Fall Weed Seed Germination

Winter annuals - when do they typically germinate and begin growing, i.e. August, September, etc.

 

One grassy weed I'd like to eradicate in one of my fields is sweet vernal grass.  Seems like I read that it actually germinates in the fall????  I don't know much about the life cycle of this weed, but while - an annual, if it starts growing in the fall, it would be great if/when I hit the field with round-up, I could zap it too.

 

Other broadleaf weeds - when do you typically start seeing them?  Planning some fall broadleaf herbicide spraying and want the timing right.

 

Thanks,

Bill

Fall Weed Seed Germination