1998 California

Walnut Objective

Measurement Survey Results

Released: September 4, 1998

 12:00 NOON PDT

 CALIFORNIA AGRICULTURAL

 STATISTICS SERVICE

WALNUT PRODUCTION FORECAST

The 1998 California walnut production forecast is 220,000

tons, down 18 percent from 1997's production of 269,000

tons. This is 14 percent below the July forecast of 255,000.

the September forecast is based on the Walnut Objective

Measurement (O.M.) Survey, while the July forecast was

based on subjective information provided by growers. The

Objective Measurement Survey was conducted August 3

through August 29, 1998. Due to a very wet spring, the crop

is about three weeks behind normal. The early varieties, such

as Serr, look to be strong. Mid-season varieties, such as

Vina, are expected to be about average, while late varieties,

such as Hartley and Chandler, look to be off quite a bit from

last year. Levels of sunburn are expected to be higher than

last year.

The 1998 Objective Measurement Survey utilized a total of

731 blocks with two sample trees per block. Survey data

indicated an average nut set of 1,407, down 20 percent from

1997's average of 1,753. The Hartley nut set was down 35

percent; Serr, up 104 percent; Franquette, down 30 percent;

Chandler, down 17 percent from 1997. Percent of sound

kernels in-shell was 94.4 percent Statewide. In-shell weight

per nut was 21.4 grams, while the average in-shell suture

measurement was 31.9 millimeters. The average length inshell was 39.5 millimeters.

Estimated nut sets, sizing measurements, average number of

trees per acre, and estimated bearing acreage were used in

the regression formulas.

SURVEY HISTORY

The Walnut Objective Measurement Survey began in 1958 to

fulfill industry needs for an accurate walnut production

forecast prior to harvest. The original sample was chosen

proportionally to county and variety of bearing acreage. With

each succeeding year, additions and deletions have been

made in the sample to adjust for acreage removed, new

bearing acreage and refusals.

SAMPLING PROCEDURES

Once a block is randomly selected and permission is granted,

two trees are randomly selected. An accessible branch is

chosen which is 5 to 15 percent of the total cross-sectional

area of the primary limbs and reachable with a twelve-foot

ladder. Measurements are made on the trunk, each primary,

and each split leading to and including the accessible branch.

The sample tree and accessible branch are marked by a

single tag.

On the accessible branch, every first of five nuts is picked for

use in size and grade determinations. If available, at least ten

nuts are harvested from the accessible branch for this

purpose.

The following measurements are made on nuts selected for

sizing:

1. Weight of nut including hull.

2. Width of shell at suture.

3. Width of shell 90 degrees to suture line (cross-suture).

4. Length of shell.

5. Kernel grade.

6. Weight of nut in-shell.

DATA RELIABILITY

The 80 percent confidence interval is from 200,000 tons to

240,000 tons. This means there is an 80 percent chance the

1998 production will fall within this range.
- 2 -

TABLE 1 -- California English Walnut Acreage, Production, Price And Value In-Shell

Year Bearing Acres a/ Total Production Per Bearing Acre Price Per Ton Total Value

- - Tons - - - - Dollars - -

1987 176,000 247,000 1.40 984.00 243,048,000

1988 177,000 209,000 1.18 922.00 192,698,000

1989 179,000 229,000 1.28 1,070.00 245,030,000

1990 181,000 227,000 1.25 1,040.00 236,080,000

1991 181,000 259,000 1.43 1,060.00 274,540,000

1992 178,000 203,000 1.14 1,410.00 286,230,000

1993 176,000 260,000 1.48 1,390.00 361,400,000

1994 171,000 232,000 1.36 1,030.00 238,960,000

1995 176,000 234,000 1.33 1,400.00 327,600,000

1996 176,000 208,000 1.18 1,570.00 326,600,000

1997 b/ 177,000 269,000 1.52 1,310.00 352,400,000

1998 177,000 220,000 1.24 7/99 7/99

a/ Bearing years include plantings of the following: Chandler, Chico, Howard, Tulare (1994 & Earlier); 50-55, 59-124, 4946, Amigo, Ashley,

Bardoni, Cisco, Earhorn, Grove, Gustine, Honeycutt, Houston, Jensen, Lompoc, Marchetti, Nuggett, Payne, Pedro, Serr, Sunland, Tehama,

Trinta, UCD 67-13, Vina, Westside (1993 and Earlier); Franquette, Franquette Scharsch, Mayette, Placentia, Poe, Willsons/Willsons Wonder,

Woodland (1991 & Earlier); all other varieties not specified (1992 & Earlier).

b/ Price Per Ton and Total Value are July 1, 1998 preliminary figures.

