Progress 08/01/06 to 07/31/10

Outputs
OUTPUTS: We have examined the biology, ecology, and management of Russian thistle, jointed goatgrass, and downy brome throughout diverse regions of the wheat production areas of the PNW. Studies included growth and development, weed/crop interference, and weed seed production. We conducted a 9-yr Integrated Pest Management Project in the high-rainfall zone that examined the effect of two tillage systems, three weed management levels, and two crop rotations on erosion control, crop yield, pest incidence, and farm profitability. The study was multi/interdisciplinary and consisted of 10 to 12 scientists from eight disciplines representing three universities and several state and federal agencies. We conducted an 8-yr continuous no-till spring cropping system study in an 11-inch rainfall zone to supplement or replace the highly erosive, pest infested traditional winter wheat-summer fallow system. This study was also multi/interdisciplinary and involved agronomists, soil scientists, pathologists, entomologists, weed scientists, economists, and rural sociologists. Several new systems were evaluated and included planting facultative spring wheat into chemical fallow. A three-state integrated cropping systems study for the management of jointed goatgrass was started in 1996 in the traditional winter wheat-fallow region of the PNW. The study evaluated eight integrated weed management (IWM) systems that included combinations of either a one-time stubble burn or a no-burn treatment, a rotation of either winter wheat-fallow-winter wheat or spring wheat-fallow-winter wheat and either a standard or integrated practice for planting winter wheat. Integrated planting practices included planting a competitive variety, increased seeding rates and seed size, fertilizing at seeding, and using a starter fertilizer containing phosphorous. In the no-till spring cropping systems study we integrated winter canola into a cropping system which has led to a full-time crop production project to evaluate seeding date, rate, and methodology for winter canola in north central Washington. Information has been disseminated to growers, scientists, administrators, agro-businesses, financial institutions, and agencies at the local, state, regional, national, and international levels. Information has been transferred via presentations, posters, journal articles, videos, extension bulletins, magazine and newspaper articles, and TV, newspaper, magazine, and radio interviews. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: This project has addressed more than 5,000 tour and field day attendees including representatives from 19 countries, administrators, policy makers, and the chief of SCS. It also has addressed several thousand scientists and agro-business personnel at local, regional, national, and international meetings. Several of these projects redirected greatly the focus of agronomic research in the PNW to long-term cropping systems. The jointed goatgrass IWM study was used as a model project for scientists in three other regions in the western United States. Growers were the main target of this project's research. For example, more than 60% of growers that attended the no-till spring cereal cropping systems field days conducted independent trials with one or more technologies, with 50% of these trials resulting in permanent adoptions. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Russian thistle is an introduced annual weed that infests millions of acres of crop and non-cropland in the western United States. Research showed that Russian thistle reduced spring wheat yield 11 to 55% and >2% for each week of interference. One Russian thistle plant uses enough water postharvest to decrease next year's wheat crop 2.5 bu/A and subsequent profit of $22.50/A. Mesorhizotron studies showed Russian thistle is so severe because root development in early spring was five to six times as rapid and extensive compared to shoot growth and that within seven days after crop harvest, Russian thistle roots begin to regenerate. Information is used to apply timely herbicide applications to reduce the impact of Russian thistle on crop yield and quality, and lower pesticide input. The use of weed-sensing technology can control Russian thistle effectively postharvest on 4.4 million acres and will reduce the use of a restricted use herbicides by 42% with an average savings of $5.37/A compared to a broadcast applicator. Diesel fuel usage was decreased 89% compared to traditional tillage. Jointed goatgrass infests more than 3 million PNW wheat acres and costs growers more than $45 million annually. Planting spring wheat was recommendation to eliminate jointed goatgrass viable seed production; however, research showed that jointed goatgrass can produce viable seeds in spring-planted wheat and that spring wheat planting needs to be delayed 2 weeks past the optimum planting time to prevent viable seed production. Delayed planting of spring wheat decreases profit 50% compared to planting winter wheat. An integrated weed management system was identified for jointed goatgrass in the Pacific Northwest. One of the best IWM systems was one-time stubble burn, spring wheat-fallow-winter wheat rotation with integrated winter wheat planting practices. This system compared to the grower's standard production practices reduced jointed goatgrass density >82% and increased winter wheat yields 23%. In addition the dockage in the IWM system was only 1.4% compared to a dockage of 19.5% in the standard system (increased growers' income $108/A). An integrated pest management system (IPM) was conducted in the annual cropping region and was the first study to demonstrate that when weeds were adequately managed, conservation production systems were more profitable than conventional systems. The conservation tillage, 3-yr rotation (winter wheat-spring barley-spring dry pea) with moderate weed management levels reduced wild oat herbicides by $14.75/A per year, and reduced predicted erosion by 90%. NRCS used this IPM information to assist growers with meeting farm bill compliance. The continuous no-till spring cropping systems study in the wheat-fallow region of the PNW was the first to examine the transitional effect of no-till spring cropping and reduced tillage wheat-fallow compared to conventional wheat-fallow. Predictive models estimated wind erosion susceptibility may be reduced up to 95% in no-till crops. The facultative spring wheat-chemical fallow system was the first example in the literature to be studied in long-term cropping systems.

