Card Project Progress Report:"Sustainable and profitable development of acacia plantations for sawlog production in Vietnam " MS3 doc

CARD Project Progress Report 032/05VIE Sustainable and profitable development of acacia plantations for sawlog production in Vietnam MS3 Review of Acacia genetic resources and propaga

CARD Project Progress Report

032/05VIE Sustainable and profitable development of acacia plantations for sawlog production in Vietnam

MS3

Review of Acacia genetic resources and

propagation methods to support sawlog

Abstract

Study of the processing of acacia logs in Vietnam’s sawmills indicates that to improve profitability of acacia sawlog production for tree growers, the following essential tree and log criteria need to be improved through a combination of species selection, genetic improvement and silviculture

Survival - high rates of survival are important for stand uniformity and wood yield

Rapid growth - ability to produce a sawlog in the shortest possible rotation (logs as

small as 2 m in length and 15 cm small-end diameter are routinely sawn)

Good stem form – reasonably straight main stem, minimum forking, and light branching

will maximize the proportion of the tree’s production that can be sold as sawlog

Defect-free wood - sawlogs must be free of heart-rot, loose knots and other defects that

cause visible defects in the sawn boards

The history of species and provenance testing and genetic improvement in Vietnam, and the development of selected acacia hybrid clones, is reviewed From this review, the best planting materials for sawlog plantations and the best propagation methods have been

identified Selected clones of the acacia hybrid (A mangium x A auriculiformis) and the best improved planting material of A auriculiformis (selected clones and improved seed) and A mangium (improved seed) are the best suited acacia varieties for sawlog

production, and are already proven in this role in lowland regions of Vietnam receiving at least 1000 mm annual rainfall Details of superior germplasm of these species are

provided in the report A crassicarpa is also promising for sawlog production in these

environments in Vietnam but is not yet proven Improved seed of this species is not yet available Computer software for climate matching is available to display regions of Vietnam which have suitable climates for the growth of these species, and the 3-PG stand

growth model has been parameterized for A mangium in Vietnam

A auriculiformis grows too slowly in northern Vietnam to be considered as a profitable

sawlog-producing species, so acacia hybrid and A mangium are preferred for sawlog production there A mangium is not favoured in the south of Vietnam because its wood quality is seen to be inferior, and production enterprises there prefer to plant A

auriculiformis and acacia hybrid

Although performance of A mearnsii and some provenances of A melanoxylon is

promising in trials at Da Lat, it is too early to recommend acacia species adapted to Vietnam’s highland regions as being suitable for sawlog production Dry-zone acacia species adapted to lowland dry zone environments receiving less than 1000 mm annual rainfall are not suitable for sawlog production because their growth rates are too slow and log quality is too poor

These conclusions have been reached primarily from review of survival and growth data from many trials in Vietnam Less information is available on stem form traits (forking, taper, bark thickness, branch size and stem straightness) of acacias However,

quantitative assessment of stem form traits in clonal trials of acacia hybrid and A

auriculiformis, and some progeny trials of A auriculiformis, shows that these traits are

under moderate to strong genetic control and thus susceptible to genetic improvement, particularly through deployment of selected clones with outstanding stem form Significant improvement in stem form is also achievable through use of improved

seedling stock of A auriculiformis and A mangium

Little information is available on wood properties relating to sawlog production A

auriculiformis has higher wood density than A mangium and is favoured for high-value

appearance products such as fine furniture and flooring One study indicates that acacia

hybrid clones had higher wood density than A auriculiformis at age 5 years Further

information on wood properties is currently being collected by FSIV from clone trials and

progeny trials of A auriculiformis and A mangium, and clone trials of acacia hybrid

clones No quantitative information is yet available on genetic rankings for susceptibility

to pests and diseases such as heart rot and stem cankers that might affect wood quality

When ranking alternative germplasm sources (individual clones and seedlots) for their suitability for sawlog plantations, it is not possible to be precise because the relative economic weights for growth traits, stem form traits and wood properties to maximize plantation and sawmill profitability have not yet been determined The CARD project will formulate economic weights that will enable better rankings of candidate varieties For now, we note that log shape and size, and wood defects, are strongly influenced by silviculture (site selection, initial spacing, thinning and pruning, nutrition management and control of competing vegetation) as well as by species choice and genetic improvement, so silviculture and genetics must be considered together when efforts are made to improve the profitability of sawlog plantations in Vietnam