TABLE 2 -- Walnut Acreage By County As Of 1997

County Bearing Non-Bearing Total

Alameda 94 0 94

Amador 564 30 594

Butte 17,108 1,903 19,011

Calaveras 716 18 734

Colusa 4,641 139 4,780

Contra Costa 1,035 69 1,104

El Dorado 260 1 261

Fresno 3,089 418 3,507

Glenn 6,021 1,585 7,606

Kern 1,440 18 1,458

Kings 5,450 1,137 6,587

Lake 6,364 94 6,458

Madera 968 63 1,031

Mendocino 84 3 86

Merced 5,325 673 5,999

Monterey 327 0 328

Napa 192 29 222

Placer 1,552 0 1,552

Sacramento 117 2 119

San Benito 2,739 135 2,874

San Joaquin 27,143 3,327 30,470

San Luis Obispo 2,823 113 2,936

Santa Barbara 753 13 767

Santa Clara 563 24 587

Shasta 938 36 974

Solano 4,199 688 4,887

Sonoma 225 20 244

Stanislaus 19,346 2,986 22,332

Sutter 14,316 1,724 16,040

Tehama 11,391 1,125 12,516

Tulare 22,451 3,044 25,495

Ventura 250 0 250

Yolo 8,044 945 8,989

Yuba 6,595 552 7,147

Other Counties 83 0 83

STATE 177,206 20,913 198,120

TABLE 3 -- Walnut Acreage By Variety As Of 1997

County Bearing Non-Bearing Total

Ashley 8,898 63 8,961

Chandler 24,850 13,283 38,142

Eureka 6,365 156 6,521

Franquette 13,694 378 14,072

Hartley 51,853 2,148 54,000

Payne 14,997 481 15,478

Serr 22,005 1,146 23,151

Tehama 5,706 42 5,748

Vina 13,278 1,202 14,480

All Others 15,551 2,014 17,565

CROP TOTAL 177,206 20,913 198,119

Percentages in the pie chart do not add to 100 due to rounding.
- 3 -

TABLE 4 -- Walnut Objective Measurement Survey Data, By District

Measurement Year Coast 1/ Sacramento Valley 2/ San Joaquin Valley 3/ State 4/

In-Shell Weight (gm) 1987 20.7 22.5 20.9 21.5

1988 20.6 22.0 20.5 21.2

1989 19.7 22.0 21.4 21.5

1990 21.3 21.8 21.9 21.8

1991 20.7 22.1 19.6 20.8

1992 21.4 23.8 21.6 22.7

1993 23.5 23.7 21.7 22.9

1994 20.9 23.6 20.7 22.1

1995 19.8 21.3 20.3 20.8

1996 20.0 24.4 19.9 22.1

1997 20.9 23.7 22.2 22.9

1998 21.2 22.4 20.3 21.4

In-Shell Width (mm) 1987 31.9 33.0 32.6 32.7

1988 31.7 32.6 32.6 32.5

1989 31.2 32.3 32.7 32.3

1990 31.5 31.9 33.0 32.3

1991 31.1 31.4 31.7 31.5

1992 32.1 32.7 32.6 32.6

1993 32.2 32.4 32.9 32.6

1994 31.4 32.4 32.2 32.2

1995 30.6 31.7 32.0 31.7

1996 31.4 32.5 32.2 32.3

1997 32.3 33.0 31.1 32.3

1998 31.4 32.2 31.5 31.9

In-Shell Cross-Width (mm) 1987 32.2 33.8 32.9 33.2

1988 32.3 32.9 32.4 32.7

1989 32.0 33.0 32.2 32.6

1990 31.6 32.3 32.7 32.4

1991 30.5 31.2 31.2 31.1

1992 32.5 33.1 32.8 32.9

1993 32.0 32.3 32.9 32.5

1994 31.3 32.4 32.3 32.2

1995 30.2 31.3 31.7 31.3

1996 31.4 32.6 32.5 32.5

1997 32.3 33.2 31.9 32.6

1998 31.2 32.1 31.5 31.8

In-Shell Length (mm) 1987 38.9 40.2 39.5 39.7

1988 39.0 39.4 38.9 39.1

1989 38.2 39.1 39.3 39.1

1990 38.5 38.3 39.5 38.8

1991 38.9 39.0 39.1 39.0

1992 39.0 39.7 39.5 39.5

1993 39.9 40.1 39.8 40.0

1994 38.7 39.7 39.3 39.4

1995 39.2 39.0 39.5 39.2

1996 38.4 39.4 38.7 39.0

1997 38.2 39.4 37.6 38.6

1998 39.1 40.0 39.0 39.5

Kernel Grade -- 1987 99.1 97.9 96.6 97.3

Percent Sound 1988 88.7 97.8 95.9 96.2

1989 94.4 97.8 96.8 97.0

1990 96.1 97.1 95.4 96.3

1991 97.3 96.6 94.1 95.5

1992 93.6 96.9 97.6 96.9

1993 93.2 95.2 97.2 95.8

1994 92.6 94.7 97.5 95.6

1995 89.2 91.4 96.1 93.1

1996 92.6 93.8 95.3 94.4

1997 97.8 97.4 97.3 97.3

1998 79.9 93.2 98.3 94.4

Nuts Set Per Tree 1987 1,883 2,696 2,143 2,320

1988 1,359 2,390 1,837 2,008

1989 1,427 2,182 1,537 1,785

1990 1,637 2,380 1,835 2,028

1991 1,955 2,620 2,210 2,340

1992 1,567 1,902 1,380 1,604

1993 1,530 2,703 1,596 2,068

1994 1,813 1,961 1,602 1,773

1995 1,420 2,253 1,451 1,777

1996 1,362 1,836 1,497 1,630

1997 1,128 2,233 1,439 1,753

1998 1,070 1,654 1,253 1,407

1/ Coast includes: Contra Costa, Lake, Monterey, Napa, San Benito, San Luis Obispo, Santa Clara, and Sonoma counties.

2/ Sacramento Valley includes: Butte, Colusa, El Dorado, Glenn, Sacramento, Solano, Sutter, Tehama, Yolo, and Yuba counties.

3/ San Joaquin Valley includes: Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare counties.

4/ District and State averages are derived by weighting county averages by county bearing acreage figures. 
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TABLE 5 -- Walnut Objective Measurement Survey Data, By Variety

Measurement Year Ashley Chandler Eureka Franquette Hartley Payne Serr Tehama Vina Other

