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Hazelnut growth and weed control in response to selected preemergence herbicides

Published online by Cambridge University Press:  22 August 2022

Rafael M. Pedroso
Former Research Associate, Oregon State University, Department of Horticulture, Corvallis, OR, USA Assistant Professor, University of São Paulo, Crop Science Department, Piracicaba, SP, Brazil
Marcelo L. Moretti*
Assistant Professor, Oregon State University, Department of Horticulture, Corvallis, OR, USA
Author for correspondence: Marcelo L. Moretti, Assistant Professor, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331. Email:


Hazelnut hectarage is expanding in Oregon. Weed competition in young orchards can severely reduce the growth and survival of plants. New orchards replace crops, including grass seed fields, which often are infested with herbicide-resistant weeds, including Italian ryegrass. This research evaluated hazelnut tolerance to pronamide, pyroxasulfone, and S-metolachlor. Three multi-year field experiments were conducted at newly planted orchards in the Willamette Valley during 2019 and 2020. Treatments compared pyroxasulfone (0.24 kg ai ha–1), pronamide (2.3 kg ai ha–1), and S-metolachlor (1.39 kg ai ha–1) applied at the reference rate, and at 2× and 4× that rate, compared to weed-free check. Treatments were applied within 2 wk after the winter transplant and reapplied the following year. Hazelnuts showed a high tolerance to all herbicides tested, with negligible injury noted (<3%). No changes in leaf chlorophyll were noted, averaging 242, 179, and 225 mg m–2 on each study site. Tree growth was similar among treatments as measured by trunk cross-sectional area, canopy volume, and internode length. A separate study evaluated the control of Italian ryegrass. Pronamide and pyroxasulfone provide 100% control of Italian ryegrass, and weed dry weight was reduced by up to 79 % compared to the grower standard. This study documents that hazelnuts are tolerant to pronamide, pyroxasulfone, and S-metolachlor, and that these herbicides can improve weed management in young orchards.

Research Article
Creative Commons
This is a work of the US Government and is not subject to copyright protection within the United States. Published by Cambridge University Press on behalf of the Weed Science Society of America.
© Oregon State University, 2022

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Associate Editor: Peter J. Dittmar, University of Florida


