Weeds persist for many years.
They negatively impact human activities and as such are undesirable. 100 weeds committed to memory will make you the local weed identification expert. You will be held responsible for about 75 species in the laboratory of this course. Weed seeds survive freezing, drought, submersion in water, burial in soil and passage through animal digestive tracts. When all conditions for germination are present and alive seed remains inactive, it is termed dormant.