There's something called TNT equivalent. In other words, a bomb that is particularly explosive is equal to a certain number of tons of dynamite. This is beca dynamite has a set amount of energy, and so does a ton of it.
https://en.m.wikipedia.org/wiki/TNT_equivalentI didn't know this myself before researching.
TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion. The ton of TNT is a unit of energy defined by convention to be 4.184 gigajoules (1 gigacalorie),[1] which is the approximate energy released in the detonation of a metric ton (1,000 kilograms) of TNT. In other words, for each gram of TNT exploded, 4.184 kilojoules (or 4,184 joules) of energy are released.
They are not carting around literal tons of dynamite. They have an explosive better than dynamite. Why is it not nuclear, you ask? Why must it be nuclear, I respond.
The point being, in all the above tests of power of this new weapon, years passed, and trees are still growing. No radiation turned all life into withered husks. It is simply either high explosive or the result of a chain explosion. They made dure to take a pretty picture for the camera though.