No way of telling, depends on the chemical properties of the soil.
roughly 11000 years.
40 years
150
the Leo last around 2165 years.
There have been six leap years in the last 25.
i think it last 5-10 years
They easily last 30 to 40 years, if not longer.
4 years
Depends On Eating Habits.
70 in the last 15 years
To be fossilised it can take anywhere from a few decades to a couple of years.
The tar pits, which yielded many fossilized dinosaur bones many years ago.