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A New Publication: Advances in Dryland Farming in the Inland Pacific Northwest

A rainy sunset over the Palouse.
The newly published book, Advances in Dryland Farming in the Inland Pacific Northwest, compiles advanced knowledge of dryland farming gained during the six-year Regional Approaches to Climate Change (REACCH) project. This book is an excellent guide to sustainable agriculture practices. The aim of this book is to support farmers during their decision-making process and to enhance… » More ...

“Where We Are with Wireworms” Podcast

Paperboy_1400-300x300Recently, Aaron Esser was interviewed by Scott Yates, director of communications at the Washington Grain Commission for an update on wireworms. In episode 26 of the Wheat All About It! podcast, Esser talks about where we were and where we are today thanks to the great strides WSU researchers have made in understanding and controlling wireworms in Eastern Washington.

Listen to episode 26, Where We Are with Wireworms, and don’t forget to subscribe to the Wheat All About It! podcast on iTunes. Search for Wheat All About It. A summary of podcasts, including many highlighting WSU researchers is available at the WGC website:

For questions or comments, contact Aaron Esser by email at or Scott Yates at

Proper Sprayer Cleanout Can Prevent Crop Injury

A stripe of peas that have herbicide injury.
The strip of winter peas in the middle of this picture were sprayed with Clethodim 2 EC, but the observed injury was from the previous products in the sprayer: Huskie + Osprey. A water rinse is never adequate when using a tank-cleaning herbicide like clethodim. This injury could have been avoided by carefully cleaning the sprayer before switching from spraying wheat to spraying peas.
The strip of winter peas in the middle of this picture were sprayed with Clethodim 2 EC, but the observed injury was from the previous products in the sprayer: Huskie + Osprey. A water rinse is never adequate when using a tank-cleaning herbicide like clethodim. This injury could have been avoided by carefully cleaning the sprayer before switching from spraying wheat to spraying peas.

We have received a number of phone calls recently concerning crop damage in peas treated with herbicides containing the active ingredient clethodim. Clethodim is an ACCase inhibitor (Group 1) used to control grass weeds in broadleaf crops. There is no clethodim activity on broadleaf crops like peas. So why is there sometimes injury to peas?

Clethodim products containing 26.4% or 2 pounds of clethodim per gallon (for example, Arrow 2 EC, Clethodim 2 EC, and Select 2 EC) contain as much as 70% petroleum distillates. This high level of petroleum distillates, combined with the required crop oil concentrate and liquid fertilizer additives, can act as a sprayer cleaner, dislodging old herbicide residues that are embedded in tank walls or hoses, resulting in unwanted herbicide residue in the sprayer liquid. It is these residues, and not the clethodim, that are injuring the peas.

This type of damage, which is not unique to clethodim products, can be avoided by properly cleaning sprayers between applications, particularly when changing what crop is being treated. While proper sprayer cleanouts are time-consuming, it can save a lot of money and misery. Removing Herbicide Residues from Agricultural Application Equipment is an excellent publication by Purdue Extension that can help you do a good job of sprayer cleanout and possibly save you headaches and dollars down the road.

For questions, contact Drew Lyon (509-335-2961 or or Ian Burke (509-335-2858 or

Stripe Rust Update – June 2017

Stripe Rust Update June 16, 2017

Xianming Chen

  1. Wheat Stripe Rust

In the Pacific Northwest, winter wheat in most areas has passed the flowering stage.  Thanks to planting of resistant varieties and widely use of fungicides in the early season with some fields sprayed twice, stripe rust in most fields of winter wheat is under control.  Depending upon areas and various times of planting, spring wheat crop varies from Feekes 4 to Feekes 10.5.3.  Stripe rust has developed rapidly in spring wheat fields with severity on susceptible varieties ranging from 5% to 100% depending upon area and planting date.

