Ventenata, not just a Rangeland Weed

Ventenata infests millions of acres of rangeland, however, this winter annual grass can also infest your crops and significantly impact yield. Ventenata can out compete downy brome populations, has less nutritive value than most of our winter annual grasses, can cause damage to harvesting equipment and livestock will avoid grazing Ventenata at all times. Ventenata can be differentiated from downy brome by the bent awns and prominent black node in the stem (picture 1-2).

In 2013, Drew Lyon and I performed research trials for the management of Ventenata in cereal crops. Ventenata could be controlled in cereal crops using most Group I and II herbicides, depending on surfactant combination (See data from 2013). We saw similar control at the Thorton, Washington site in 2013-2014. Osprey with AMS and Zidua pre-emergence provided excellent control at this site in 2013-2014.

Ventenata and Bulbous Bluegrass Control in Winter Wheat Following CRP Takeout, Anatone, WA

9-May-13 3-Jun-13 17-Jun-13
Treatment Rate (oz/a) B. bluegrass control (%) Ventenata control (%) B. bluegrass control (%) Ventenata control (%)
PowerFlex 3.5 85 86 89 90
NIS 0.25% v/v
Olympus 0.9 70 15 90 44
NIS 0.25% v/v
Osprey 4.75 80 15 86 56
NIS 0.25% v/v
Axial XL 16.4 89 99 99 96
Hoelon 42.56 25 0 10 5
COC 16
Puma 0.66 5 0 0 1
Discover NG 16 86 94 98 95
MSO 0.25% v/v
Everest 2.0 1 48 18 69 64
NIS 0.25% v/v
Nontreated check 0 0 0 0
   LSD (5%)* 19 24 28 23

Since 2007, I have been working on the control of Ventenata in range and CRP land. Whether Ventenata infests rangeland or crop production ground, the effective herbicides available provide only one season of control. Currently we have another option for Ventenata management on rangeland and CRP land. This fall we will have the herbicide Rejuvra (indaziflam), previously known as Esplanade. This herbicide is in a different group of chemistry (group 29) and provides multiple years of control of Ventenata, medusahead, downy brome and other winter annual grassy weeds in rangeland and CRP land. The optimal timing for application is in the fall pre-emergent to weed emergence and within 2 weeks of a rainfall event.

Control of Ventenata using Rejuvra in CRP Land

Treatment Rate 2016

Ventenata control

2017

Ventenata control

2018

Ventenata control

2019

Ventenata control

Olympus

NIS

1.2 oz/a

0.25% v/v

100 0 0 0
Plateau

NIS

7 oz/a

0.25% v/v

100 0 0 0
Olympus +

Plateau

NIS

1.2 oz/a

7 oz/a

0.25% v/v

100 0 0 0
Rejuvra

NIS

5 oz/a

0.25% v/v

100 100 100 86
Rejuvra

NIS

7 oz/a

0.25% v/v

100 100 100 88
Rejuvra + Olympus

NIS

5 oz/a

1.2 oz/a

0.25% v/v

100 100 100 93
Rejuvra + Olympus

NIS

7 oz/a

1.2 oz/a

0.25% v/v

100 100 100 100
Nontreated Check 0 0 0 0
LSD (5%) 0.93 0 0 33

Please visit the Weed Resources page for information on these weeds and other common weeds in small grains.