Table of Contents

Abstract 2

Table of Contents 4

1 Purpose of this review 5

2 Required tree characteristics for acacia sawlog plantations 5

2.1 Experience with processing acacia sawlogs in Vietnam 5

2.2 Overseas experience in growing and using sawlogs of tropical acacia species 8

2.3 Summary of essential tree and log characteristics for acacia sawlog production 10

3 Acacia genetic resources and species-site matching 10

4 Species and provenance testing of Acacia species with sawlog potential 13

4.1 Species-site matching 13

4.2 Species and provenance testing in lowland regions with moderate to high rainfall 13

4.3 Species-provenance trials of temperate Acacia species at Dalat 18

5 Genetic improvement of Acacia species in Vietnam 21

5.1 Establishment of seed production areas and seedling seed orchards of tropical Acacia species for lowland planting regions in Vietnam 21

5.2 Clonal testing and clonal seed orchards of A auriculiformis and A mangium 22

5.3 Development of acacia hybrid clones 25

5.4 Genetic gain trials of acacia species and acacia hybrids 28

6 Summary of recommended acacia species and varieties for sawlog plantations in Vietnam 30

7 Recommended propagation methods 31

8 References 33

1 Purpose of this review

This review has been carried out as Activity 1 of CARD Project 032/05 “Sustainable and profitable development of acacia plantations for sawlog production in Vietnam” It examines the currently available genetic material for acacia sawlog plantations in Vietnam and recommends the best currently available germplasm suitable for sawlog production Appropriate propagation techniques for the recommended germplasm are also reviewed Much information is available from within Vietnam on species and provenance testing, genetic improvement programs, propagation methods and development of acacia hybrid clones for clonal forestry Where this information has already been published, reference is made to these earlier publications, rather than re-presenting the original detail Where local information is lacking in depth, experience from other countries is examined

Recommended strategies for future genetic improvement will be developed as Activity 4.5 of the project, so are not covered here

2 Required tree characteristics for acacia sawlog plantations

First, it is necessary to consider the log quality requirements for acacia sawlog plantations

in Vietnam Use of acacia sawlogs in Vietnam and overseas is considered in this section

2.1 Experience with processing acacia sawlogs in Vietnam

A number of small and medium-sized sawmills sawing acacia logs were inspected in the course of developing the CARD project, and discussions held with sawmill managers The largest sawmill visited was the Huong Giang sawmill and wood processing facility in Hue This plant saws about 2500 m3 of logs per year, mostly acacia, and employs about

300 staff, most of them in downstream processing of furniture based on acacia wood Several smaller sawmills in Ha Tay, Dong Nai, Quang Tri and Quang Binh provinces that use plantation acacia sawlogs were also inspected The sawmills are generally labour-intensive with low-technology hand-controlled log milling systems Sawmill managers have clear understanding of their log requirements Mills such as Huong Giang which have small vertical bandsaws (Figure 2) can saw acacia logs down to a small-end diameter (s.e.d.) of 15 cm under bark Mills with horizontal bandsaws, such as the sawmill of Mr Nguyen Si at Dong Ha, saw logs of at least 20 cm s.e.d., because recovery from smaller logs is too low for profitable operation using this sawing system All the mills studied prefer logs with larger s.e.d (over 20 cm) to achieve higher recovery and productivity

Mills around Hue pay at least 600-800,000 dong m-3 over bark (delivered to mill, volume

calculated from s.e.d and log length) for logs of acacia hybrid and A mangium (small

end diameter under bark down to 15 cm), and rather higher prices for similarly sized logs

of A auriculiformis Some mills pay 1 million dong m-3, at the roadside in the plantation,

for good-quality logs of A auriculiformis and acacia hybrid with s.e.d greater than 20

cm These prices are substantially higher than the prices paid for acacia pulpwood, about 400-500,000 dong per “stere” (= 2 m3 of stacked wood, or about 1.2 m3 solid volume, equivalent to a price of 330-420,000 dong m-3 solid volume) at the roadside adjacent to the plantation at Dong Ha

Most mills concentrate on producing relatively small-sized sawn lumber such as furniture components, seldom exceeding final dimensions of 1000 x 100 x 25 mm Logs are usually cross-cut into lengths of 2 m or shorter, prior to sawing

If larger logs are unavailable, some sawmills with vertical bandsaws will even use logs with a small end diameter of as little as 10 cm under bark to meet production demands, but this reduces recoveries and increases sawing costs Small size of logs (leading to higher cost of milling and lower recovery), and knots, particularly dead knots associated with unpruned stems, causing defects in the sawn wood, are the most important defects in acacia sawlogs under present conditions Sawmills will usually avoid purchasing logs with significant visible defects such as heart-rot or large dead branch stubs

