This annual with finely divided leaves is also known asa mayweed. Even though it has attractive daisy like flowers, crushed leaves give off a very strong disagreeable odor. Its acrid internal fluids are also known to have caused blisters on those who have pulled or handled the plant. Dog fennel is most often confused with pine-apple weed, which has a very pleasing aroma. Flowers of dog fennel have large white ray petals with centers of bright yellow. This plant, like so many other turf weeds, has the unique ability to avoid damage by a mower.