In-Shell Weight (gm) 1987 20.3 N/A 23.1 19.7 23.7 19.3 20.5 22.1 18.8 22.1 

1988 18.7 N/A 21.9 19.7 23.4 19.3 20.9 19.0 19.5 21.3 

1989 19.1 24.8 21.0 20.4 24.7 20.4 19.6 21.5 20.1 20.2 

1990 19.5 23.2 22.1 19.9 23.7 20.5 20.9 19.8 19.4 20.7 

1991 18.7 22.8 20.1 19.2 23.4 18.2 18.7 20.3 18.8 19.9 

1992 19.1 24.9 22.3 20.7 25.5 19.4 21.4 21.8 20.5 19.9 

1993 19.8 23.5 21.7 21.2 25.2 20.8 20.8 20.3 20.2 21.7 

1994 19.3 24.3 20.9 20.3 24.7 19.7 20.0 21.1 19.7 21.0 

1995 18.0 20.7 19.1 18.6 23.1 19.5 18.6 18.7 18.4 19.3 

1996 20.0 23.3 20.6 20.1 24.8 18.1 19.8 21.2 20.1 21.1 

1997 19.8 24.4 23.2 21.1 24.8 20.4 21.3 20.5 20.5 22.2 

1998 19.2 21.9 20.8 20.2 24.0 19.6 19.5 19.5 19.2 19.9 

In-Shell Width (mm) 1987 32.6 N/A 32.4 31.1 33.6 32.5 34.2 33.8 30.9 32.6 

1988 32.0 N/A 31.4 30.9 33.5 32.4 34.1 31.8 31.2 32.2 

1989 31.9 33.1 31.2 31.0 33.7 32.1 33.0 32.8 31.3 31.5 

1990 32.3 32.8 31.1 30.7 33.1 33.0 34.2 31.4 30.0 31.4 

1991 31.4 31.9 30.4 30.0 32.4 31.6 32.7 32.0 29.8 30.3 

1992 32.0 33.3 31.6 30.9 33.6 32.3 34.1 33.1 31.3 31.0 

1993 32.3 32.5 30.9 31.3 33.2 33.3 33.6 31.5 30.5 31.6 

1994 31.8 32.7 30.9 30.8 33.2 32.1 33.3 32.4 30.5 30.8 

1995 31.0 31.7 30.6 30.1 32.6 31.9 32.4 31.6 29.7 30.6 

1996 31.7 32.4 31.6 31.1 33.0 32.2 33.0 32.3 30.9 31.2 

1997 31.8 32.3 30.7 30.6 33.3 31.5 33.3 32.0 31.0 30.8 

1998 31.2 31.8 30.2 30.7 33.0 31.4 32.1 31.2 30.6 31.1 

In-Shell Cross-Width (mm) 1987 33.2 N/A 32.7 32.0 34.0 32.7 33.4 34.1 32.7 33.5 

1988 32.1 N/A 32.1 31.4 33.4 32.5 33.5 31.6 32.1 32.9 

1989 31.8 33.9 31.0 31.8 34.1 31.8 32.4 32.6 32.2 32.4 

1990 32.3 32.8 31.2 31.1 33.1 32.8 33.4 31.5 31.1 32.3 

1991 30.7 32.3 30.5 30.1 32.1 30.7 30.7 31.0 30.2 30.5 

1992 32.0 34.3 32.4 31.6 33.9 32.1 33.0 33.0 32.6 32.1 

1993 32.2 32.9 31.7 31.4 33.0 33.0 32.7 31.3 30.8 32.1 

1994 31.6 33.2 31.4 31.3 33.0 31.9 32.3 31.9 31.6 31.9 

1995 30.6 31.7 30.5 30.1 32.1 31.3 30.9 30.7 30.1 31.0 

1996 31.7 33.1 32.1 31.5 32.9 32.2 32.1 32.5 32.1 32.3 

1997 31.9 33.0 32.2 31.3 33.2 32.0 33.0 32.1 32.1 32.0 

