UC researchers plan to plant a new set of regional variety trials for almonds, adding to the growing breadth of information available to growers about yield, kernel quality and growing characteristics of new and experimental varieties of almonds.
In 2014, UC, with funding from Almond Board of California, embarked on a project to evaluate new and experimental varieties produced from UC Davis, USDA and commercial California nurseries. 29 varieties are being tested side-by-side in replicated field trials planted in Madera, Stanislaus and Butte counties.
In Madera County, trees are on Hansen 536 rootstock and planted at a 12’ x 21’ spacing (173 trees per acre). In Stanislaus, trees are on Nemaguard and planted at 16’ x 21’ (130 trees per acre), and in Butte, trees are on Krymsk 86 and planted at 18’ x 22’ (110 trees per acre).
Nonpareil is planted every other row, and the experimental varieties are planted as pollinizers. Each variety is replicated four times in each location, so confidence in the yield data is maximized. At least 14 of the tested varieties are self-fertile, meaning they can be planted in solid blocks with fewer bees, according to UCCE Farm Advisor Roger Duncan, who has overseen the trials since its planting.
Now in their ninth season, Duncan said researchers and growers are starting to get a good idea of yield, kernel defects, disease or growing problems and production timing for these varieties. See results in tables below.
| Variety | Breeder/Nursery | Variety | Breeder/Nursery |
| Self-sterile | Partially Self-fertile | ||
| Eddie | Bright’s | Sweetheart | UC Davis |
| Supareil | Burchell | Winters | UC Davis |
| Sterling | Burchell | ||
| Booth | Burchell | Fully self-fertile | |
| Capitola | Burchell | UCD1-232 | UC Davis |
| Folsom | Dave Wilson | UCD1-271 | UC Davis |
| Bennett-Hickman | Duarte | UCD7-159 | UC Davis |
| Jenette | Fowler | UCD8-160 | UC Davis |
| Durango | Fowler | UCD8-201 | UC Davis |
| Kester | UC Davis | UCD8-27 | UC Davis |
| UCD18-20 | UC Davis | Yorizane | USDA |
| UCD1-16 | UC Davis | Y117-86-03 | USDA |
| UCD3-40 | UC Davis | Y117-91-03 | USDA |
| Aldrich | N/A | Y121-42-99 | USDA |
| Nonpareil | N/A | P16.013 | Burchell |
| P13.019 | Burchell |
|
Average Cumulative Yield for the First Six Harvests, Canopy Size as Measured by Photosynthetically Active Radiation (PAR) and Yield per PAR. |
||||||
|
Cumulative Yield per Acre 3rd – 8th leaf (2016 – 2021) |
Average 2021 PAR |
Average Cumulative Yield / PAR |
||||
|
Average of all 3 Sites |
Butte County |
Stanislaus County |
Madera County |
|||
|
Nonpareil |
14,864 |
16,527 |
11,451 |
16,613 |
71 |
209 |
|
Y117-91-03 |
13,819 |
13,619 |
13,927 |
13,939 |
68 |
203 |
|
UCD 18-20 |
13,686 |
14,232 |
12,015 |
14,812 |
66 |
207 |
|
Booth |
13,054 |
14,035 |
10,834 |
14,292 |
72 |
181 |
|
Aldrich |
12,614 |
14,297 |
11,126 |
12,420 |
64 |
197 |
|
Yorizane |
12,382 |
11,367 |
10,295 |
15,822 |
59 |
210 |
|
Bennett |
12,069 |
11,559 |
11,810 |
12,867 |
64 |
189 |
|
Durango |
12,040 |
12,912 |
10,175 |
12,568 |
67 |
180 |
|
Kester |
11,904 |
11,479 |
10,438 |
13,796 |
69 |
173 |
|
Y117-86-03 |
11,839 |
10,669 |
9,931 |
14,917 |
61 |
194 |
|
Capitola |
11,756 |
11,469 |
9,603 |
14,195 |
72 |
163 |
|
Jenette |
11,553 |
12,885 |
8,618 |
14,134 |
59 |
196 |
|
Winters |
11,422 |
12,075 |
9,979 |
11,850 |
64 |
178 |
|
Eddie |
10,984 |
10,592 |
9,982 |
12,379 |
67 |
164 |
|
UCD 8-160 |
10,930 |
10,627 |
10,307 |
11,856 |
50 |
219 |
|
UCD 8-201 |
10,857 |
10,543 |
9,475 |
12,207 |
59 |
184 |
|
Sterling |
10,662 |
9,831 |
9,681 |
11,983 |
69 |
155 |
|
Folsom |
10,643 |
11,137 |
9,103 |
11,690 |
75 |
142 |
|
UCD 7-159 |
10,255 |
10,469 |
10,440 |
9,724 |
60 |
171 |
|
Supareil |
10,166 |
9,190 |
9,183 |
12,452 |
76 |
134 |
|
Sweetheart |
10,130 |
9,741 |
9,122 |
11,526 |
72 |
141 |
|
UCD 1-16 |
9,545 |
10,209 |
7,381 |
11,044 |
64 |
149 |
|
UCD 1-232 |
9,350 |
9,205 |
9,555 |
9,193 |
57 |
164 |
|
UCD 8-27 |
9,130 |
9,727 |
7,259 |
10,402 |
66 |
138 |
|
UCD 1-271 |
7,721 |
7,175 |
8,653 |
6,948 |
63 |
123 |
|
Bloom and Harvest Dates Before (-) or After (+) Nonpareil |
||
|
Full Bloom +/- NP |
Harvest +/- NP |
|
|
Y117-91-03 |
+3 |
-6 |
|
Eddie |
-1 |
-2 |
|
Y121-42-99 |
+4 |
-1 |
|
Nonpareil |
– |
– |
|
Yorizane |
+2 |
-3 |
|
Kester |
+4 |
+5 |
|
Sterling |
0 |
+6 |
|
Folsom |
+4 |
+7 |
|
Booth |
0 |
+8 |
|
UCD8-201 |
+4 |
+9 |
|
P13.019 |
+4 |
+9 |
|
Capitola |
-2 |
+10 |
|
UCD1-271 |
0 |
+10 |
|
Bennett |
0 |
+11 |
|
Y117-86-03 |
+3 |
+12 |
|
Sweetheart |
+2 |
+15 |
|
UCD1-16 |
-1 |
+16 |
|
UCD8-27 |
-3 |
+18 |
|
UCD7-159 |
-1 |
+19 |
|
Jeanette |
0 |
+24 |
|
Supareil |
-1 |
+24 |
|
Aldrich |
0 |
+24 |
|
Durango |
+1 |
+25 |
|
UCD8-160 |
0 |
+26 |
|
UCD1-232 |
+2 |
+32 |
|
Winters |
-1 |
+33 |
|
UCD18-20 |
+1 |
+33 |
|
P16.013 |
+3 |
+36 |
|
UCD3-40 |
-10 |
+37 |