Publications

• Young, D. L., T. J. Kwon, and F. L. Young. Profit and risk for integrated conservation farming systems in the Palouse. J. Soil and Water Cons. 49(6):601-606. 1994.
• Kwon, T. J., D. L. Young, F. L. Young, and C. M. Boerboom. PALWEED: WHEAT II: revision of a weed management decision model in response to field testing. Weed Sci. 46:205-213. 1998.
• Seefeldt, S., R. Zemetra, F. L. Young, and S. Jones. Production of herbicide-resistant jointed goatgrass (Aegilops cylindrica) x wheat hybrids in the field by natural hybridization. Weed Sci. 46:632-634. 1998.
• Pan, W. L., F. L. Young, and R. P. Bolton. Monitoring Russian thistle (Salsola iberica) root growth using a scanner-based, portable mesorhizotron. Weed Tech. 15:762-766. 2001.
• Yenish, J. P., and F. L. Young. Winter wheat competition against jointed goatgrass (Aegilops cylindrica) as influenced by wheat plant height, seeding rate, and seed size. Weed Sci. 52:996-1001. 2004.
• Young, F. L. Long-term weed management studies in the Pacific Northwest. Weed Sci. 52:897-903. 2004.
• Kwon, T. J., D. L. Young, F. L. Young, and C. M. Boerboom. A bioeconomic decision model for postemergence weed management in winter wheat (Triticum aestivum). Weed Sci. 43:595-603. 1995.
• Forte-Gardner, O., F. L. Young, D. A. Dillman, and M. S. Carroll. Increasing the effectiveness of technology transfer for conservation cropping systems through research and field design. Renewable Agric. and Food Systems. 19:199-209. 2004.
• Young, F. L., and M. E. Thorne. Weed-species dynamics and management in no-till and reduced-till fallow cropping systems for the semi-arid agricultural region of the Pacific Northwest, USA. Crop Protection. 23:1097-1110. 2004.
• Young, F., M. Thorne, and D. Young. Nitrogen fertility and weed management critical for continuous no-till wheat in the Pacific Northwest. Weed Tech. 20:658-669. 2006.
• Thorne, M., F. Young, and J. Yenish. Cropping systems alter weed seed banks in Pacific Northwest semi-arid wheat region. Crop Protection. 26:1121-1134. 2007.
• Bewick, L., F. Young, J. Alldredge, and D. Young. Agronomics and economies of no-till facultative wheat in the Pacific Northwest, USA. Crop Protection. 27:932-942. 2008.
• Young, F.L., L.S. Bewick, and W.L. Pan. Systems approach to crop protection research: Guidelines and challenges. In: Y.U. Berklian (ed.). Crop Rotation. Pp. 41-70. Nova Science Publishers Inc. 2008.
• Young, F., D. Ball, D. Thill, J. Alldredge, A. Ogg, Jr., S. Seefeldt. Integrated weed management systems identified for jointed goatgrass (Aegilops cylindrica) in the Pacific Northwest. Weed Tech. 24:430-439. 2010.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: ACTIVITIES: Spikelets of jointed goatgrass plants previously sprayed with imazamox herbicide in the field were collected in the fall of 2008. Spikelets were planted in greenhouse pots and grown to the 3 to 4-leaf stage in February 2009 and treated with imazamox in a dose response study to test for herbicide resistance. The study was conducted twice and no plants survived the second Greenhouse spraying. EVENTS: Symposia: Provided keynote address on Integrated Management of Jointed Goatgrass in the PNW at the National Jointed Goatgrass Review. Conferences: Presented two posters on jointed goatgrass biology, ecology, and management at the Western Society of Weed Science meeting. Workshop: Presented three talks at the Montana State Annual Grass Weed Workshop; Field Days: Organized and hosted two field days in Okanogan and Douglas Counties on feasibility of winter canola production and subsequent jointed goatgrass management. DISSEMINATION: Information presented at the review and conference to western region scientists and interested farmers: Information presented at the workshop was presented to over 200 Montana growers and extension personnel. Attendees at field days included growers, Washington State University (WSU) extension, and members of the Colville Confederated Tribes. PARTICIPANTS: Individuals: Laylah Sullivan and Eric Zakarison were Associates in Research in the Crop and Soil Sciences Department and were responsible for collecting spikelets, conducting the dose response studies in the greenhouse, and organizing the data. Partner Organizations: Washington State University, University of Idaho, National Jointed Goatgrass Research Initiative and Western Society of Weed Science. Collaborators and Contacts: Walter Neff Farms and Clark Farms. Training or Professional Development: The Associates in Research were trained in the appropriate methods of conducting dose response studies to determine herbicide resistance. TARGET AUDIENCES: Target Audiences: Mainly weed scientists, wheat breeders, and producers from the 13 western states that produce winter wheat. International audiences include the Pacific Rim and Gulf Coast Countries that require weed-free wheat for import into their countries. Efforts: Participated in national symposia and project reviews, an interstate workshop, and field days. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
CHANGE IN KNOWLEDGE: The possibility of natural selection of herbicide resistance in jointed goatgrass has never been shown before. We have shown initial resistance and this is important in the breeding, management, and production of imi-resistant wheat and subsequent weed management decisions for goatgrass. For 2 years we have shown that winter canola can be produced in north central Washington and that it can be incorporated into the winter wheat-fallow rotation for the control of jointed goatgrass. CHANGE IN ACTIONS: The number of growers in north central Washington producing canola has increased significantly as well as number of acres planted to canola. One grower modified his drill to be similar to the one we use in our research plots.

Publications

• Young, F.L. Yenish, J.P., Sullivan, L.S., Ball, D.A., Thill, D.C., and Zemetra, R.S. (2009). Pacific Northwest USDA-ARS research and extension activities (abstract), Western Society of Weed Science. Albuquerque, New Mexico. March 2009.
• Young, F.L., Yenish, J.P., Ball, D.A., and Thill, D.C. (2009). Integrated management of jointed goatgrass in the Pacific Northwest (abstract), Western Society of Weed Science. Albuquerque, New Mexico. March 2009.

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: We have been examining the natural selection of resistant jointed goatgrass in imi-resistant wheat field sprayed with imidazolinone. We have presented results at the National Jointed Goatgrass Research Initiative annual review and at other professional meetings. PARTICIPANTS: Drs. J.P. Yenish (WSU), R. Zemetra (UI), C. Mallory-Smith (OSU), provided expertise for outreach activities, genetics, and resistance, respectively. L.S. Sullivan (WSU) was project leader for greenhouse studies. TARGET AUDIENCES: This past year presentations were made at two professional meetings (Washington State Weed Conference and Montana State University Grassy Weed Workshop). Target audiences included growers, county and state extension personnel, scientists and agribusiness personnel. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Jointed goatgrass infests more than 5 million acres of winter wheat in the western United States with approximately 1 million acres in Washington. With the introduction of herbicide (imazamox) tolerant winter wheat, weed scientists are concerned that growers will select naturally for resistant populations of jointed goatgrass. The objective of this research was to determine if resistant biotypes were present at three locations in Washington where imazamox was applied to herbicide-tolerant winter wheat for the control of jointed goatgrass. Almost 20 thousand plants were produced from spikelets collected from these three locations. Twenty eight phenotypical jointed goatgrass plants survived two field-rate applications of imazamox. A subsequent dose response study was conducted on spikelets; however no plants survived. It happens there has been development of some resistant jointed goatgrass biotypes although the manifestation of resistance in these plants is not holding with the typical genetic ratios. If growers are naturally selecting for weed resistance using herbicide-tolerant winter wheat varieties, this could affect the wheat breeding programs of western universities and private companies.