1998 31.2 30.9 30.5 31.2 32.5 31.4 31.6 30.8 30.8 31.7 

In-Shell Length (mm) 1987 38.7 N/A 44.0 38.2 40.3 38.1 39.5 39.4 39.2 41.4 

1988 37.3 N/A 43.0 38.6 39.6 37.6 39.1 37.5 39.1 40.5 

1989 37.3 40.8 42.5 38.4 40.1 37.6 38.1 38.8 39.3 39.3 

1990 36.9 39.7 42.6 37.5 39.7 38.1 38.9 37.1 37.3 38.4 

1991 36.7 39.9 43.3 38.2 39.8 37.2 37.4 36.8 38.6 39.2 

1992 37.2 40.5 42.8 37.9 40.6 38.0 38.8 38.3 39.3 38.7 

1993 37.5 40.2 42.5 39.6 41.1 39.2 37.7 37.0 38.9 39.8 

1994 37.1 40.9 43.0 38.7 40.3 37.9 37.9 38.0 38.6 39.2 

1995 36.8 39.6 41.2 38.8 40.1 38.4 37.5 37.8 38.6 38.6 

1996 37.0 39.4 41.4 38.6 40.0 37.8 37.3 37.6 38.8 39.2 

1997 36.2 39.2 41.0 37.8 39.5 36.6 37.4 37.2 38.1 38.5 

1998 37.2 40.0 40.8 39.6 40.9 38.0 37.7 37.7 38.4 39.6 

Kernel Grade -- 1987 95.1 N/A 98.1 98.1 97.4 96.2 96.7 98.5 97.8 97.6 

Percent Sound 1988 94.3 N/A 97.9 95.1 98.1 93.2 94.9 95.0 97.6 97.1 

1989 97.3 98.3 93.9 97.8 97.5 95.2 97.0 97.2 98.7 96.8 

1990 96.6 99.5 94.2 96.7 97.7 94.5 91.0 98.5 94.1 96.8 

1991 91.0 99.9 87.1 97.2 96.1 94.7 94.2 96.7 98.1 98.5 

1992 94.7 99.2 96.1 96.7 97.2 95.4 96.5 99.1 98.0 96.9 

1993 89.8 99.0 92.5 93.9 97.4 94.0 95.3 94.5 94.9 94.8 

1994 91.3 96.6 95.7 95.7 95.3 96.9 96.9 96.4 94.0 97.3 

1995 91.6 93.6 93.4 89.8 93.8 95.2 95.6 88.7 92.4 93.5 

1996 92.3 95.1 93.4 89.8 95.1 95.4 96.6 92.7 95.8 94.2 

1997 96.2 97.8 94.9 96.6 98.1 96.5 97.0 96.7 97.5 96.6 

1998 94.4 91.4 99.8 89.5 94.4 96.3 97.9 94.3 95.2 95.2 

Nuts Set Per Tree 1987 2,029 N/A 2,633 3,267 2,595 1,853 1,204 2,031 2,561 2,424 

1988 1,599 N/A 1,789 2,482 2,414 1,885 1,084 2,224 2,006 1,799 

1989 1,338 2,761 2,051 2,411 1,767 1,543 1,603 1,461 1,645 1,877 

1990 1,399 2,716 2,058 2,706 2,662 1,648 884 1,683 2,216 1,708 

1991 1,372 3,092 3,212 3,116 2,712 2,067 1,553 1,487 2,055 2,161 

1992 1,072 1,645 1,585 2,012 2,008 1,487 915 1,082 1,385 1,626 

1993 1,147 2,099 1,452 2,532 2,742 1,444 1,626 1,653 1,654 1,818 

1994 1,391 1,711 1,905 2,781 1,974 1,540 1,154 1,207 1,619 1,643 

