|Porter aster, a late-blooming native plant|
There is another less-friendly white daisy that is also blooming right now that some people confuse with Porter aster – this is the State List B noxious weed called Scentless chamomile (Matricaria perforata or Tripleurospermum inodorum). This weed is rapidly increasing in population in our mountain counties, forming monocultures in places like Winter Park, Fraser, Nederland, and many other locations. The reason it can spread so fast is that in a single year, one plant can produce up to 300,000 seeds! http://www.colorado.gov/cs/Satellite/ag_Conservation/CBON/1251621067095. I swear that it often seems as though each one of those seeds germinates and becomes a plant. Yikes! Please remove it from your property if you have it – and the task will be MUCH easier if you do it early in the game, before the exponential explosion occurs.