Figure 1 Acacia logs awaiting sawing at Huong Giang sawmill, Hue

Figure 2 Sawing furniture components from small acacia logs using a vertical bandsaw at Huong Giang sawmill, Hue

Figure 3 Sawing trial of acacia hybrid sawlogs at sawmill of Mr Nguyen Si, Dong

Ha, using horizontal bandsaw and rail-mounted log carriage

After sawing, boards are racked and air-dried for 2-3 weeks, which is sufficient time for the small piece sizes typically produced Larger boards up to 40 mm thick may be dried for longer periods, sometimes in kilns, and then re-sawn Mills report few problems of

drying degrade with acacia hybrid and A auriculiformis, but some problems (cupping, excessive shrinkage, unacceptably low wood density and checking) with A mangium,

particularly in the south of Vietnam

Wood of A auriculiformis, acacia hybrid and sound wood of A mangium is acceptable

for manufacture of mass-produced furniture (such as component pieces for indoor and outdoor furniture) for local and export use It appears acceptable for these components to have a mix of sapwood and heartwood, despite the strong sapwood-heartwood colour difference in acacia wood Furniture is typically stained or painted in the final assembly process

Acacia auriculiformis wood is regarded by the sawmillers as denser and harder than the

wood of acacia hybrid and A mangium, and is considered to have more attractive colour and grain The higher wood density of A auriculiformis compared to A mangium of the

same age is confirmed by empirical studies in Vietnam (Le Dinh Kha 2001) and

elsewhere (CAB 2003) Large A auriculiformis logs are especially favoured by sawmills,

because large boards of this species can be used for high-value “appearance” applications

including flooring and fine furniture It is not yet clear whether and to what extent A

mangium and acacia hybrid can substitute for A auriculiformis in these higher-value

applications

Small quantities of Acacia crassicarpa logs are now available from the first plantations of

this species in Vietnam, but sawmills are not yet familiar with this species Experience in

Australia and other countries is that A crassicarpa can produce good-quality sawn timber

(Doran and Turnbull 1997)

All sawmills visited to date confirmed that they would take more acacia sawlog timber from local growers, if it was available at the prices they currently pay During 2004-2005,

large sawmills around Ho Chi Minh City imported A mangium sawlogs from Malaysia

for processing The log specifications required by these sawmills have not yet been

studied, and no firms importing A mangium logs could be located in 2006

2.2 Overseas experience in growing and using sawlogs of tropical acacia species

Growing of tropical acacia species specifically for solid-wood uses is expanding rapidly

in several other countries in South East Asia, most noticeably in Indonesia and Malaysia

(Midgley and Beadle 2006, S.J Midgley pers comm 2006) A mangium is the most

important acacia species in these two countries To date, silvicultural inputs into acacia plantations managed for solid wood have seldom included pruning and thinning, though

the potential of these practices for a species like A mangium has been recognised for

some time (Srivastava 1993) Persistent branches have led to the development of pruning regimes with the intention of converting the bottom log to clear or knot-free wood Form pruning that removes large branches and branches forming an acute angle with the stem has been shown to significantly improve stem form (Beadle 2006) As the plantations are established at around 1000 stems ha–1, thinning is also required to develop large log diameters (Figure 4) In Indonesia, it is anticipated that final-crop stocking will

lift-be around 300 stems ha–1 for crops being harvested when tree dbhob is 30 cm (Beadle

2006) Heart-rot and root-rot are significant problems for A mangium plantations in Indonesia (Potter et al 2006)

Sumatra Average dbhob and height and total stem volume were 36.6 cm, 26 m and 228.7 m ha respectively (after Hardyanto 2006) 3 –1

Malaysia, which has a long history of planting A mangium (Pinyopusarerk 1993) is a major exporter of A mangium wood Several companies actively export both logs and

sawn timber that has been processed to a greater or lesser extent For example, log prices

in 2005were around $US 50 m–3 and finger-jointed timber $US 900 m–3 FOB (Midgley

and Beadle 2006) In 2003, Vietnamese furniture manufacturers were importing A

mangium sawlogs from Malaysia at a landed price of up to $US 85 m-3.

