The ancestral graves are covered with weeds and small trees. How to destroy it and make it never grow again?

How to eradicate the rainy wild trees in long graves? Grass can grow on the grave, and conifers and evergreen trees can be planted on the side. But you can't plant trees indiscriminately, and you can't grow on the graves of your ancestors, which looks unpleasant. Therefore, Tomb-Sweeping Day should be cleared in time, and herbicide weeds and small trees can still die. It needs to be explained here that paraquat, a herbicide, is banned and is not produced in China. However, glyphosate and glyphosate are systemic herbicides, which are generally used in the vigorous growth period of grass, and have better effects in the case of high temperature and large transpiration. Moreover, the height of grass is required to be above 25 cm, and the dose of drugs absorbed by branches and leaves is large, so that the root system dies through the respiration and conduction of grass. The grave tree can't be completely solved by spraying. To solve the problem thoroughly, we should carefully add 1-20 times of water to the original solution, and then inject it into the cortex with drugs at the root diameter, instead of digging trees and cleaning them after death.