 20 degree than it without them.
For these reasons, promoting tree planting makes a lot of sense.