The Weekly Tree Nut Report from West Coast Nut arrives every Wednesday with field intelligence for California almond, pistachio and walnut growers and their crop consultants. Subscribe free to get it by email.
Research through October 23, 2026 (Pacific). This week’s priority: build the block-level evidence file. Early Sacramento Valley almond receipts show quality moving in different directions by variety,1 and CDFA’s final report on the 2025 walnut crop puts prices well below 2024.9 The other briefs apply clearly dated UC guidance to dormant-season planning; they do not report new local outbreaks.
This week in numbers
- 1.70%: August Sacramento Valley almond rejects, down from 2.25% in 20251
- 100: Dormant spurs per walnut blight bud sample; the lab plates 303
- 74.6¢: Average finalized price per pound, 2025 walnut crop, vs. 92.6¢ for 20249
For PCAs: Pest, Weed and Disease Management
1. Almonds: separate the reject signal by variety and cause
New since last issue · UCCE and UC IPM, Oct 20, 2026
Sacramento Valley advisors report that August total almond rejects fell from 2.25% in 2025 to 1.70% in 2026, but the varieties diverged: Nonpareil rejects declined from 2.4% to 1.6%, while Independence rose from 1.7% to 2.2%. Nonpareil and Independence made up more than 95% of August receipts, and the authors caution that it is very early to draw firm conclusions about quality for the full season.1
Drawing on trap counts and grower and PCA reports, they offer possible explanations, not confirmed causes: generally lower navel orangeworm pressure than in 2025; “brown spot,” particularly in Independence, which in this region is thought to be largely associated with leaffooted bug feeding; and kernel gumming, whose cause remains unresolved. They suggest gumming may be linked to rapid nut growth in the warm late-February and March weather and, in some orchards, possibly to low boron.1
Next step: Build a variety-by-block reject matrix from processor grade sheets and retained crack-outs. Code worm damage, brown spot and gumming separately, and attach trap trends, treatment timing, harvest date and sanitation history. Don’t treat a reject percentage as a pest diagnosis, or boron as a confirmed fix: base any 2027 boron plan on hull tests reviewed with your CCA. Deliverable: a one-page quality diagnosis for each high-reject block.
Source: UCCE: Sacramento Valley almond crop quality update, 2026
2. Orchard weeds: put johnsongrass timing in the winter plan
Recent update · UCCE, Oct 12, 2026
Orchard trials led by UCCE weed science advisor Ryan Hill (Tehama, Shasta and Glenn counties) treated established johnsongrass on nine application dates across 2024–2026 and rated weed cover eight weeks later. Every timing treatment was a glyphosate plus rimsulfuron tank mix; rimsulfuron alone was not tested. Applications from early March through mid-April gave 76–98% control when rain incorporated them within two weeks, while a late-February 2026 application followed by a month without rain improved control by only 18%.2
The article favors late March to early April for heavily infested orchards and describes rimsulfuron as a rotation component, not a stand-alone program. Treat the results as a timing hypothesis for the tested sites, not a guaranteed result or a product recommendation; California registration and current labels govern use.2
Next step: Map johnsongrass patches and distinguish established clumps from seedlings and look-alike grasses. Build a March–April decision window listing growth stage, rain-incorporation opportunity, prior modes of action and an eight-week evaluation date, and change the plan if spring conditions don’t resemble the trials. Deliverable: a weed-timing and rotation record.
Source: UCCE: application timing and johnsongrass control
3. Walnuts: schedule dormant blight bud sampling
Seasonal reminder · UCCE, Mar 1, 2019; updated Feb 2019
The walnut blight bacterium, Xanthomonas arboricola pv. juglandis, can overwinter inside dormant bud scales. UCCE’s method samples from December through March, or into early April for late-leafing varieties, until buds begin to open: collect 100 dormant spurs with fat terminal buds while walking the whole area, generally one or two buds per tree. Hold samples in paper bags in a cool, dry place; the laboratory plates a 30-bud subsample.3
The article’s low- and high-risk graphs are labeled as examples, not universal action thresholds. Risk also depends on variety, the pathogen population and spring rainfall.3
Next step: Define sampling units before dormancy. Split blocks where variety, blight history or wetness differs, and keep block identity on every bag. Confirm that your laboratory currently offers the bud assay, then reconcile results with 2026 disease maps and spray records. Deliverable: a dormant-bud sampling map and a conditional 2027 blight plan.
Source: UCCE: walnut blight bud sampling
For CCAs: Water and Orchard Floor Management
4. Pistachios: investigate crown decline before the wet season
Research to apply · UC IPM, text updated Nov 2025
UC IPM describes Phytophthora root and crown rot in pistachio as yellowing, defoliation and poor vigor, with cankers below the soil line, gumming and darkened roots and cambium; gum starts light-colored but can turn black once infection reaches the scion. Risk rises with prolonged high soil moisture, poor drainage, hardpans, heavy soils and saline or saline-sodic soils, and canals and rivers are major inoculum sources. Third- and fourth-leaf orchards receiving excessive irrigation are commonly affected, although trees of any age can be killed.4
Management starts with water. UC IPM advises avoiding soil saturation longer than 24 hours and, once roots have grown beyond the root ball and active growth has begun, moving drip emitters away from the trunk to keep the crown dry. Clonal and seedling UCB-1 rootstocks are the most affected; the guideline notes greater Phytophthora tolerance for Platinum than for PG1 or clonal UCB-1, but says Platinum’s susceptibility to Verticillium wilt is unknown.4
Next step: For suspect rows, map crown wetting, set duration, infiltration and restrictive layers, and send ambiguous tissue to a diagnostic lab; gumming alone is not a definitive call. Review emitter placement before chemistry, and keep the Verticillium tradeoff in any replant rootstock recommendation. Deliverable: a decline map, diagnostic result and irrigation-response plan.