Publications

• F.L. Young, L.S. Sullivan, W.L. Pan. 2008. Systems approach to crop rotation research: guidelines and challenges. In: Y.U. Berklian (Ed.), Crop Rotation. New York, Nova Science Publishers, Inc., pp. 41-70.

Progress 01/01/07 to 12/31/07

Outputs
We have been examining the natural selection of resistant jointed goatgrass in imi-resistant wheat fields sprayed with imidazolinone. We have presented results at the National Jointed Goatgrass Research Initiative annual review and at other professional meetings.

Impacts
The winter wheat/summer fallow (WW/SF) cropping system of the arid and semi-arid region of the Pacific Northwest (PNW) is characterized by winter annual grass weeds, soil borne diseases, intensive tillage, and severe wind erosion. Economically and agronomically feasible, and environmentally sustainable cropping system options need to be developed for this production region. One proposed alternative is production of no-till facultative wheat (FW). Facultative wheats, developed from WW by SW crosses, generally have less cold tolerance, a shorter period for vernalization, and start growing and flowering earlier compared to true winter wheats. Normally they can be planted either in spring or fall. In our study planting dates were early-September, early-November, and mid-March for WW, FW, and SW, respectively. The general objective of this research was to evaluate weed, disease, and insect incidence in FW rotated with chemical fallow (FW/ChF) or no-till SW (FW/SW), with both rotations being contrasted with WW/SF. Over the four years of the study, pre-harvest weed population, especially grass weeds, was highest in FW following SW compared to the other three crops. The diversity of weed species was higher for FW following SW compared to either FW following ChF or SW following FW. A pathogen that attacks the crown of wheat plants was minimal or absent on SW and FW but was present at high levels on WW. Stripe rust severely impacted SW while FW, at a later growth stage, was not impacted. Insects never reached an economic threshold during the study. The low pest incidence in FW/ChF combined with previous research on the yield and economic performance of FW, indicate this rotation may be feasible to incorporate into the semi-arid region.

Publications

• Thorne, M.E., F.L. Young, J.P. Yenish. 2007. Cropping systems alter weed seed banks in Pacific Northwest semi-arid wheat region. Crop Protection. 26:1121-1134.

Progress 01/01/06 to 12/31/06

Outputs
A field study was initiated in 2002 to determine the effect of deep plowing, no-till, herbicide-resistant wheat and absence of winter wheat on jointed goatgrass population dynamics. Yields for no-till resistant wheat following no-till spring wheat was 62 bu/A and 58 bu/A following light-tilled spring wheat. Jointed goatgrass populations were 0.9 plants/ft2 and 0.06 plants/ft2 in the no-till and tilled plots respectively.

Impacts
Jointed goatgrass infests more than 1.45 million acres of wheat land in the western United States and more than 50% of Washington's wheatland. Adoption of these technologies will increase grain quality and growers' profits in this farming region.

Publications

• Young, F.L., M.E. Thorne and D.L. Young. 2006. Nitrogen Fertility and weed management critical for continuous not-till wheat in the Pacific Northwest. Weed Technology. 20:658-669.

Progress 01/01/05 to 12/31/05

Outputs
A field study was initiated in 2002 to determine the effect of deep plowing, no-till, herbicde-resistant wheat and absence of winter wheat on jointed goatgrass population dynamics. Yields for no-till herbicide resistant wheat was 55 bu/a regardless of the previous crop rotation. Jointed goatgrass density ranged from 0.2 spikes per ft2 to 2 spikes per ft2 in winter wheat planted every 4th year and every other year respectively.

Impacts
Jointed goatgrass infests more than 1.45 million acres of wheat land in the western United States and more than 50% of Washington's wheatland. Adoption of these technologies will increase grain quality and growers' profits in this farming region.

Publications

• No publications reported this period

Progress 01/01/04 to 12/31/04

Outputs
A field study was initiated in 2002 to determine the effect of deep plowing, no-till, herbicde-resistant wheat and absence of winter wheat on jointed goatgrass population dynamics. Yields for no-till and conservation tillage spring wheat was 34 and 35 bu/a respectively. Jointed goatgrass density averaged 0.1 spike per ft2 and < 0.001spike per ft2 in no-till and conservation tilled spring wheat respectively.

Impacts
Jointed goatgrass infests more 1.45 million acres of wheat land in the western United States and more than 50 percent of Washington's Wheatland. Adoption of this technology will increase grain quality and growers' profits in this farming region.

Publications

• Yenish, J.P. and F.L. Young. 2004. Winter wheat completion against jointed goatgrass as influenced by wheat plant height, seeding rate, and seed size. Weed Science 52: 996-1001.
• Young, F.L. 2004. Long-term weed management studies in the Pacific Northwest. Weed Science. 52: 897-903.
• Young, F.L. and Mark Thorne. 2004. Weed-species dynamics and management in no-till and reduced-till fallow cropping systems for the semi-arid agricultural region of the Pacific Northwest, USA. Crop Protection. 23: 1097-1110.

Progress 01/01/03 to 12/31/03

Outputs
At the Pasco south site, both imidazolinone-resistant and conventional winter wheat were planted in the fall of 2002. Jointed goatgrass population at this site was high with an initial population of 328 spikelets yd-2. Herbicide applications were similar to the other two sites in the study with the imidazolinone-resistant winter wheat being treated with imazamox in the spring of 2003. A below average stand of wheat contributed to low yields and increased spikelet production at this site. Imidazolinone-resistant winter wheat plots averaged 750 spikelets yd-2 compared to a 593 spikelets yd-2 in conventional winter wheat plots. Average yields (clean grain) at Pasco south were nearly identical with 11.2 bu/A for the imidazolinone-resistant winter wheat, and 11.4 bu/A for the conventional winter wheat. The Pasco south site will be fallow during the 2004 growing season.

