Is it possible to determine the time of death (to the month or year) of a body buried in soil for over 10yrs?

I am writing a novel where a man's body is found in someone's backgarden (ie in the soil). It has been there for over 10 years and one needs to assume that decomposition went ahead as normal in a non openly aerated environment. Is it possible to determine if it has been there for 10 years and 1 month, or in years? is it possible to distinguish between 10 and 11 years, 10 and 13 years or more?
Answer:
Yes, it is possible. First, the investigator must identify the deceased by photographing the maxilla and mandible (jaw bones) and submitting the picture to a crime/forensics lab for possible matches. Crime labs normally have a databases for dental records in which the computer will generate a list of the closest matches and the scientist will narrow down that list by visual comparison. Next, the identity can be further verified by comparing bone samples to radiographs in the deceased's medical records (long bones such as the humerus or femur if they are intact provide the best comparison). For example, bone length, varus and valgus angles, and bony landmarks are measured and compared to the x-rays. Given that this confirms the identity of the deceased, and database searches reveal no death certificate, the investigation continues. Next, the investigator will need an osteologist to analyze the bones. This analysis will reveal the approximate age of the deceased at time of death. This approximation is then added (in years) to the subject's date of birth, which should be found in the medical records. The sum is the approximate year the subject died. If the investigator wants to know the exact month, he must rebury the bones in the same or very similar garden (same soil, same depth) for at least a year in order to compute the rate of decalcification. The decalcification rate (which is stated in micrometers per month) is then divided from the total amount of decalcified bone tissue (in micrometers). The quotient is the number of months that have elapsed since decalcification began (the time of tissue death, given that bone decay was uniformly present). This will narrow down the time of death within one month.
There are many other ways of figuring out the year and/or month of death, but given that at least 10 years had passed since the time of death, the bones and clothing of the deceased would be considered most significant to the investigation.

---

Yes but there need to be clues as to when the body was buried ie: a ticket stub from a theater or an unused ticket for an event or show, a sales receipt ( for cash if the body is to be anonymous at this point) if there is a crime lab involved pollen can be used or perhaps a dead insect on the body or caught in the clothing or hair will help, the clothing itself can provide a clue shorts and short sleeves are one clue a light jacket and jeans are another and a heavy coat is yet another indicator of the time of year the death occurred there are several clever ways that you can use to hide evidence of time of death on a body such as the sales receipt caught in the small pocket of a pair of jeans the change pocket you know the small one on the right front that no one ever checks and few people actually use or in the shirt pocket or perhaps a money belt was worn by the victim or perhaps he had a distinctive dental feature that was altered ie had a mug shot taken in Feb. and had a gold tooth done in march and disappeared in April or broke his arm in may and still has cast in place but the bone is mostly healed that will narrow it down to a few week window combined with other clues this can further pin point the time of death be inventive and the right way to do it for your dead body will make itself apparent.

---