Because the cooler weather and good moisture in this week, stripe rust will likely develop more in the next couple of weeks. For fields of moderate susceptible and susceptible varieties (stripe rust ratings 5 – 9) of winter wheat, fungicide application is needed if the crop has not passed Feekes 10.5 and fungicide was applied more than two weeks ago.  For spring wheat, fungicide is needed at the time of herbicide application for fields planted with moderately susceptible and susceptible varieties if not done so.  For fields of fungicide applied about three weeks ago, another application is needed.  For varieties previously reported to be resistant to moderately resistant (ratings 1-4), check fields and consider fungicide application if active rust pustules are seen and severity reaches 5%.

We took stripe rust notes in our experimental fields of spring wheat on June 15, most plants passed the flowering stage and the susceptible check had 100% severity. Table 1 shows the data and ratings for the spring wheat variety trials for reference.  As these data were from only Lind and rust races can be different in different areas, use these data together with the data from the last year for considering to use or not to use fungicides.

Since the last report on May 19, wheat stripe rust has been reported in South Dakota, Minnesota, North Dakota, and New York in addition to the previous reports in Texas, Louisiana, Arkansas, Mississippi, North Carolina, Oklahoma, Kansas, Washington, Oregon, Wisconsin, Virginia, Delaware, Tennessee, Michigan, Kentucky, Nebraska, Indiana, Georgia, Idaho, Arizona, California, Montana, and Colorado.  Wheat stripe rust has been reported in Alberta, Ontario, and Manitoba provinces of Canada.

  1. Barley stripe rust

In our spring crop nurseries at Lind (Adams County, WA), stripe rust was uniform on susceptible varieties with severity up to 40%.  For this dryland area, this is the most severe barley stripe rust we have seen in the last 20 years, partially due to the 6-inch higher-than-average precipitation this year, although much lower than wheat stripe rust in this location.  Barley stripe rust has not been observed in the Palouse region yet.  In addition to Washington, barley stripe rust has been reported in California and Oregon.

Fungicide application may be needed to control barley stripe rust this year.  Check barley fields for stripe rust, if severity reaches 5%, apply fungicide.  The fungicides that control wheat stripe rust also control barley stripe rust.

Table 1.  Stripe rust data of the 2017 WSU Spring Wheat Variety Trials at Lind, WA*