Impacts
Jointed goatgrass is the number one grass weed problem in winter wheat in WA. The prevalence of this weed forces growers into producing less profitable spring crops over multiple years in order to reduce weed competition and significantly deplete the soil seed bank. In our studies, the use of non-GMO herbicide resistant winter wheat allowed jointed goatgrass to be controlled in the growing crop and farm profitability to increase. In contrast to previous years' results, net returns (yield and dockage) were similar for both the herbicide resistant wheat and the conventional wheat. The wheat-fallow crop rotation system encompasses more than 60 percent of the winter wheat production area in WA. This system is characterized by severe wind erosion and heavy infestations of winter grass weeds. For the 2002-2003 growing season, four new cropping systems were established in the long-term, conservation-tillage spring cropping system.

Publications

• Young, F.L., J.P. Yenish, D.L. Walenta, D.A. Ball, and J.R. Alldredge. 2003. Spring-germinating jointed goatgrass produces viable spikelets in spring-seeded wheat. Weed Science. 51: 379-385.

Progress 01/01/02 to 12/31/02

Outputs
A second experiment was established in the low rainfall zone to identify stable crop production systems based on time and frequency of introducing a herbicide resistant crop for the integrated management of jointed goatgrass. Control of jointed goatgrass with imazamox in herbicide resistant wheat was good with herbicide resistant wheat plots averaging only 6 weed seeds per square yard, compared to 57 weed seeds per square yard produced in conventional, non-resistant wheat plots. Winter wheat yield was reduced 21 percent in the conventional wheat compared to the resistant wheat. Jointed goatgrass dockage was 1.03 percent in conventional wheat and 0.07 percent in resistant wheat. In satellite studies conducted at the spring no-till cropping systems site numerous new crops were evaluated for yield and other agronomic traits. Both spring mustard and spring canola planted no-till failed to produce a harvestable crop. In demonstration plots, tofu soybeans produced 8 bu per acre and the new hard white spring wheat produced 13 bu per acre.

Impacts
Jointed goatgrass is the number one grass weed problem in winter wheat in WA. The weed dictates that growers produce less profitable spring crops consecutively to deplete the weed seeds in the soil and reduce the impact of weed competition. In our studies, the use of non-GMO herbicide resistant winter wheat allowed jointed goatgrass to be controlled in the growing crop and farm profitability to increase. In our research this past year, net returns (yield and dockage) would have been greater than $24 per acre in the herbicide resistant wheat compared to the conventional wheat. The wheat-fallow crop rotation system encompasses more than 60 percent of the winter wheat production area in WA. This system is characterized by severe wind erosion and heavy infestations of winter grass weeds. If an agronomically sound and economically feasible spring cropping system can be developed for this region, crops will be diversified, wind erosion reduced, and air quality improved.

Publications

• Walenta, D.L., Yenish, J.R., Young, F.L. and Ball, D.A. 2002. Vernalization response of plants grown from spikelets of spring and fall cohorts of jointed goatgrass. Weed Sci. 50: 461-465.
• Young, F.L., Ball, D.A., Thill, D.C., Yenish, J.P. and Alldredge, J.R. 2002. Integrated management of jointed goatgrass in Pacific Northwest dryland cropping systems. Proceedings, Thirteenth Australian Weeds Conference, September 5-13, Perth, Australia, pp. 284-286.

Progress 01/01/01 to 12/31/01

Outputs
Two experiments were established in the high and low rainfall zones to identify stable crop production systems based on time and frequency on introducing a herbicide resistant crop for the integrated management of jointed goatgrass. At the high-rainfall site at Pullman, WA, control of jointed goatgrass with imazamox in herbicide resistant wheat was nearly 100%, crop safety was excellent, and dockage was 0%. In non-resistant wheat, weed population was severe and dockage averaged 0.67%. Studies were concluded with a reduced-pesticide applicator for the postharvest control of Russian thistle. Russian thistle control was similar (>90%) regardless of application method, and herbicide input was reduced 40% by the selective sprayer compared to the broadcast sprayer.

Impacts
Russian thistle infests over 3 million acres of wheat land in the PNW and is the major impediment for the adoption of alternative broadleaf crops. Growers often apply herbicides in the growing crop, preharvest (harvest aid), and postharvest to manage this weed. a new herbicide applicator was evaluated that selectively sprays only green plants compared to broadcast applicators that continually spray regardless of whether weeds are present. This technology coupled with other management strategies could reduce herbicide usage and subsequent cost to the growers by 50 percent and improve environmental quality in Washington State.

Publications

• Pan, W.P., F.L. Young, and R. Bolten. 2001. Monitoring Russian thistle root growth using a scanner-based portable mesorhizotron. Weed Technology 15: 262-766.

Progress 01/01/00 to 12/31/00

Outputs
In the fall of 2000, two experiments were initiated in the dryland wheat production area of Washington to determine the least crop rotation for effective jointed goatgrass control using imidazolenone-resistant winter wheat. The two locations include Pullman, an 18 to 22-foot rainfall zone with a wheat-fallow rotation. The main focus of the study is to identify stable crop production systems based on time and frequency on introducing a herbicide resistant crop for the integrated management of jointed goatgrass. Studies continued with the reduced-pesticide applicator for the postharvest control of Russian thistle. Weed control with paraquat plus dimron was similar for each pesticide applicator (broadcast and reduced) and control was superior to glyphosate applied with both sprayers. In a light-to-moderate weed infestation, herbicide and economic input were reduced by more than 50 percent with the reduced sprayer technology compared to the traditional broadcast technology. When the weed population was moderate-to-heavy, inputs were reduced only 13% with the reduced technology sprayer.