1995 1,392 1,912 1,590 2,348 2,284 1,404 984 1,961 1,260 1,157 

1996 1,353 1,659 1,296 2,356 1,853 1,285 1,417 958 1,355 1,472 

1997 1,406 1,570 1,414 2,162 2,228 1,304 796 1,703 1,894 1,839 

1998 1,221 1,306 1,380 1,512 1,457 1,170 1,622 1,347 1,504 1,290 
TABLE 6 -- Percentage Distribution Of Walnut Shell Suture Sizes, By District And Variety

District

And

Variety

U.S. Standards Size Intervals 1/

1994 1995 1996 1997 

Mth Jmb Lge Med Bby Oth Mth Jmb Lge Med Bby Oth Mth Jmb Lge Med Bby Oth Mth Jmb Lge Med Bby Oth 

- - - - - - - - - - - - - - - Percent of Total 2/ - - - - - - - - - - - - - - -

DISTRICTS:

 Coast 1 47 16 15 19 1 0 36 16 20 26 1 0 47 20 15 17 1 1 62 16 9 12 0  Sacramento Valley 0 64 12 12 10 1 0 53 16 14 15 1 0 65 14 11 9 0 0 73 11 9 6 0  San Joaquin Valley 0 60 18 13 9 0 0 59 17 13 10 1 0 61 18 12 8 0 0 51 14 12 19 4 

VARIETIES:

 Ashley 0 54 18 16 12 0 0 42 22 18 18 1 0 54 17 13 15 1 0 62 15 9 10 4  Chandler 0 69 17 9 5 0 1 52 19 19 10 0 1 67 16 9 7 0 1 67 11 10 10 1  Eureka 0 28 38 20 13 0 0 29 30 22 17 1 0 49 29 12 10 0 0 36 29 12 20 2  Franquette 0 39 21 18 21 1 0 24 21 24 28 2 0 41 25 17 16 1 0 35 19 21 23 1  Hartley 0 78 10 7 4 0 0 69 13 9 8 0 0 74 12 9 5 0 0 79 9 5 5 1  Payne 1 56 17 15 9 1 0 59 15 15 11 1 0 62 16 11 10 1 0 55 13 12 19 2  Serr 1 78 9 7 5 0 0 66 16 10 6 1 1 75 11 7 5 0 1 75 8 8 7 1  Tehama 0 66 12 11 10 0 1 53 15 15 16 1 0 59 22 11 7 0 0 61 15 11 14 0  Vina 0 30 22 26 21 1 1 25 16 22 31 5 0 38 19 22 20 1 0 45 18 18 15 3  Other 0 38 15 24 21 1 0 40 14 18 27 1 1 46 16 18 18 1 1 43 17 15 18 7  STATE 0 60 15 13 10 1 0 54 16 14 14 1 0 62 16 11 9 0 0 64 13 10 11 2 Number of Shells Measured 12,215 12,558 13,242 13,220 

1/ Sizes used are as follows: Mammoth -- Larger than 96/64" in diameter; Jumbo -- 80/64" to 96/64"; Large -- 76/64" to 80/64" for Eureka variety, 77/64" to 80/64" for all other 

for Eureka, 73/64" to 77/64" for all others; Baby -- 60/64" to 73/64"; and Others -- below 60/64".

2/ Percentage distributions based upon nut samples taken in the field, may not equal 100 percent due to rounding.