      Lind, WA  
    2017 Feekes 10.5.3  
Name v_desc Plot # IT % Rating
14-FAC-2043 SWS 1 2 15 2
14-SW-1030 SWS 2 2 15 2
14-SW-1059 SWS 3 2 15 2
SY Saltese (SY 04PN3024-2) SWS 4 2 15 2
IDO1403S SWS 5 2 2 1
WB-1035CL+ SWSI 6 8 90 9
WB6121 SWS 7 2 10 2
WB6341 SWS 8 3 25 3
WB6430 SWS 9 3 20 3
Babe SWS 10 8 80 8
Diva SWS 11 2 15 2
JD SC 12 2 15 2
Louise SWS 13 3 15 2
Melba SC 14 2 10 2
Ryan (WA 8214) SWS 15 3 20 3
Seahawk SWS 16 2 2 1
Tekoa (WA 8189) SWS 17 2 10 2
WA 8236 CL+ SCI 18 2 5 1
WA 8265 CL+ SWSI 19 5 30 4
WA 8266 CL+ SWSI 20 5 30 4
AvS (Susceptible check)   21 8 100 9
WA 8277 SWS 22 2 10 2
WA 8278 SWS 23 5 30 4
Whit SWS 24 3 20 3
YS-603 SWS 25 2 10 2
14-FAC-2019   26 3 20 3
500-709 HRS 27 2 2 1
501-089 HRS 28 2 2 1
12SB0197 HRS 29 2 5 1
12SB0199 HRS 30 2 5 1
12SB0224 HRS 31 2 10 2
LCS Iron (11SB0096) HRS 32 2 15 2
LCS Luna (10SB0087-B) HRS 33 2 10 2
LCS Buck Pronto HRS 34 7 30 6
06PN3017-09 HRS 35 2,8 5,40 3
SY 06PN3015-08 HRS 36 2 2 1
SY Coho (04W40292R) HRS 37 2 5 1
SY Selway (04PN3001-2) HRS 38 2 10 2
SY Steelhead HRS 39 2 15 2
SY605 CL HRSI 40 8 40 7
AvS (Susceptible check)   41 8 100 9
IDO1603S HRS 42 2 5 1
WB9200 HRS 43 2 2 1
WB9229 HRS 44 2 2 1
WB9350 HRS 45 2 2 1
WB9411 HRS 46 2 10 2
WB9518 HRS 47 2 2 1
WB9662 HRS 48 2 5 1
WB9668 HRS 49 2 5 1
XA9861 HRS 50 2 2 1
Alum HRS 51 2 10 2
Chet HRS 52 2 10 2
Glee HRS 53 2 10 2
Hollis HRS 54 5 30 4
Kelse HRS 55 5 40 4
WA 8259 HRS 56 3 20 3
WA 8261 HRS 57 3 20 3
WA 8279 CL+ HRSI 58 3 20 3
WA 8280 CL+ HRSI 59 3 15 2
WA 8281 HRS 60 2 10 2
AvS (Susceptible check)   61 8 100 9
WA 8282 HRS 62 3 15 2
WQL17SSV16882-3 Durum 63 2/7 5/50 3
WQL18SALZ-3 Durum 64 2/5 5/40 3
SY Basalt HRS 65 2 5 1
WA 8263 HWS 66 3 30 3
WA 8283 HRS 67 2 5 1
WA 8284 HRS 68 3 15 2
WA 8285 HRS 69 2 2 1
Dayn HWS 70 2 5 1

* IT = infection type; % = severity based on infected leaf areas; and ratings are in a 1-9 scale with 1 for most resistant and 9 for most susceptible.

View the June 2017 Stripe Rust Update in PDF format.

New Bulletin Published on the Wheat Head Armyworm Complex

A newly published Extension Bulletin, PNW696, is titled “Integrated Pest Management for the Wheat Head Armyworm Complex in the Pacific Northwest.”

Since 2005, the wheat head armyworm has caused intermittent damage to wheat and barley crops in the PNW.

The two insect species found responsible were initially dubbed the “true” and “false” wheat head armyworms. As these species are closely related, we now refer to them as the wheat head armyworm complex (WHAC).

This publication covers identification, biology, and integrated pest management for WHAC. We emphasize pest monitoring and field scouting methods, and also discuss natural insecticides.

Authors are Diana Roberts, WSU Extension; Silvia I. Rondon, OSU Extension; Peter J. Landolt, USDA-ARS.

Don’t Worry About LMA and FN Yet

In 2016, Washington state wheat farmers experienced widespread problems with low Falling Numbers, for which we created our Grain Quality Resources page. The widespread low Falling Number issue was partly due to Late Maturity Alpha-Amylase (LMA) in response to wildly fluctuating temperatures about one month after pollen shedding. The high temperatures in the 90s on May 30 followed by high temperatures in the 60s has some farmers worried that we’re going to see a repeat of last year’s Falling Number fiasco. Such worries are premature because the wheat hasn’t yet reached the point where it is sensitive to fluctuating temperatures.

It is difficult to pinpoint the window of LMA-sensitivity for this year’s crop because it depends on when the wheat reached pollen-shedding, an event that depends on temperature and varies by variety. Wheat in central Washington reached pollen-shedding during the week following Memorial Day, while wheat further east is just starting to head.

Based on this, we guesstimate that wheat in central Washington may become LMA-sensitive during the last two weeks of June, while wheat further to the east may become LMA-sensitive within the first two weeks of July.

For questions or comments, contact Camille Steber, PhD, USDA-ARS, Molecular Geneticist, by email at or Ryan Higginbotham at

Washington State University