Impacts
Russian thistle infests over 3 million acres of wheat land in the PNW and is the major impediment for the adoption of alternative broadleaf crops. Growers often apply herbicides in the growing crop, preharvest (harvest aid), and postharvest to manage this weed. A new herbicide applicator is being evaluated that selectively sprays only green plants compared to broadcast applicators that continually spray regardless of if weeds are present. If successful, this technology could reduce herbicide usage and subsequent cost to the growers by 50 percent.

Publications

• No publications reported this period

Progress 01/01/99 to 12/31/99

Outputs
An action threshold decision aid to assist growers in managing jointed goatgrass has been developed. This predictive model will help growers decide when to rotate to a spring crop instead of growing winter wheat. The model is based on the first year jointed goatgrass densities in winter wheat and the subsequent winter wheat yield loss the second year. An example of this relationship is that 1-5 plants/m2 of jointed goatgrass in the first year of winter wheat reduced winter wheat yield loss the second year 3-30%. New equipment has been purchased to continue to conduct studies on reducing pesticides to control Russian thistle postharvest. The pesticide application has been built.

Impacts
(N/A)

Publications

• Young. F.L., S.S. Seefeldt, and G.F. Barnes. 1999. Planting geometry of winter wheat can reduce jointed goatgrass spikelet production. Weed. Tech. 13:183-190.
• Ball, D.A., F.L. Young, and A.G. Ogg, Jr. 1999. Selective control of jointed goatgrass with imazamox in herbicide-resistant what. Weed. Tech. 13:77-82.
• Schillinger, W.F., R.I. Papendick, R.J. Veseth, and F.L. Young. 1999. Russian Thistle skeletons provide residue in wheat-fallow cropping systems. J. Soil Water Cons. 54:506-509.

Progress 01/01/98 to 12/31/98

Outputs
Russian thistle continues to be the major weed in no-till spring cereals grown in the arid and semiarid region of the PNW while growers are transitioning from winter wheat-fallow to spring crops. Herbicide resistance is a problem and herbicides with different modes of action are rotated annually to prevent/delay resistance in Russian thistle. The weed-seeker herbicide applicator, which showed promising results for controlling Russian thistle post-harvest while reducing pesticide input and subsequent costs, was not used on the cropping system study this year. The original developing company sold this technology to another company, which recalled all of the equipment. The use of herbicide-resistant wheat to control jointed goatgrass appears promising in the PNW. Imazamox, applied at 0.024 lb. ai/A, controlled jointed goatgrass 90 percent and reduced dockage from 26 percent, in the weedy check, to less than 1 percent. However, one draw back that growers need to be aware of in this system is that in only two years jointed goatgrass crossed with the herbicide-resistant wheat to produce herbicide-resistant hybrids. Six of the seven hybrids produced survived Imazamox at 0.064 lb. ai/A, a 2x herbicide rate. Specific strategies will have to be used to manage the resistant problem from occurring in farmers' fields.

Impacts
(N/A)

Publications

• No publications reported this period

Progress 01/01/97 to 12/31/97

Outputs
Russian Thistle plants were allowed to grow without intraspecific competition in early August until killing frost in October. Soil water was measured with neutron attenuation techniques from 0.3 m to 3.0 m from the base of the plant and to a depth of 1.8 m. Individual Russian Thistle plants extracted an average of 51 liters of soil water. A portable rhizotron and scanning system to provide the capability to study the growth and development of Russian Thistle root systems has been developed. Use of the rhizotron allows the examination of spatial and temporal in situ root development without the use of destructive sampling and manual measurements. Isoxaflutole pulse metribuzin-enhanced broadleaf weed control compared to either herbicide alone. Broadleaf weed control was reduced slightly when MON37532 was added to isoxaflutole and weed control was reduced completely when diclofop-methyl was tank-mixed with isoxaflutole.

Impacts
(N/A)

Publications

• LEE, G.A. AND A.G. OGG, JR. 1996. Kochia control in spring wheat with postemergence herbicide treatments. Proc. Western Soc. Weed Sci. 49:85-86.
• OGG, A. G., JR. 1996. Integrated management of JGG in dryland cropping systems inthe PNW. Proc. PNW JGG conference. Pasco, WA. pp. 25-28.
• OGG, A. G., JR. 1996. Weed management for conservation tillage systems. Proc. Ann. Conference Washington State Weed Assn. pp 33-35.
• OGG, A. G., JR. 1996. Weed science research & extension in Washington--past, present, and future. Proc. Ann. Conf. Washington State Weed Assn. pp 107-110.
• SEEFELDT, S., AND A.G. OGG, JR. 1996. Competitive winter wheat cultivars. Proc. PNW JGG conference. Pasco, WA. pp 21-24.
• SEEFELDT, S.S., E.P. FUERST, G.P. IRZYK, D.R. GEALY, A. SHUKLA, D. HOFFMAN, AND B.D. BREWSTER. 1996. Diclofop-resistant Avena fatua from the Willamette Valley of Oregon. Proc. Second International Weed Congress II:511-516.

Progress 01/01/96 to 12/30/96

Outputs
Sulfosulfuron (S.) (MON-37532) applied postemergence to dormant winter wheat at 0.026 or 0.035 kg/ha controlled downy brome selectively. S. applied to nondormant wheat when night temperatures were freezing injured the crop. S. plus triallate applied & incorporated shallowly before planting winter wheat suppressed JGG populations, but did not reduce weed biomass or increase wheat grain yields. Metribuzin applied postemergence in early March with 0.13% nonionic surfactant injured winter wheat signif. when night temps were freezing, but controlled downy brome better than metribuzin applied with 50% liquid urea. Crop injury from carfentrazone (F-8426) applied postemergence to spring barley was reduced when MCPA was added to the spray solution. Control of wild oat with tralkoxydim was improved by adding 1.7 kg/A ammonium sulfate to spray solutions. 2,4-D was antagonistic to control wild oat with tralkoxydim, whereas MCPA was not. Time of viable seed production by JGG could be predicted by calculating growing-degree-days after Jan. 1. Inheritance of diclofop resistance in wild oat was conferred by a single, partially dominant nuclear gene with multiple alleles. In a dry env., JGG reduced yield of Stephens winter wheat 33% whereas in a moist env. JGG reduced grain yield only 17%. In a dry env., the tallest wheat varieties were not always most competitive with JGG.

