Experiences With GEM Variety Management (and New

Rootstocks).

Consuelo Fernández NogueraBrokaw Nursery LLC

Outline

• History and origin of the cultivar• Experience at Brokaw Ranches• What have we learned through our experience

• Development in other countries• Challenges and uncertainties• A look into the future

History• In 1986 roughly 10,000 seedlings were planted at Bob Lamb’s Camarillo grove by Dr Bob Bergh. • Lamb-Hass, GEM and other selections originated from this Bob Lamb plot. • In 1992 3-29-5 (GEM) was selected and topworked at UC South Coast Research and Extension Center. • In 1994 some material of the new selection was distributed for testing by growers. Hank Brokaw topworked 4 trees for observation.

Brokaw Ranches Experience• 4 trees topworked in 1994 at Cheravo Ranch in Santa Paula for observation and

evaluation.

• An additional 50 trees were topworked in 1999.

Observations:

• Upright, compact growth habit.

• Excellent fruit quality.

• Superior peeling characteristics.

• Larger fruit sizes when compared to Hass.

• Tendency to set fruit in clusters that hang under the tree’s canopy.

• Low alternation.

• Matures slightly later than Hass.

• It hangs well on the tree.

• High yields.

Brokaw Ranches Experience• In 2002 a US Plant Patent application for 3-29-5 (GEM) was

filed.

• Brokaw Nursery was licensed to propagate GEM trees in February 2004.

• Initial sales volumes were very low.

• In 2006 the GEM was included in a high density trial block established by Brokaw Nursery at the Faught Ranch in Santa Paula.

Faught Ranch High Density Trial• Planting Date: August 2006. • Planting Distance: 10’ x 12’.• Berms. • Drip Irrigation(2 lines, 18” between emitters y

0.5 galons/hr).• Girdling (Hass only).• Stakes.• Rootstock Scion combinations:

Hass/ Toro CanyonHass/ DusaCarmen/DusaCarmen /Toro CanyonLeavens Hass/ Toro CanyonLeavens Hass/DusaGEM/ Toro CanyonLamb Hass/Dusa

Faught Ranch High Density Trial• Planting Date: August 2006

• Planting Distance: 10’ x 12’

• Berms

• Drip Irrigation (2 lines, 18” between emitters y 0.5 galons/hr).

• Girdling (Hass only)

• Steaks

• Prunning

• Rootstock Scion combinations:

Hass/ Toro Canyon

Hass/ Dusa

Carmen/Dusa

Carmen /Toro Canyon

Leavens Hass/ Toro Canyon

Leavens Hass/Dusa

GEM/ Toro Canyon

Lamb Hass/Dusa

• GEM was well suited to high density

• This experience with GEM at higher densities increased our enthusiasm for the cv.

Faught Ranch Young Block• Bigger commitment to high densities.• Mainly Hass.• Planting Date: July 2009.• Planting distance: 6’ x 14.5’• Berms.• Drip Irrigation.• Girdling (Hass only).• Stakes.• In 2011 4 rows topworked to GEM.• In 2015 we initiated a progressive

conversion of 6 rows/year to GEM.

Mupu and Cheravo Ranches

• Based on these experiences, Brokaw Ranch Company affirmed a commitment to the GEM variety.• 2013 – 2017: 21 Acres planted with GEM (13,000 trees).

Planting Distances: 5’ x 14.5’ (600 trees/A).Berms.Drip Irrigation (2 lines, 18” between emitters y 0.5 galons/hr).Stake (2’’ diameter and 6’ tall).Irrigation and fertilization for GEM is 20% more than Hass.Pruning to control height and for rejuvenation?

6montholdGEMtreesatCheravo

Ranch

2yearoldGEMtreesatMupu

Ranch

FouryearoldGEMtreesatMupu

Ranch.

0 0 0 0 0 0 03077

0 0 0 0 0 0 0 0 0

12308

0 0

11111 133339426

46880 0 0

13846

125007692

7407

13725

1393418750

10630 8333 5422

17000

14000

13000

15000

1000012500 10000

1300012000

10000

Q04 H01 H02 T01 T02 T03 T04 W01 W02 W03

2013 2014 2015

Lbs/A

GEMAvocado- Mupu RanchAverageYieldperAcre(Lbs./A)

#/Acre14 #/Acre15 #/Acre16 #/Acre17 Projected#/Acre18

9 793 178 299 121 152 410 787 7983,267

7,912

16,051 17,877

37,959

46,000

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

Num

bero

ftreesso

ld

NumberofGEM(3-29-5)treessoldperyearatBNLLC

GEM: world-wide development

Challenges and uncertaintiesCultural• Rootstock effect.• Excessive bloom in young trees can cause leaf drop

(inherited from Gwen).• Cracking of fruit when hanging too late?• We don’t yet have much experience in how it will respond

to pruning. • Growers must take measures to supply the highest quality

possible.

