I have been to several farm calls in the past few weeks with this weed (pictured below). I have seen 7 fields between last year and this year that appear to have bad infestations of this new watergrass species (Echinochloa spp.). We are unsure of the exact identification yet, but we know it is in the watergrass family.

The weed is maturing around mid- to late-July. It is small-seeded, and the awns are long and purple. All of the plants I have seen so far have seed heads that are completely awned, which makes it different than barnyardgrass (which has seed heads that are variably-awned).

How to ID:

o   Every seed head has awns (unlike barnyardgrass)

o   Should already be headed (by mid- to late-July)

o   Awns are purplish in color (see photos)

o   Seeds are small (smaller than late watergrass)

Please call Whitney Brim-Deforest (541-292-1553) or Luis Espino (530-635-6234), if you suspect that you have this weed in your field. We would like to collect seed samples to see what can be done to control it. 

Photo 1. Seed head of unknown watergrass species (Echinochloa spp.) Notice visible purple awns.

Photo 2. Seed heads of unknown watergrass species (Echinochloa spp.) Notice visible purple awns, which can be seed before seeds are fully mature.

Photo 3. Full plant sample of unknown watergrass species (Echinochloa spp.). This plant headed in late July.