Macadamia Nuts in Hawaii: History and Production - ctahr ...

Figure 45. Windbreaks in macadamia nut fields: Syncarpia laurifolia on the left and A raucaria excelsa on the right.
Naquin planted predominantly the integrifolia
at Honokaa, presumably because the Purvis integrifolia
trees planted nearby were the major seed
source. Van Tassel did the same for his orchard at
Nutridge. Unfortunately, some of the trees planted
in Keauhou, Kona, before Moltzau's time and used
as intercrop and shade sources in the coffee fields
were tetraphyllas. Moltzau remembers demonstrating
the tree topworking technique to Kona
farmers by actually topworking hundreds of trees
beginning in 1928. Fortunately, he also persuaded
the Kona farmers to plant integrifolias.
All five cultivars named by Storey by that time
were extensively planted at Keaau Orchard,
beginning in 1949. Only two of these, 'Keauhou'
and 'Kakea', however, showed good commercial
possibilities by 1953. The other cultivars were
topworked with 'Keauhou', 'Kakea', anda recently
named cultivar, 'Ikaika'.
In 1952 Hamilton and Fukunaga named 'Ikaika'
(HAES 333) and 'Wailua' (HAES 475), of which
only 'Ikaika' is now cultivated commercially. In
1966 Hamilton and Ooka (17), introduced 'Keaau'
(HAES 660), and in 1971 Hamilton and Nakamura
(18) introduced 'Ka'u' (HAES 344). Hamilton and
Ito (19) named 'Mauka' (HAES 741) and 'Makai'
(HAES 800) in 1977, implying that cultivar
'Mauka' is for the higher elevations above 1800
feet and cultivar 'Makai' is suited to elevations
below 1600 feet. In a paper presented at the 1981
36
annual meeting of the Macadamia Producers
Association, Hamilton (20) named two new cultivars,
'Purvis' (HAES 294) and 'Pahala' (HAES
788).
As of this date, 13 M. integrifolia cultivars in
Hawaii have been assigned names. The older
orchards are predominantly planted to 'Keauhou',
'Kakea', and 'Ikaika', the cultivars then available.
The more consistent cultivar recommendation
currently given by most farmers is to plant 'Kakea',
'Ka'u', and 'Keaau'. The nut size of 'Keaau' is
somewhat small, but it is a good yielder of both inshell
nuts and quality kernels. It is also a thinnershelled
nut and possibly can be recommended as a
seed source. It is also a more confined tree and is,
therefore, more economical in terms of space.
'Ka'u', a relatively new variety, is also a confined,
upright tree that seems to be more wind tolerant
and yields heavily.
Clonal Tree Propagation
Rootstock. The structural formation of the
roots on the rootstocks used in grafting macadamia
nut trees is one of the most important
aspects in tree production. Root structural
evidence collected in the last 20 years seems to
indicate that the method now employed could be
modified to lessen the expensive and eventual loss
of trees in a developing orchard.