British Columbia: Safety of Herbicides

In my Village we are slowly clearing out himalayan blackberry, english ivy, scotch broom, chinese lonicera, couch grass, morning glory ..... from an area (about a fifth of an acre) that is to become a Native Plant Garden, with plants specifically indigenous to our immediate region. Although we wish to avoid the use of herbicides, we are finding that the labour intensive digging-out of invasives and weeds is quite taxing. What information and research references are available about the safety of herbicides, their specificity, their resistance to degradation in the soil, etc, that would be of assistance to us? Thank you in anticipation. Louis.

 

Though from the United States, so not entirely applicable to a situation in Canada, you can start by investigating the US National Pesticide Information Center, a cooperative venture between the EPA and Oregon State University.