Impacts
(N/A)

Publications

• OGG, A. G., JR. 1996. Integrated management of JGG in dryland cropping systems inthe PNW. Proc. PNW JGG conference. Pasco, WA. pp. 25-28.
• OGG, A. G., JR. 1996. Weed management for conservation tillage systems. Proc. Ann. Conference Washington State Weed Assn. pp 33-35.
• OGG, A. G., JR. 1996. Weed science research & extension in Washington--past, present, and future. Proc. Ann. Conf. Washington State Weed Assn. pp 107-110.
• SEEFELDT, S., AND A.G. OGG, JR. 1996. Competitive winter wheat cultivars. Proc. PNW JGG conference. Pasco, WA. pp 21-24.
• LEE, G.A. AND A.G. OGG, JR. 1996. Kochia control in spring wheat with postemergence herbicide treatments. Proc. Western Soc. Weed Sci. 49:85-86.
• SEEFELDT, S.S., E.P. FUERST, G.P. IRZYK, D.R. GEALY, A. SHUKLA, D. HOFFMAN, AND B.D. BREWSTER. 1996. Diclofop-resistant Avena fatua from the Willamette Valley of Oregon. Proc. Second International Weed Congress II:511-516.

Progress 01/01/95 to 12/30/95

Outputs
The mechanism of diclofop resistance in wild oat was an alteration in acetyl CoAcarboxylase, the site of action. Diclofop resistance is controlled primarily by a single, partially dominant gene. Differences in levels of resistance to diclofop among wild oat biotypes and cross-resistance to related herbicides indicate tha there ismore than one type of resistant enzyme allele. Tank mixing bromoxynil, bromoxynil plus MCPA, 2,4-D estern, or MCPA ester with tralkoxydim did not reduce the control of wild oat in spring wheat. However, tank mixes of tralkoxydim and bromoxynil were antagonistic to the control of lambsquarters and delayed slightly the growth and ripening of 'Baronesse' spring barley. Russian thistle control in spring, no-till barley with 2,4-D ester or 2,4-D ester plus bromoxynil was similar when applied with a conventional hydraulic sprayer and a low-pressure, low-volume, air-assisted sprayer. However, control with bromoxynil applied alone was low with the air-assist sprayer compared to the conventional sprayer. Dicamba at 0.11 kg/ha and dicamba plus 2,4-D at 0.11 + 0.28 kg/ha controlled sulfonylurea-resistant kochia in spring wheat. Dicamba caused temporary prostrate growth of the wheat, but did not reduce grain yield. An experimental herbicide, F8426 (carfentrazone, controlled kochia in spring wheat and spring barley. The above information will be useful to extension personnel, fieldmen and farmers when plans are developed for weed control in small-grains.

Impacts
(N/A)

Publications

Progress 01/01/94 to 12/30/94

Outputs
Dimethenamid applied preplant incorporated or preemergence at 1.1 or 202 kg/ha controlled downy brome in winter wheat, but reduced wheat stands and reduced grain yields. Dimethenamid injured winter wheat the most when it was applied preplant incorporated and when wheat was planted less than 2.0 cm deep. Fluxofenim, a seed safener, provided some but still inadequate, protection against dimethenamid injury to wheat. An experimental herbicide, F8426, plus 2,4-D applied postemergence at 0.035 + 0.28 kg/ha controlled Russian thistle selectively in spring barley and henbit, shepherds purse, bedstraw, tumble mustard, and coast fiddleneck selectively in winter wheat. Biotypes of diclofop resistant wild oat have different level of resistance to diclofop, and have differing levels of cross-resistance to other aryloxyphenoxy and cyclohexanidione herbicides. Resistance to diclofop was not due to differences in uptake, translocation, or metabolism of the herbicide. Acetyl CoA carboxylase enzyme in resistant wild oat biotypes B and C were 3 times less sensitive than a susceptible biotype to diclofop acid. In both whole-plant and enzyme studies, the C biotype was also resistant to fenoxaprop whereas the B biotype was sensitive to fenoxaprop. In the B biotype, resistance is due to a single gene with incomplete dominance. PALWEED:PEA, a bioeconomic model for optimal herbicide rates in dryland pea, predicted maximum profits using only two types of herbicide applications; preplant incorporated and postemergence f.

Impacts
(N/A)

Publications

Progress 01/01/93 to 12/30/93

Outputs
Winter wheat planted with a deep-furrow drill was not injured by preplant, shallowly incorporated metolachlor, triallate, and trifluralin applied at recommended or twice recommended rates. When planted with a double-disc drill, wheat was injured visibly and stand and yield were reduced by preplant trifluralin. Oxabetrinil, applied to seed, did not protect wheat from injury by trifluralin. Only metolachlor at 2.2 to 4.5 kg/ha reduced jointed goatgrass populations. UCC-C4243 applied preemergence at 0.07 to 0.14 kg/ha controlled broadleaf weeds 100% and suppressed downy brome 70% in winter wheat. When UCC-C4243 was incorporated, control of broadleaf weeds was reduced, whereas control of downy brome remained similarly to preemergence applications. Preplant surface and postplant incorporated applications of UCC-C4243 were least effective. UCC-C4243 wettable powder applied postemergence at 0.07 and 0.14 kg/ha did not injure wheat, controlled broadleaf weeds 93 to 97%, reduced downy brome populations 63 to 80%, and increased winter wheat yield 11 to 15%. The half-life of UCC-C4243 on a dry soil as found to be 18 days. Photodegration by UV light was found to be the major mode of activity loss of UCC-C4243. As little as 0.5 cm of overhead moisture moved the herbicide into the soil and prevented UV degradation. Light was found to be necessary for herbicidal activity of UCC-C4243. UCC-C4243 inhibited the porphyrin biosynthetic pathway.