Ali, A, Streibig, JC, Duus, J, Andreasen, C (2013) Use of image analysis to assess color response on plants caused by herbicide application. Weed Technol 27:604611 CrossRefGoogle Scholar
Anonymous (2021a) Kerb SC ® FIFRA Section 24(c) Special Local Need (SLN) Label. Agriscience C No. R361-038. Indianapolis, IN 46268.Google Scholar
Anonymous (2021b) Kerb SC® herbicide product label. Agriscience C No. CD02-398-021. Indianapolis, IN 46268.Google Scholar
Beckie, HJ, Reboud, X (2009) Selecting for weed resistance: herbicide rotation and mixture. Weed Technol 23:363370 CrossRefGoogle Scholar
Bobadilla, LK, Hulting, AG, Berry, PA, Moretti, ML, Mallory-Smith, C (2021) Frequency, distribution, and ploidy diversity of herbicide-resistant Italian ryegrass (Lolium perenne spp. multiflorum) populations of western Oregon. Weed Sci 69:177185 Google Scholar
Bollman, SL, Sprague, CL (2008) Tolerance of 12 sugarbeet varieties to applications of S-metolachlor and dimethenamid-P. Weed Technol 22:699706 Google Scholar
Bond, JA, Eubank, TW, Bond, RC, Golden, BR, Edwards, HM (2014) Glyphosate-resistant Italian ryegrass (Lolium perenne ssp. multiflorum) control with fall-applied residual herbicides. Weed Technol 28:361370 CrossRefGoogle Scholar
Boyd, NS, Reed, T (2016) Strawberry tolerance to bed-top and drip-applied preemergence herbicides. Weed Technol 30:492498 CrossRefGoogle Scholar
Brooks, ME, Kristensen, K, van Benthem, KJ, Magnusson, A, Berg, CW, Nielsen, A, Skaug, HJ, Machler, M, Bolker, BM (2017) glmmTMB balances speed and flexibility among packages for zero-inflated generalized linear mixed modeling. The R Journal 9:378400 CrossRefGoogle Scholar
Demoeden, P (1994) Perennial ryegrass control in bermudagrass and zoysiagrass. J Turfgrass Manag 1:3147 CrossRefGoogle Scholar
Evans, JA, Tranel, PJ, Hager, AG, Schutte, B, Wu, C, Chatham, LA, Davis, AS (2016) Managing the evolution of herbicide resistance. Pest Manag Sci 72:7480 CrossRefGoogle ScholarPubMed
Faircloth, WH, Patterson, MG, Foshee, WG, Nesbitt, ML, Goff, WD (2007) Comparison of preemergence and postemergence weed control systems in newly established pecan. Weed Technol 21:972976 CrossRefGoogle Scholar
Ferreira, T, Rasb, W (2012) ImageJ user guide: IJ 1.46 r. Accessed: July 9, 2021Google Scholar
[HRAC] Herbicide Resistance Action Committee (2022) Mode of action classification map. Accessed: February 5, 2022Google Scholar
Hill, RJ, King, DR, Zollinger, R, Moretti, ML (2021) 1-Naphthaleneacetic acid (NAA) reduces sucker growth in European hazelnut (Corylus avellana L.). HortScience 56:15941598 Google Scholar
Horgan, BP, Yelverton, FH (2001) Removal of perennial ryegrass from overseeded bermudagrass using cultural methods. Crop Sci 41:118126 Google Scholar
Hulting, AG, Dauer, JT, Hinds-Cook, B, Curtis, D, Koepke-Hill, RM, Mallory-Smith, C (2012) Management of Italian ryegrass (Lolium perenne ssp. multiflorum) in western Oregon with preemergence applications of pyroxasulfone in winter wheat. Weed Technol 26:230235 CrossRefGoogle Scholar
Jhala, AJ, Ramirez, AH, Singh, M (2013) Tank mixing saflufenacil, glufosinate, and indaziflam improved burndown and residual weed control. Weed Technol 27:422429 Google Scholar
Kaya-Altop, E, Haghnama, K, Sarıaslan, D, Phillippo, CJ, Mennan, H, Zandstra, BH (2016) Long-term perennial weed control strategies: economic analyses and yield effect in hazelnut (Corylus avellana). Crop Protect 80:714 CrossRefGoogle Scholar
Kniss, A, Streibig, J (2020) Statistical analysis of agricultural experiments using R. Accessed: January 20, 2021Google Scholar
Kurtenbach, ME, Johnson, EN, Gulden, RH, Willenborg, CJ (2019) Tolerance of flax (Linum usitatissimum) to fluthiacet-methyl, pyroxasulfone, and topramezone. Weed Technol 33:509517 CrossRefGoogle Scholar
Lenth, R (2019) Emmeans package: estimated marginal means, aka least-squares means. R package version Accessed: July 9, 2021Google Scholar
Lueck, AB, Peters, TJ, Lystad, AL (2020) Environment influences sugarbeet tolerance to S-metolachlor. Weed Technol 34:597606 CrossRefGoogle Scholar
McNaughton, KE, Shropshire, C, Robinson, DE, Sikkema, PH (2014) Soybean (Glycine max) tolerance to timing applications of pyroxasulfone, flumioxazin, and pyroxasulfone+ flumioxazin. Weed Technol 28:494500 Google Scholar
Mennan, H, Bozoğlu, M, Başer, U, Brants, I, Belvaux, X, Kaya-Altop, E, Zandstra, BH (2020) Impact analysis of potential glyphosate regulatory restrictions in the European Union on Turkish hazelnut production and economy. Weed Sci 68:223231 CrossRefGoogle Scholar
Moretti, ML (2021) POST control of Italian ryegrass in hazelnut orchards. Weed Technol 35:638643 CrossRefGoogle Scholar
Moretti, ML (2022) Quick reference guide to herbicides labeled for use in hazelnuts, in Peachey, ER, ed. Pacific Northwest Weed Management Handbook [online]. Corvallis: Oregon State Univ. Scholar
Peters, TJ, Lueck, AB, Carlson, AL (2019) Sugarbeet tolerance when dimethenamid-P follows soil-applied ethofumesate and S-metolachlor. Weed Technol 33:431440 CrossRefGoogle Scholar
RStudio Team (2022) RStudio: Integrated Development R. RStudio, Inc. Accessed: April 22, 2022Google Scholar
Šidák, Z (1967) Rectangular confidence regions for the means of multivariate normal distributions. J Am Stat Assoc 62:626633 Google Scholar
Sikkema, PH, Shropshire, C, Soltani, N (2009) Response of dry bean to pre-plant incorporated and pre-emergence applications of S-metolachlor and fomesafen. Crop Protect 28:744748 CrossRefGoogle Scholar
Sikkema, SR, Soltani, N, Sikkema, PH, Robinson, DE (2008) Tolerance of eight sweet corn (Zea mays L.) hybrids to pyroxasulfone. HortScience 43:170172 CrossRefGoogle Scholar
Smith, MW (2011) Pecan production increased by larger vegetation-free area surrounding the tree. Scientia horticulturae 130:211213 CrossRefGoogle Scholar
Smith, SC, Jennings, KM, Monks, DW, Schultheis, JR, Reberg-Horton, SC (2019) Tolerance of sweetpotato to herbicides applied in plant propagation beds. Weed Technol 33:147152 CrossRefGoogle Scholar
Soil Survey Staff (2022) Natural Resources Conservation Service, United States Department of Agriculture. Web Soil Survey. Accessed: January 10, 2022Google Scholar
Swanton, CJ, Nkoa, R, Blackshaw, RE (2015) Experimental methods for crop–weed competition studies. Weed Sci 63:211 CrossRefGoogle Scholar
[UC IPM] University of California Division of Agriculture and Natural Resources–Integrated Pest Management Program (2022) Herbicide Symptoms. Accessed: February 8, 2022Google Scholar
[USDA] United States Department of Agriculture (2021) Fruit and Tree Nuts Yearbook Tables. Accessed: February 4, 2022Google Scholar