Question
one of my neighbours has a tree in their front yard that produces these little green olive looking things and when crushed give off the most foul smell i've ever experienced.
their small, definitly no bigger than an inch long,
kinda bright, green coloured,
gives off the smell of vomit and fecal matter.
this tree is in ontario
but i do not know if its a native speicies as i've never encountered one before.
could you please tell me what this trees name is and what are the 'olives' really are ?

thanks for the help

Answer
This is a tree called Ginkgo. The ginkgo tree, or Ginkgo biloba, is sometimes known as the maidenhair tree.It is one of the tree species that have separate male and female trees. Yours unfortunately is a female--bearing fruit.

To identify a ginkgo tree, look for fan-shaped leaves, which turn a golden yellow color in the fall. While it does produce flowers, they are so small as to be unnoticeable to the casual observer. The female tree produces a small, tan-colored fruit that has an objectionable odor. Most horticulturalists and landscapers avoid planting the female ginkgo tree for this reason.

The fruit of the ginkgo tree are plum-like. The pulpy outer layer surrounds a light brown shell in which the cream colored meat is found. The nut has a high starch content and is low in fat. These nuts are widely used in Asian cookery.
Here is a web link to more information on Ginkgo trees, http://www.gardenguides.com/91996-ginkgo-tree.html