UCANR

Agronomy & Weed Management

Agronomy Program Overview

Agronomy is the branch of agricultural science focused on field crop production and soil management, integrating biology, chemistry, ecology, soil science, and plant science to improve how crops are grown and how soils are cared for. Agronomy blends science, technology, and practical field management to ensure crops grow efficiently while preserving natural resources. Agronomy in the low desert is shaped by extreme heat, intense sunlight, saline soil, and limited, highly managed irrigation water. In this environment, agronomy becomes the science of optimizing crop production under environmental stress with focus on adapting crop and soil management to harsh arid conditions.

The Agronomy and Weed Management Program serves growers, Pest Control Advisors (PCAs), industry and agricultural partners, and community stakeholders across the low desert region of Southern California. The program provides research-based solutions to improve crop productivity, enhance soil and water stewardship, manage invasive and herbicide‑resistant weeds, and support the long-term sustainability of desert agriculture. Through applied research, field demonstrations, and extension outreach, the program addresses the unique challenges of farming in arid environments characterized by extreme heat, salinity, and limited water resources.

Agronomy Program Objectives

  • Improve crop productivity and quality through research on best resource management practices, variety selection, alternative crops, and nutrient optimization.
  • Advance integrated weed management strategies that reduce reliance on herbicides and address emerging weed threats.
  • Support crop diversification by evaluating alternative and specialty crops suited to desert conditions.
  • Promote climate‑smart agriculture through soil health practices, water-use efficiency, and adaptive crop management.
  • Strengthen collaboration with universities, commodity boards, agencies, and local partners to address regional agricultural priorities.
  • Provide timely extension outreach via field days, workshops, publications, and direct support to growers and PCAs.

EXTERNAL IMAGE

The Low Desert Agronomy Advisor – Oli Bachie

Dr. Oli G. Bachie is the UC Cooperative Extension Agronomy and Weed Management Advisor serving Imperial, Riverside, and San Diego counties. He has also served as County Director for Imperial and San Diego counties. Bachie’s work focuses on crop production systems, weed ecology and management, and the introduction of alternative crops for arid environments. Dr. Bachie’s background spans Ethiopia, the Philippines, Canada, and the United States, giving him a global perspective on sustainable agriculture and desert cropping systems. With his current assignment Bachie covers Imperial, Riverside, and San Diego Counties. Bachie temporarily overlooks weed management until a new weed management is hired (undergoing recruitment).

Focus Areas of Agronomy in the Low Desert

  • Forage Crop Production Alfalfa, sudangrass, Bermudagrass, Kleingrass, and Rhodes grass management, including irrigation, fertility, and harvest optimization.
  • Field Crops Wheat, cotton, sugar beets, and small grains, with emphasis on yield improvement, pest management, and salinity tolerance.
  • Alternative & Industrial Crops Guayule (natural rubber), bioenergy crops, sorghum, teff, moringa, Quinoa, and other emerging commodities suited to desert climates.
  • Weed Management Integrated strategies for invasive weeds, herbicide resistance, and weed–crop competition in forage and field crops.
  • Soil & Water Management, soil health improvement, and efficient irrigation and fertilization practices under extreme desert conditions.
  • Pest Management Integration Collaboration with entomology and nematology programs to address cross‑disciplinary pest pressures.

Current Projects Led by Dr. Bachie

  • Alfalfa Variety and Irrigation Trials evaluating yield, quality, and water-use efficiency.
  • Weed Management Trials targeting invasive and herbicide‑resistant species in forage, field crops, and horticultural and vegetables.
  • Guayule Research for Natural Rubber Production, including weed management for crop establishment.
  • Sugar Beet (not to be produced anymore following the untimely closure of Spreckels sugar processing industry in Brawley) and Cotton Production Studies focusing on fertility, pest management, and other crop production issues.
  • Alternative Crop Evaluations identifying new crops with economic potential for the low desert.
  • Soil Health and Climate‑Smart Practices including cover cropping, and organic amendments.
  • Interdisciplinary Pest Management Projects integrating weed, insect, and nematode control strategies.

Major Publications 

Peer‑reviewed journal articles on weed management, forage crop production, and desert agronomy systems. Contributions to Alfalfa & Forage News, county-based crop updates. • Conference proceedings presented at the American Society of Agronomy, Western Society of Weed Science, and California Alfalfa & Forage Symposium. • Technical reports and grower guides, including project trial reports, pest management updates, and crop production guidelines for Imperial Valley growers.