Impacts
(N/A)

Publications

Progress 01/01/92 to 12/30/92

Outputs
When herbicide use was reduced by 50% in the first year of a 3-year IPM study, yield of no-till winter wheat was reduced by 5%, however, no-till winter wheat still yielded 28% more than conventionally tilled winter wheat. Yield of conventionally tilled winter wheat did not decrease when herbicide use was reduced by 50%. These first year results suggest that the amount of herbicides used can be reduced in conventionally tilled but not in no-till winter wheat. Populations of corn gromwell, lambsquarters, Galium sp., and tumble mustard were reduced by 90% or more in winter wheat with UCC-C4243 applied preemergence at 0.03 kg/ha, whereas 0.10 kg/ha was required to reduce populations of henbit, mayweed chamomile, and wild buckwheat by 90%. The preemergence activity of UCC- C4243 was reduced significantly when rain did not fall for 14 days after application. UCC-C4243 appears to be a safe and effective new herbicide for controlling broadleaf weeds in wheat, but rain must fall soon after application or weeds will not be controlled. Resistance to diclofop, a herbicide used to control wild oats in wheat and barley, has been verified in wild oat biotypes from Oregon. Recently, resistant biotypes have been reported in Idaho and Washington and cross-resistance to other graminicides has been verified. Resistance mechanism may be at the acetyl-Co A carboxylase step in fatty acid synthesis. Diclofop resistance in wild oats has the potential to be a major problem for production of wheat and barley.

Impacts
(N/A)

Publications

Progress 01/01/91 to 12/30/91

Outputs
IN A SIMULATED DRIFT STUDY, 0.1X RATES OF THIFENSULFURON+TRIBENURON REDUCED CHLOROPHYLL CONTENT OF LEAVES BY 41% & THE YIELD OF PEAS & LENTILS 23 & 12% RESPECTIVELY, WHEREAS THE 0.01X DID NOT REDUCE YIELDS. QUANTIFIES THE EFFECTS OF HERBICIDE DRIFT & HELPS ACTION AGENCIES IN PREPARING REGULATIONS. SEMI-PURIFIED PERCIPITATES & CELL-FREE BROTH FROM PSEUDOMONAS FLUORESCENS STRAIN D7 REDUCED LIPID BIOSYNTHESIS IN DOWMY BROME ROOTS. RESPIRATION, MITOTIC INDICES, & BIOSYNTHESIS OF PROTEIN, RNA, & DNA WERE NOT AFFECTED APPRECIABLY. CONTRIBUTES TO THE BASIC UNDERSTANDING OF THE MODE OF ACTION OF BACTERIAL TOXINS THAT SUPPRESS DOWNY BROME. D7 APPLIED AT 100,000,000 CFU PER SQUARE METER TO FIELD PLOTS IN EASTERN WASHINGTON DID NOT SURVIVE IN SUFFICIENT NUMBERS TO REDUCE DOWNY BROME POPULATIONS OR BIOMASS IN WINTER WHEAT. SURVIVAL OF THE BACTERIA IN THE FIELD IS A MAJOR CONSTRAINT BLOCKING THE DEVELOPMENT OF THIS BIOCONTROL TECHNOLOGY. UBI-C4243, AN EXPERIMENTAL HERBICIDE APPLIED PREPLANT INCORPORATED, PREPLANT SURFACE, POSTPLANT INCORPORATED, OR PREEMERGENCE AT 0.07 KG AI/HA CONTROLLED BLUE MUSTARD & COAST FIDDLENECK SELECTIVELY IN WINTER WHEAT. WHERE APPLIED AT 0.14 KG AI/HA, UBI-C4243 ALSO CONTROLLED DOWNY BROME. THIS NEW HERBICIDE PROVIDES A POTENTIAL NEW TOOL FOR CONTROLLING MANY WEEDS IN WHEAT. PARAQUAT & GLYPHOSATE APPLIED TWO WEEKS BEFORE WHEAT HARVEST CONTROLLED RUSSIAN THISTLE 87 & 85%, RESPECTIVELY.

Impacts
(N/A)

Publications

Progress 01/01/90 to 12/30/90

Outputs
Pseudomonas fluorescens strain D-7 rif applied to the soil surface in the fall of 1989 in various field experiments did not survive in the soil. However, the bactria did survive and colonize winter wheat roots. By July, 1990 the bacteria were detected in only one of 10 test locations. In 1989-90, the bacteria did not reduce the populations or growth of downy brome in any of the field experiments. In hydroponic solution, D7 cell-free extract was 40% less inhibitory to wheat than to downy brome plants. Sulfosate and glyphosate applied at 0.2 kg ai/ha plus 0.5% nonionic surfactant controlled weeds in fallow similarly. An experimental herbicide, UBI-C4243 at 0.07 to 0.21 kg ai/ha applied preemergence to winter wheat controlled nine different broadleaf weeds selectively in wheat. Paraquat at 0.56 kg ai/ha and glyphosate at 0.84 kg ai/ha controlled Russion thistle greater than 85% after preharvest or postharvest treatments. Preharvest treatments decreased weed fresh weight and thus increased harvest efficiency and improved grain quality. In wheat, downy brome, and jointed goatgrass protoplasts, low temperatures reduced inhibition of net photosythesis by metribuzin and ethylmetribuzin possibly by reducing inhibition of electron transport and/or O2 production in thylakoids, but not by reducing thylakoid binding or protoplast uptake.

Impacts
(N/A)

Publications

Progress 01/01/89 to 12/30/89

Outputs
In a survey of 5000 naturally occurring soil bacterial isolates, 6% inhibited downy brome and not wheat and 4% inhibited jointed goatgrass but now wheat. Downy brome inhibitory bacteria survived well in solutions containing commonly used herbicides. In field studies at Lind, WA, downy brome populations were reduced about 30% when bacteria were applied before plant emergence. Diclofop, triallate, triallate plus trifluralin, atrazine, ethylmetribuzin, and chlorsulfuron plus metsulfuron applied preplant or preemergence to winter wheat reduced downy brome populations 26 to 93%. Bacteria applied soon after wheat planting reduced downy brome populations by an average of 13% beyond the reduction given by the herbicides. Three isolates of bacteria that retarded jointed goatgrass in the laboratory did not reduce jointed goatgrass populations or biomass in the field. A toxin produced by the bacteria has been tentatively identified as a short chain, highly water soluble polypeptide associated with a pigment. In the presence of the toxin, cell membranes degrade. In the laboratory, cool temperatures reduced the uptake of and the inhibition of photosynthesis by metribuzin and ethylmetribuzin in wheat, downy brome, and jointed goatgrass. The selectivity between wheat and jointed goatgrass was about three times greater for ethylmetribuzin than for metribuzin.

