Varieties - The recent Queensland experience Chris Searle Technical Advisor Grower Services Suncoast Gold Macadamias

Varieties - The recent Queensland experience Chris Searle Technical Advisor Grower Services Suncoast Gold Macadamias

Successive waves of planting Australia home of macadamias - majority of varieties currently planted originated in Hawaii 1960s - HAES 246, 508 1970, 80s and up to mid 90s - 344, 741, 660 & 246 and 508. NSW dominance of industry Mid to late nineties Australian (A) varieties introduced production started in Bundaberg. 2003-2008 rapid expansion in Bundaberg HAES 816 and 741 dominate plantings 2016 another expansion phase in Bundaberg/ central QLD which varieties will dominate this time?

Why is it important to select right variety? Planting a macadamia orchard is a once in a lifetime experience > 60 year orchard life Critical to get it right no second chances We know there are differences in performance across regions, within regions/within orchards Regional variety trials give regional performance - some problems - Grower experience is important Very brief overview of: What we know? How can you use it? Bundaberg perspective

Typical gently undulating Bundaberg farm Ridges running down through long gentle slopes towards drainage lines and shallow valley bottoms. Height differences only 5-10m.

Highly simplified landscape - sedimentary soils Valley bottom Poorly drained soils perched water tables in summer Possibly sodic subsoils Slope As little as 5-10m Ridge Well drained soils Red earths Red podzolics Hydrosols- saturated for part of year Yellow podzolics Free water

Some varieties do better in some soils than others Mildly sodic subsoil Grow trees above subsoil, big mounds and gypsum program Daddow, 741, 344 Hydrosols Install good drainage, Interception drains Non sodic subsoil high mounds, in-field drains Daddow 344, 741, 842, A203 even 816 does well in dry years Slope A203, HAES 842, 741 (late onset AVG risk in red podzolics) Yellow podzolics Red podzolics Nursery one Ridge A268, A4, A16 A203? AVG risk Red earths

Why you need to match varieties to soil type 741 741 816 816 741 Well drained soils 741 816 741 Poorly drained soils Nursery two 741 816 Nursery one Hydrosol AVG trees removed Abnormal vertical growth (AVG) Yield reduced by half to two thirds Strong variety by soil type interaction 25 years from planting to replanting. At least 100,000 trees need to come out. AVG tolerant varieties need cross pollination

HAES 741 the dominant variety Reasonably high KR 35-39%, Ex quality Yields well (1.5-2t kernel/ha) Clean early/mid season drop Large range nut size small some years Appears to be highly self compatible Not susceptible to husk spot in B berg Tolerates poor soil Good wind tolerance Good tolerance of root diseases, susceptible to Botrospheria Highly susceptible to AVG Needs reasonable drainage/soil mgmt Needs more water good levels of fert Limb removal + hedging? Staying power

HAES 816 rise and fall in 8 years High KR 44-52%, Ex quality Yields well (2t kernel/ha) right conditions Reasonably self compatible Not v sus to husk spot in B berg- sticktights V susceptible to root diseases, tree health Needs excellent drainage/soil mgmt Susceptible to tree loss - strong winds Moderately AVG susceptible Uses less water but needs more fertiliser Suscep to P induced Fe def + more Cu & Zn Probably needs limb removal in long term LOST FAVOUR no longer planted Many don t think it has the staying power? Does it need the right rootstock?

A203 the 816 replacement? Reasonable KR 34-39%, Reasonable quality Yields well (2.3t kernel/ha) right conditions Very precocious (5kg NIS in year 4) Appears to be self compatible? Clean mid/late-mid season drop Small nut (<21mm) very low KR Ok in average soil doesn't like vertisols Reasonable tolerance of root diseases Susceptible to husk spot in B berg Highly susceptible to Botrospheria Needs reasonable drainage/soil mgmt Needs good to high levels of fert AVG status unknown Water requirements unknown Canopy management unknown Looses branches in high winds Staying power?

Rootstocks by soil type? WILL THIS TRANSLATE INTO YIELD? Very early information trial examining performance of HAES 741, 816 and Daddow on H2 (main Australian rootstock) and Beaumont ( main South African) on two soil types - trees growing more vigorously on Beaumont compared with H2 on black cracking clay (vertisol) but similar growth on krasnozem

Summary Planting a macadamia orchard once in a lifetime opportunity vital to get it right Match variety to region and on-farm conditions Don t just consider yield and quality - multiple factors eg soils, disease, pruning, pollination, spacing - now going wider (9x3.5m and 10x3.5m) Use trial data, good observations, consultants Small diffs in yield over 50 years can add up (kg) Make a well thought through farm plan so you get best possible outcomes

Daily water use (L/tree/day) 65 60 55 50 45 40 35 30 25 20 15 max min HAES 741 HAES 344 J A S O N D J F M A M J Time Range in daily transpiration (water use in L/tree/day) for two cultivars 741 and 344, averaged over two seasons (1999/2000 and 2000/2001), growing at Bundaberg under well watered conditions. Water use measured using Grainier sap flow. Trees 6m in height, 312 trees/ha. ( Searle, C, and Lu, P. 2002)