1997 California

Walnut Objective

Measurement Survey Results

Released: September 5, 1997

 12:00 NOON PDT

 CALIFORNIA AGRICULTURAL

 STATISTICS SERVICE

WALNUT PRODUCTION FORECAST

The 1997 California walnut production forecast is 230,000 tons, up 11

percent from 1996's production of 208,000 tons. This is unchanged from

the July forecast. The July forecast was based on subjective information

provided by growers, while the September forecast is based on the

Walnut Objective Measurement (OM) Survey. The Objective

Measurement Survey was conducted July 28 through August 23, 1997.

 Due to an earlier than usual spring, the crop is ahead of normal. Mild

temperatures have resulted in the highest percent of sound nuts in the

last ten years. OM samples show low levels of sunburn and insect

damage.

The 1997 Objective Measurement Survey utilized a total of 678 blocks

with two sample trees per block. Survey data indicated an average nut

set of 1,753, up 8 percent from 1996's average of 1,630. The Hartley nut

set was up 20 percent; Serr, down 44 percent; Franquette, down 8

percent from 1996. Percent of sound kernels in-shell was 97.3 percent

Statewide. In-shell weight per nut was 22.9 grams, while the average inshell suture measurement was 32.3 millimeters. The average length inshell was 38.6 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 213,000 tons to 247,000 tons.

This means there is an 80 percent chance the 1997 production will fall

within this range.

1997 SEPTEMBER WALNUT SUBJECTIVE SURVEY

At industry request, a subjective grower survey was conducted

August 28, 29, and September 2. Useable reports were received

from 145 growers representing approximately 14 percent of the

bearing acres in the State. Two indications were calculated from

the survey. The first is a weighted average yield of all growers

who reported acres and an expected yield for 1997. The

weighted average yield from these growers was 2,501 pounds

per acre (1.25 tons). Multiplying the average yield by the bearing

acres (170,000) gives an indicated production of 213,000 tons.

The second indication is the change in expected yield as

indicated by growers who reported in both the July and

September subjective surveys. Growers who responded to the

July and September surveys stated that their yield will be 96.6

percent of what was reported in July. Applying that percent to the

July indication shows 222,000 tons. 

To ensure the September forecast is comparable with previous

year’s, these indications were not considered in setting the

September forecast. Without history, it is impossible to

determine the relationship between these subjective indications

and the final estimate.
- 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 169,000 234,000 1.38 1,400.00 327,600,000

1996 b/ 169,000 208,000 1.23 1,550.00 322,400,000

1997 170,000 230,000 1.35 7/98 7/98

a/ Eight years and older for the Blackmer, Carmelo, Concord, Franquette, Grove, Mayette, Placentia, Poe, and Pride of Ventura varieties, 6 years and older

for the Amigo, Ashley, Chandler, Gustine, Howard, Lompoc, Midland, Payne, Pedro, Serr, Sunland, Tehama, Trinta, Vina, Westside, and 4946 varieties,

5 years and older for the Chico and Marchetti varieties, and 7 years and older for all other varieties.

b/ Price Per Ton and Total Value are July 1, 1997 preliminary figures.

TABLE 2 -- Walnut Acreage By County As Of 1996

County Bearing Non-Bearing Total

Alameda 90 1 91

Amador 479 70 549

Butte 16,533 2,711 19,244

Calaveras 846 17 863

Colusa 4,508 392 4,900

Contra Costa 1,066 82 1,148

El Dorado 257 1 258

Fresno 2,778 597 3,375

Glenn 5,795 2,011 7,806

Kern 1,411 30 1,441

Kings 4,995 1,588 6,583

Lake 6,309 132 6,441

Madera 845 190 1,035

Mendocino 75 2 77

Merced 4,852 1,270 6,122

Monterey 308 20 328

Napa 186 32 218

Placer 1,434 0 1,434

Sacramento 114 2 116

San Benito 2,578 197 2,775

San Joaquin 26,427 4,689 31,116

San Luis Obispo 2,827 247 3,074

Santa Barbara 723 33 756

Santa Clara 547 40 587

Shasta 1,273 24 1,297

Solano 3,899 908 4,807

Sonoma 238 19 257

Stanislaus 18,120 3,705 21,825

Sutter 12,545 3,036 15,581

Tehama 10,860 1,265 12,125

Tulare 20,491 4,198 24,689

Ventura 235 0 235

Yolo 7,961 1,295 9,256

Yuba 6,610 574 7,184

Other Counties 83 0 83

STATE TOTAL 168,298 29,378 197,676

TABLE 3 -- Walnut Acreage By Variety As Of 1996

County Bearing Non-Bearing Total

Ashley 8,886 130 9,016

Chandler 15,960 18,652 34,612

Eureka 6,744 212 6,956

Franquette 13,828 603 14,431

Hartley 52,665 3,281 55,946

Payne 14,738 707 15,445

Serr 22,643 1,267 23,910

Tehama 5,673 121 5,794

Vina 12,466 1,907 14,373

All Others 14,695 2,498 17,193

CROP TOTAL 168,298 29,378 197,676

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

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

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

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

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

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 

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. 
- 4 -

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 

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 

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 

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 

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 

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 
TABLE 6 -- Percentage Distribution Of Walnut Shell Suture Sizes, By District And Variety

District

And

Variety

U.S. Standards Size Intervals 1/

1993 1994 1995 1996 

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

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

DISTRICTS:

 Coast 4 49 18 16 12 1 1 47 16 15 19 1 0 36 16 20 26 1 0 47 20 15 17  Sacramento Valley 1 65 13 11 10 1 0 64 12 12 10 1 0 53 16 14 15 1 0 65 14 11 9  San Joaquin Valley 1 72 12 10 6 0 0 60 18 13 9 0 0 59 17 13 10 1 0 61 18 12 8 

VARIETIES:

 Ashley 0 63 16 12 9 0 0 54 18 16 12 0 0 42 22 18 18 1 0 54 17 13 15  Chandler 0 64 17 11 7 0 0 69 17 9 5 0 1 52 19 19 10 0 1 67 16 9 7  Eureka 0 39 28 15 18 0 0 28 38 20 13 0 0 29 30 22 17 1 0 49 29 12 10  Franquette 0 46 17 21 14 2 0 39 21 18 21 1 0 24 21 24 28 2 0 41 25 17 16  Hartley 1 77 10 7 5 0 0 78 10 7 4 0 0 69 13 9 8 0 0 74 12 9 5  Payne 4 70 12 8 7 0 1 56 17 15 9 1 0 59 15 15 11 1 0 62 16 11 10  Serr 2 79 7 8 4 0 1 78 9 7 5 0 0 66 16 10 6 1 1 75 11 7 5  Tehama 0 51 20 16 13 1 0 66 12 11 10 0 1 53 15 15 16 1 0 59 22 11 7  Vina 0 36 17 19 24 3 0 30 22 26 21 1 1 25 16 22 31 5 0 38 19 22 20  Other 0 50 17 18 14 1 0 38 15 24 21 1 0 40 14 18 27 1 1 46 16 18 18  STATE 1 66 13 11 9 1 0 60 15 13 10 1 0 54 16 14 14 1 0 62 16 11 9 Number of Shells Measured 11,605 12,215 12,558 13,242 

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 oth

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.