Almond Rootstock Options for High Boron Conditions

23 Pages·2017·1.8 MB·English

by  Robin Walton

Almond Rootstock
Options for High
Boron Conditions
Kat Pope
Orchard Advisor,
Sac-Solano-Yolo
February 7th, 2017
Talk outline
• Almond boron basics
• Almond rootstock trial results: yields, what
may be driving yield differences, practical
take-aways
• Triage for what’s already planted
Top Three
• 2,000+ lbs/ac is possible in high B conditions
IF you pick the right rootstock. (6th leaf)
• Lovell and Krymsk 86 yield low in high B
conditions.
• If a not great rootstock is already in the
ground, leach in the winter, set a crop early
and watch for Bot.
Boron Toxicity
in Almond
•No leaf symptoms.
•Brown-black dead lesions
on bark
•Tip die-back
•Boron accumulation in fruit
•Gumming on fruits and bark
•Increased stick tights
Slide Credit: Patrick Brown
Rootstock Trial Site and Set-Up
Marvin silty clay loam
41% clay, 48% silt
Water: <1 - 3.1 mg/l B
Soil: 1.3-2.2 mg/l B
Credit & Thanks:
9 Rootstocks w/ Nonpareil
Host: Dave Scheuring, Gold Oak Ranch
Funding: Almond Board of California
Nursery grafted
All Bareroot except Brights
Planted: Feb, 2011
(Titan Apr 2011 not rep’d)
Spacing: 22’ x 18’ (110 trees/ac)
Rootstock Trial Site and Set-Up
Marvin silty clay loam
Rootstock Origin
41% clay, 48% silt
Titan SG1 Peach-Almond
Water: <1 - 3.1 mg/l B
FxA Peach-Bitter Almond
Soil: 1.3-2.2 mg/l B
Nickels Peach-Almond
9 Rootstocks w/ Nonpareil Brights 5 Peach-Almond
Hansen 536 Peach-Almond
Nursery grafted
Rootpac-R Myro Plum-Almond
All Bareroot except Brights
Viking Pch-Alm-Myro-Apr
Planted: Feb, 2011
Krymsk 86 Myro Plum-Peach
(Titan Apr 2011 not rep’d)
Lovell Peach
Spacing: 22’ x 18’
Rootstock Trial Site and Set-Up
Marvin silty clay loam
Rootstock Origin
41% clay, 48% silt
Titan SG1 Peach-Almond
Water: <1 - 3.1 mg/l B
FxA Peach-Bitter Almond
Soil: 1.3-2.2 mg/l B
Nickels Peach-Almond
9 Rootstocks w/ Nonpareil Brights 5 Peach-Almond
Hansen 536 Peach-Almond
Nursery grafted
Rootpac-R Myro Plum-Almond
All Bareroot except Brights
Viking Pch-Alm-Myro-Apr
Planted: Feb, 2011
Krymsk 86 Myro Plum-Peach
(Titan Apr 2011 not rep’d)
Lovell Peach
Spacing: 22’ x 18’
Yield Varied with Rootstock
2,500
2015 2016
a
a
2,000
ab
e
r
c bc
A
1,500
r
e
P cd

s de
b
L

l1,000
e ef
n
r
e f
K
500
0
Yield Varied with Rootstock
2,500
2015 2016
a
a
2,000
ab
e
r
c bc
A
1,500
r
e
P cd

s de
b
L

l1,000
e ef
n
r
e f
K
500
0
Yield Varied with Rootstock
2,500
2015 2016
a
a
2,000
ab
e
r
c bc
A
1,500
r
e
P cd

s de
b
L

l1,000
e ef
n
r
e f
K
500
0