Impacts
(N/A)

Publications

Progress 01/01/88 to 12/30/88

Outputs
In the greenhouse at 18C, 'Stephens' winter wheat had a greater shoot-to-root ratio and twice as much leaf area per plant as did jointed goatgrass. Jointed goatgrass did not produce a coleoptilar tiller and had only half the number of roots at the coleoptile node as did winter wheat. This information may be useful in explaining differential herbicide uptake from soil and in predictive modelling of plant growth. Galiu sp. (bedstraw) was found in 49 of 72 wheat fields surveyed in the eastern Palouse region. Weed densitieswere highest at the edges of fields. Of the many characteristics examined to date, all but optimum germination temperature indicates that the Galium sp. in the eastern Palouse is Galium spurium and not Galium aparine. The two species respond differently to some herbicides, which would be important to those making herbicide recommendations. In the laboratory, the growth rates of jointed goatgrass and wheat in hydroponics were 5 to 10 times more sensitive to metribuzin than to ethyl metribuzin. Growth rates matched photosynthetic rates closely. Plants grown at 30C were several times more sensitive to the herbicides than were plants grown at 10C. These results may help explain variability in weed control observed in the field.

Impacts
(N/A)

Publications

Progress 01/01/87 to 12/30/87

Outputs
In the greenhouse, the growth of roots and shoots of jointed goatgrass and winter wheat followed closely a precise timing of root development to shoot development in correlation with growing degree days. By the 8-leaf stage, winter wheat had a greater shoot to root dry weight ratio and twice the leaf area as jointed goatgrass; however, the total root length and tiller number for both species were similar. As the temperature of isolated protoplasts was decreased from 25 to 10C, the concentration of ethyl metribuzin required to inhibit net photosynthesis by 50% (PI (50)) increased by by 350% for jointed goatgrass and by 430% for downy brome. Based on PI(50) values, metribuzin was 8 to 9 times more inhibitory at 10C and 4 to 5 times more inhibitory at 25C than was ethyl metribuzin. These results show that cool temperatures reduced the activity of ethyl metribuzin more than the activity of metribuzin. Ethyl metribuzin (SMY-1500) applied postemergence in the fall at 1.7 kg/ha controlled downy brome an average of 80% and increased winter wheat yields 14%. When 0.14 kg/ha of metribuzin was tank-mixed with 1.7 kg/ha of ethyl metribuzin, downy brome was controlled 97%. In fields where downy brome was dense, treatments increased wheat yields 35 to 45%. Ethyl metribuzin applied postemergence in the fall alone at 1.7 kg/ha or in combination with 0.14 kg/ha of metribuzin suppressed jointed goatgrass about 50%; however, wheat yields were increased only about 10%.

Impacts
(N/A)

Publications

Progress 01/01/86 to 12/30/86

Outputs
Ethyl metribuzin applied postemergence in the fall in no-till winter wheat at 1.1 kg/ha controlled downy brome 90%. Jointed goatgrass was more tolerant of ethyl metribuzin and was controlled only 73% by 1.7 kg/ha. Spring applications of ethyl metribuzin were less effective, especially against jointed goatgrass. After one year of preventing seed production, the number of viable seeds of jointed goatgrass in the soil decreased 78% in conventionally plowed plots, but only 37% in no-till plots. During the first year of the study, seedlings of jointed goatgrass were six times as numerout in no-till plots as in plowed plots. In the greenhouse replacement studies, winter wheat and jointed goatgrass were similar in competitive ability, but both were more competitive than downy brome. In field and greenhouse studies, metribuzin and ethyl metribuzin reduced photosynthesis of jointed goatgrass to zero within 24 hours. Drought stress immediately before and after postemergence application of metribuzin did not reduce control of jointed goatgrass. Under field conditions, metribuzin was lost completely from downy brome and wheat leaves in 14 days. Germination of mayweed chamomile seed in soil was optimal at constant 30C. Total germination of mayweed was stimulated by soil moisture levels above field capacity, whereas germination was inhibited when the water potential fell below the permanent wilting point. Mayweed germination was similar at soil pH's of 4.7, 5.2, or 6.

Impacts
(N/A)

Publications

Progress 01/01/85 to 12/30/85

Outputs
Metribuzin selectivity between downy brome and winter wheat can be accounted forby higher root uptake, lower metabolism, and small plant size of downy brome. Exposing downy brome seedlings to 8 hr days at 3 C for 30 days induced rapid flowering whereas long days or warm temperatures or vernalizing the seed did not induce rapid flowering. Fluazifop-butyl applied postemergence at 0.07 or 0.28 kg/ha prevented seed production in downy brome more effectively than did similar rates of DPX-Y6202. Moderate water deficit (-5 bar) during culm elongation or just prior to anthesis reduced photosynthesis rate, increased stomatal resistance, and reduced the number and size of downy brome seed. Ethyl metribuzin applied preemergence or early postemergence in the fall alone or in combination with low rates of metribuzin controlled downy brome and jointed goatgrass selectively in winter wheat. In 1985, spring applications were ineffective. A 5-yr integrated pest management study was initiated to investigate the interactions of crop rotations, tillage practices, and weed management levels on the yield and quality of small grains and legumes. Wild oats at 35 to 65 plant/m reduced lentil yields if allowed to interfere with the crop for more than 5 weeks. When applied to wild oats in the 2- to 3-leaf stage, DPX-Y6202 at 0.14 kg/ha controlled the wild oats and prevented crop yield reductions. Mayweed chamomile populations were higher in reduced than in conventionally tilled plots.

Impacts
(N/A)

Publications