Source: UC IPM: Phytophthora root and crown rot in pistachio
5. Almonds: write the cover-crop specification from the objective
Seasonal reminder · UCCE, July 17, 2019; modified Aug 12, 2019
UCCE’s seed-selection guidance is written for non-tilled Sacramento Valley almond orchards that need a clean floor for sweeping and pickup, and for reseeding winter annuals. Grasses generally deliver early growth, nitrogen scavenging and weed competition; legumes add nitrogen and break down faster; brassicas offer thicker rooting for long-term infiltration. Mustards are the main bee forage before almond bloom, but only if seeded and watered up early. Grasses and brassicas decompose more slowly, and sunny young orchards can grow heavy grass, raising the risk the cover won’t break down before harvest.5
Next step: State one primary goal (trafficability, nitrate capture, weed competition, pollinator forage or soil structure), then specify species group, seeding zone, frost constraint and termination standard. Late October is late in the article’s planting window, so confirm seed availability and any cost-share terms before committing. Compare last year’s biomass with sweep and pickup performance. Deliverable: a block-specific seed-mix and termination specification.
Source: UCCE: cover crop seed selection
Market snapshot: Walnut Prices and Shipments
New walnut price report · Shipment figures carried forward
CDFA’s final handler report for the 2025 walnut crop, released October 20, puts the weighted average price at 74.6 cents per pound on 768,457 tons with finalized pricing, down from 92.6 cents on 590,506 tons for the 2024 crop. Chandler averaged 77.7 cents, Howard 68.6 and Tulare 68.1. Another 27,970 tons had not been finalized, at a good-faith estimate of 70.2 cents.9
| Walnut prices 2025 crop · new |
74.6 cents per pound, finalized contracts, versus 92.6 cents for the 2024 crop.9 |
| Pistachios September 2026 |
88.42 million total reported product pounds shipped, versus 63.08 million in September 2025.6 |
| Almonds August–September 2026 |
422.64 million kernel-weight pounds shipped, versus 355.06 million in the same months of 2025.7 |
| Walnut shipments September 2026 |
5,177 inshell short tons versus 2,509; 15,512 kernel short tons versus 9,461, compared with September 2025.8 |
No October shipment reports were out by our research cutoff, so the shipment figures are carried forward from last week’s edition. They measure movement, not grower returns. The Almond Board’s October position report is scheduled for November 12.6–8
Next step: Set the variety spread in the walnut price report against your own settlements before 2027 block decisions; shipment growth does not establish a grower return.
Sources: Walnut price report (PDF) · Pistachio shipments (PDF) · Almond position report (PDF) · Walnut shipments (PDF)
From West Coast Nut magazine
Carpophilus Beetle Continues to Damage Tree Nut Crops
By Cecilia Parsons, Associate Editor · October 13, 2026
Reporting from the Crop Consultant Conference, West Coast Nut follows carpophilus beetle’s spread through San Joaquin and Sacramento Valley tree nut orchards and why winter sanitation remains the foundation of control.
Read the article · Browse the latest issue
What are you seeing?
What is your crop, county and biggest field concern? Email info@jcsmarketinginc.com and tell us.
Editorial note: “Next step” passages are West Coast Nut’s editorial recommendations; the findings before them are attributed to the numbered sources. Product mentions are not recommendations. Orchard-specific judgment, current product labels and applicable requirements govern management. This report does not award CE credit.
Sources
- Franz Niederholzer (UCCE) and Sudan Gyawaly (UC IPM), Sacramento Valley Orchards, “Sacramento Valley almond crop quality update, 2026,” October 20, 2026.
- Ryan Hill, UCCE Sacramento Valley Orchards, “Application timing impacts rimsulfuron efficacy on johnsongrass populations,” October 12, 2026.
- Luke Milliron and Richard P. Buchner (UCCE) and Steve E. Lindow (UC Berkeley), Sacramento Valley Orchards, “Walnut Blight Bud Sampling,” March 1, 2019; updated February 2019.
- F. P. Trouillas and T. J. Michailides, UC Statewide IPM Program, “Phytophthora Root and Crown Rot,” Pistachio Pest Management Guidelines, text updated November 2025.
- Katherine Jarvis-Shean and Dani Lightle, UCCE Sacramento Valley Orchards, “Cover Crop Seed Selection,” July 17, 2019; modified August 12, 2019.
- Administrative Committee for Pistachios, “September 2026 Inventory Shipment Report (Pounds),” October 15, 2026, p. 1.
- Almond Board of California, “Almond Industry Position Report, September 2026,” October 13, 2026, p. 1.
- California Walnut Board, “Monthly Shipment Report, September 2026,” October 8, 2026, pp. 1–2.
- California Department of Food and Agriculture and USDA NASS, “Walnut/Raisin/Prune Report, 2025 Crop Year,” October 20, 2026, p. 2; 2024 figures from the 2024 Crop Year report.