1- Are only mahrams allowed to carry a female when burying her?
2- Is it lawful or unlawful to plant trees by gravesides? Please note that the road is two meters wide and the trees planted are of the Ficus genus.
3- Is it permissible for people to enter upon a deceased without ablution during the process of washing?
4- Is it permissible to bury males and females together in a single grave?
5- Before his death, a person directed that a particular person is not to follow his funeral procession or attend the condolences gathering. Is it obligatory to execute his directive?

1- When it comes to burial, the male mahrams (non-marriageable kin), particularly the husband, of a deceased female take precedence over others. If none is available, or if available but cannot perform the task properly, a righteous non-mahram undertakes the task.

Allah the Almighty knows best.

2- It is permissible to plant trees by gravesides provided they do not obstruct the path of those following the funeral procession or those undertaking burial. Otherwise, it is impermissible. The planted trees must not be of the kind that have divaricating root structure. The roots must be vertically oriented so as not to destroy or harm the graves.

Allah the Almighty knows best.

3- It is permissible for a person to enter upon a deceased without ablution during, before or after washing the deceased. Allah the Almighty knows best.
4- It is impermissible to bury women and men in the same grave except in cases of extreme necessity. If this is truly necessary, a barrier of earth must be put between a man and a woman; the man is to be buried at the front of the grave and the woman at the back. Allah the Almighty knows best.
5- Such a will is not to be implemented. A person is not to prevent another from following his funeral procession or from performing the funeral prayer over him.

Allah the Almighty knows best.