Marketing• Not Hass!!• Inexperience on a commercial scale. First larger

commercial blocks were planted in 2013. • Promotional effort needed to ensure success in the

marketplace.• Packers must take measures to supply the highest quality

possible.

A look into the future…

• Rapid increase in new acreage in the near term.• New GEM blocks going into production àmore fruit entering the market.• From a grower point of view a lot of potential in Gem developmentà Higher efficiencies• To what extent might GEM displace Hass?

GEM Rootstock Trial

Gem/R0.09 Gem/R0.13 Gem/R106 Gem/R.05 Gem/R0.13 Gem/R0.17 Gem/R0.09 Gem/R.05 Gem/R106 Gem/R0.47Gem/R0.09 Gem/R0.13 Gem/R106 Gem/R.05 Gem/R0.13 Gem/R0.17 Gem/R0.09 Gem/R.05 Gem/R106 Gem/R0.47Gem/R0.09 Gem/R0.13 Gem/R106 Gem/R.05 Gem/R0.13 Gem/R0.17 Gem/R0.09 Gem/R.05 Gem/R106 Gem/R0.47Gem/R0.47 Gem/R106 Gem/R.03 Gem/R0.13 Gem/R.05 Gem/R0.30 Gem/R0.17 Gem/R0.47 Gem/R0.18 Gem/R0.13Gem/R0.47 Gem/R106 Gem/R.03 Gem/R0.13 Gem/R.05 Gem/R0.30 Gem/R0.17 Gem/R0.47 Gem/R0.18 Gem/R0.13Gem/R0.47 Gem/R106 Gem/R.03 Gem/R0.13 Gem/R.05 Gem/R0.30 Gem/R0.17 Gem/R0.47 Gem/R0.18 Gem/R0.13Gem/R0.30 Gem/R.05 Gem/R0.06 Gem/R0.15 Gem/R0.18 Gem/R106 Gem/R0.18 Gem/R0.30 Gem/R0.54 Gem/R0.17Gem/R0.30 Gem/R.05 Gem/R0.06 Gem/R0.15 Gem/R0.18 Gem/R106 Gem/R0.18 Gem/R0.30 Gem/R0.54 Gem/R0.17Gem/R0.30 Gem/R.05 Gem/R0.06 Gem/R0.15 Gem/R0.18 Gem/R106 Gem/R0.18 Gem/R0.30 Gem/R0.54 Gem/R0.17Gem/R0.06 Gem/R0.18 Gem/R0.54 Gem/R0.30 Gem/R0.47 Gem/R.03 Gem/R0.13 Gem/R0.54 Gem/R0.09 Gem/R0.30Gem/R0.06 Gem/R0.18 Gem/R0.54 Gem/R0.30 Gem/R0.47 Gem/R.03 Gem/R0.13 Gem/R0.54 Gem/R0.09 Gem/R0.30Gem/R0.06 Gem/R0.18 Gem/R0.54 Gem/R0.30 Gem/R0.47 Gem/R.03 Gem/R0.13 Gem/R0.54 Gem/R0.09 Gem/R0.30Gem/R0.15 Gem/R0.54 Gem/R0.17 Gem/R0.18 Gem/R0.09 Gem/R0.06 Gem/R0.15 Gem/R.03 Gem/R.05 Gem/R0.06Gem/R0.15 Gem/R0.54 Gem/R0.17 Gem/R0.18 Gem/R0.09 Gem/R0.06 Gem/R0.15 Gem/R.03 Gem/R.05 Gem/R0.06Gem/R0.15 Gem/R0.54 Gem/R0.17 Gem/R0.18 Gem/R0.09 Gem/R0.06 Gem/R0.15 Gem/R.03 Gem/R.05 Gem/R0.06Gem/R0.17 Gem/R0.03 Gem/R0.47 Gem/R0.09 Gem/R0.13 Gem/R0.54 Gem/R0.06 Gem/R106 Gem/R.03 Gem/R0.15Gem/R0.17 Gem/R0.03 Gem/R0.47 Gem/R0.09 Gem/R0.13 Gem/R0.54 Gem/R0.06 Gem/R106 Gem/R.03 Gem/R0.15Gem/R0.17 Gem/R0.03 Gem/R0.47 Gem/R0.09 Gem/R0.13 Gem/R0.54 Gem/R0.06 Gem/R106 Gem/R.03 Gem/R0.15

Location:Faught RanchPlantingDate:June2017

Thank you…