Is there any group that looks after the conservation of trees and advises people before a cyclone comes ?

There is little that can be done in the short term to protect trees from cyclones (or hurricanes as we call them in North America). The best measure to protect inland trees is to plant more trees in coastal areas. Mangroves and coastal forests provide the best protection against storm surges. Mangroves are very effective buffers against cyclones. Mangrove tree species have evolved to withstand strong wind and waves. Unfortunately, many mangroves have been extensively destroyed in recent decades. Conservation of mangroves and coastal forests is a good long term strategy to protect forests further inland. There are a number of conservation groups working on mangrove restoration in various countries. Overall, the damage of mangroves for agriculture and aquaculture is continuing on most tropical coastlines.

There are several government websites which provide information on how to prepare for cyclones (the governments of Australia and India for example). There are very few resources which recommend ways to protect trees and vegetation. Most of the concern is for human life.

http://news.mongabay.com/2009/0415-hance_orissacyc...

http://www.scidev.net/en/agriculture-and-environme...