  1. Bachie O. and A. Babu (2025). Cotton being revisited in the Imperial Valley? Imperial AgBrief 28 (5) 113-117.
  2. Bachie O., P. Waisen, and N. Kniffin (2025). The 2025 Vegetable Crops Guidelines. University of California Cooperative Extension Circular 104-V (Access). 85 Pages
  3. Bachie O., Montazar A., and N. Kniffin (2025). The 2025 Field Crop guidelines. University of California Cooperative Extension Circular 104-V (Access). 50 PP
  4. Bachie O and A. Montazar (2025). Results from a research trial on the erodibility of soil applied fertilizers in the low desert. Imperial AgBrief 28 (4) 78-83
  5. Bachie O. and J. Nguyen (2025). UCANR Vice president Glenda Humiston visits the Imperial County. Imperial AgBrief 28(6) 133-134.
  6. Bachie O. (2025). Broomrape; a potentially devastating parasitic weed of various crops. Imperial AgBrief. 28 (2) 26-28
  7. Philp W., Bachie O., et al., (2025). Environmental DNA analysis revealed cover cropping in low desert increased microbial activity leading to improved nutrient cycling and Okra yield. Imperial AgBrief 28 (3) 54-60.
  8. Waisen, P., Nguyen, H.C, Lofton, E., Bachie, O., Montazar, A., and Resendiz, A. 2025. Environmental DNA analysis revealed cover cropping in the low desert increased microbial activity and improved nutrient cycling and okra crop yield. Imperial Agricultural Briefs 28(3):62-68. (Access)
  9. Waisen, P., Bachie, O., Montazar, A., Nguyen, H. C., Lofton, E., Resendiz, A. 2025. Metabarcoding soil environmental DNA revealed cover cropping in low desert increased microbial activity and improved nutrient cycling and crop yield. Abstract. American Phyto pathological Society Plant Health Annual Meeting. Honolulu, HI, August 1-5 (Access).
  10. Bachie O, Latack B, and A. Montazar (2024). Sudan grass quality can be affected by fertilizer and irrigation water levels. Imperial AgBrief. 27:(5) 60-63.
  11. Bachie O. and W. Burayu (2024). Utilizing local and global knowledge for sustainable agricultural production: Lesson from Oromia and the American low desert. 29 (1) 18-28.
  12. Bachie O, Montazar A, and B. Latack (2024).  Application of High N fertilizer and irrigation may not necessarily yield high biomass of Suda grass.  Imperial AgBrief 27 (6) 44-47
  13. Bachie O. (2024). May Guayule be a future crop of the Imperial Valley? Imperial AgBrief 27 (6) 88-90.
  14. Bachie O., Montazar A, and B. Latack (2024). Nitrogen Fertilizer and Irrigation Best Management Practices for the Low Desert Sudan Grass Production Systems. In the 32ND ANNUAL FREP/WPH NUTRIENT MANAGEMENT CONFERENCE proceedings | Summaries of Current FREP Projects. Pages 66-70.
  15. Waisen, P., Nguyen, H.C, Mosase, E., Bachie, O., Montazar, A., and Resendiz, A. 2024. Pre-Plant Benefits of Summer Cover Crops in Low Desert Vegetable Production. Imperial Agricultural Briefs 27(8):98-105. (Access Archived)
  16. Bachie. O and W. Burayu. 2024. Utilizing Local and Global Knowledge for Sustainable Agricultural Production: Lessons from Oromiya and the American Low Desert. The Journal of Oromo Studies ISSN:1070-2202: 29 (1) 77-99.
  17. Bachie O. (2023). The Importance of identifying agricultural weeds. Imperial AgBrief 27 (7) 105-108.
  18. Bachie O. and A. Montazar (2022). The 33rd Annual Fall Desert Crops Workshop report. Imperial AgBrief 25 (11) 151-154
  19. Bachie O. (2022). The Corn leaf aphid (Riopalosiphum maidis) in the low desert. Imperial AgBrief 25 (11) 159-162.
  20. Bachie O. (2022). UCCE Imperial County gave a talk and had an exhibit at the "Pesky Pests" event. Imperial AgBrief (25 (8) 129-130.
  21. Dugassa B., Diba F., and O. Bachie (2021). Climate Change and Public Health in the Oromia Regional State in Ethiopia and Its Implications for the Nile Basin. American Journal of Public Health Research. 9 (6) 257-269.
  22. Barman, Apurba; Bachie, Oli (2021). Effective and Safe Desiccants for Alfalfa Seed Production. 24:10, 183-185. November 2021.         
  23. Burman, Apurba; Bachie, Oli (2021). Viral Disease on Lettuce. The Imperial County Agricultural Briefs. 24:3, 31-35. March 2021
  24. Devkota, Pratap; Bachie, Oli (2021). Evaluation of the summer slump application of saflufenacil on nondormant conventional alfalfa. Crop, Forage & Turfgrass Management. https://doi.org/10.1002/cft2.20095. 7, 8. March.
  25. Bachie O. 2023. The Importance of Identifying Agricultural Weeds.  Ag Brief. July 2023. 26 (7) 105-108. http://ceimperial.ucanr.edu/newsletters/Ag_Briefs33282.pdf.
  26. Bachie O. 2022. A talk and exhibit at the Pesky Pests event.  Ag Brief. September 2022. 25 (8) 129-130. http://ceimperial.ucanr.edu/newsletters/Ag_Briefs94681.pdf.
  27. Devkota P., O. Bachie. 2021. Evaluation of the summer slump application of saflufenacil on nondormant conventional alfalfa. Crop forage & Turfgrass management. https://doi.org/10.1002/cft2.20095
  28. Montazar A., Bachie O., Corwin D., and D. Putnam. 2020. Feasibility of Moderate Deficit Irrigation as a Water Conservation Tool in California’s Low Desert Alfalfa. Agronomy. 10 (11): 1-21. https://www.mdpi.com/2073-4395/10/11/1640
  29. Bachie O. 2020. UC cooperative extension update in the context of covid-19. Imperial County Ag Brief. May 2019. 23 (5):74-75. http://ceimperial.ucanr.edu/newsletters/Ag_Briefs84883.pdf   
  30. Bachie O. and B. Latack. 2020. Biomass productivity and forage quality comparison of new and existing forage crops for the low desert environment. Imperial County Ag Brief. Apr 2020. 23 (8):134-139, http://ceimperial.ucanr.edu/newsletters/Ag_Briefs86488.pdf .
  31. Bachie O., Salgado K., and R. Magos. 2020. The 2020 CDFA Healthy Soil Incentive Program and Imperial Count awardees. Imperial County Ag Brief. Jun 2020. 22 (6):89-90, http://ceimperial.ucanr.edu/newsletters/Ag_Briefs85332.pdf
  32. Bachie O., Salgado K., and R. Magos. 2020. The 2020 CDFA Healthy Soil Incentive Program and Imperial Count awardees. Imperial County Ag Brief. Jun 2020. 22 (6):89-90, http://ceimperial.ucanr.edu/newsletters/Ag_Briefs85332.pdf
  33. Bachie. O., Santiago L., and M. McGiffen 2019.  Physiological Responses of Onion Varieties to varying Photoperiod and Temperature Regimes. Agriculture. 9: 2-8. doi:10.3390/agriculture9100214
  34. Bachie. O and M. Rethwisch. 2019.  Sugarbeet alternative insect pest management pesticides are being tested at DREC. Ag Brief. Feb 2019. 22 (2):23.23. http://ceimperial.ucanr.edu/newsletters/Ag_Briefs85332.pdf
  35. Bachie. O and W. Burayu. 2019. Utilizing Local and Global Knowledge for Sustainable Agricultural Production: Lessons from Oromiya and the American Low Desert. In 33rd Annual Conference Proceedings. page 304-318. The Oromo Studies Association.  Jul 26-28, 2019. Rift Valley University, Finfinnee, Oromia. https://www.oromostudies.org/wp-content/uploads/2019/07/2019-OSA-Abstracts.pdf
  36. Bachie O. and J. Liu. 2019. Quinoa; A pseudo-cereal crop for the low desert. Imperial County Ag Brief. Apr 2019. 22 (4):63-66.
  37. Bachie O. and J. Liu. 2019. Potential herbicide resistant Mexican sprangle top in the Imperial Valley. Imperial County Ag Brief. Dec 2019. 22 (11):200-201,

Refer to this link:  https://ucanr.edu/search/all?keys=Oli+Bachie

Source URL: https://ucanr.edu/county/cooperative-extension-imperial-county/agronomy-weed-management