A considerable body of published information is available on the properties processing

characteristics of A mangium wood (Abdul-Kader and Sahri 1993, CAB 2003, Hardiyanto 2006, Kumar et al 2006) In summary, the wood is of medium density

(typically 420-480 kg m-3) and is relatively easy to dry and saw, and process into finished furniture components Shrinkage is moderate (typically about 6% tangential and 3% radial shrinkage from green to air dry), and the wood can be cut, sanded, glued, stained and painted easily “Acacia” furniture, manufactured from the wood of tropical acacia

species, mainly A mangium, is now a recognized international product type marketed by

global companies such as IKEA

2.3 Summary of essential tree and log characteristics for acacia sawlog production

In summary, acacia wood from at least A auriculiformis, acacia hybrid and A mangium

can be used by Vietnam’s sawmills to produce sawn boards for furniture components Individual sawlogs purchased are generally at least 2 m in length, with small end diameter under bark of at least 15 cm, reasonably straight and without obvious defects such as heart rot, cracks and loose knots When plantations are harvested, small and crooked trees and upper logs which do not meet these specifications are usually sold separately to pulpwood and fuelwood markets Using the best genetic resources and optimizing silviculture will enable growers to maximize the proportion of log volume which can be sold, at higher price, as sawlogs

It follows that for acacia sawlog plantations, the following essential tree and log criteria need to be improved through a combination of genetic selection and silviculture:

Survival - high rates of survival are important for stand uniformity and wood yield

Rapid growth - ability to produce a sawlog in the shortest possible rotation

Good stem form – reasonably straight main stem, minimum forking, and light branching

will maximise the proportion of the tree’s production that can be sold as sawlog

Defect-free wood - sawlogs must be free of heart-rot, loose knots and other defects that

would cause visible defects in sawn boards and lead to them being rejected for further processing

3 Acacia genetic resources and species-site matching

Acacia species have become important plantation species in Vietnam over the last two

decades They display rapid growth even on degraded soils, and form symbiotic associations with nitrogen-fixing bacteria, thus reducing the requirement for fertilizer

inputs Acacia wood can be used for both pulpwood and sawn timber In Vietnam, there are about 15 native Acacia species (Nguyen Tien Ban et al., 2003), but these are small and shrubby and of no economic value for wood production in plantations The Acacia

species now planted in Vietnam are native to Australia and in some cases the adjacent regions of Papua New Guinea (PNG) and West Papua, Indonesia (Nguyen Hoang Nghia

and Le Dinh Kha, 1998) There are many hundreds of Acacia species occurring in

Australia and adjacent countries The identification of suitable candidate species, collection of genetic resources of these species and their introduction to Vietnam has not occurred in isolation, but as part of an international testing program supported by the

Australian Government, FAO and CSIRO that has operated since the 1970s (Turnbull et

al 1998)

Climates vary greatly within Vietnam The wide range of altitude and latitude, and the effects of mountain ranges on monsoon systems, result in substantial differences in

rainfall and temperature regimes As a result the Acacia species planted in Vietnam can

be considered in three groups:

Species adapted to tropical lowland environments with medium to high rainfall

The best-performing of these species are A auriculiformis, A crassicarpa and A

mangium, which are all native to northern Queensland (Qld), Australia and adjacent PNG

and West Papua, Indonesia A auriculiformis also occurs naturally in Australia’s Northern Territory (NT) A auriculiformis, A mangium and selected clones of the interspecific hybrid A mangium x A auriculiformis are the most widely planted acacia

species in Vietnam (Nghia and Kha 1998, Centre for International Economics 2004)

Species suited to low-rainfall tropical lowland environments

Coastal areas of Binh Thuan and Ninh Thuan provinces in the south of the country in have a dry climate, receiving mean annual rainfalls lower than 1000 mm per year Sandy

soils are prevalent in flat terrain near the sea coast In the 1980s it was found that A

auriculiformis and A mangium perform poorly in these environments, being prone to

drought death in dry years Dry-zone acacias from northern Australia were tested at Tuy Phong in Binh Thuan Province in the 1990s (Harwood et al 1998) The best-performing

species were A difficilis, A tumida and A torulosa Subsequently, A difficilis was also

found to have a valuable role in establishing vegetation cover on extremely eroded shallow soils of bare hills in central and northern Vietnam, and the dry-zone species were also planted for stabilizing moving coastal sands in other provinces with higher rainfall such as Quang Binh province However, none of these dry-zone species attain maximum heights greater than 10-12 m, and they fork and branch heavily from a low height, so they cannot produce straight sawlogs Their growth rates in low-rainfall environments are slow In the species trial at Tuy Phong mean maximum height at age 6 years was only 7.5

m and mean maximum diameter at breast height 15 cm for A difficilis, the growing of these species In wetter lowland environments they are out-performed by A

fastest-auriculiformis, A crassicarpa and A mangium This makes them unsuited for sawlog

production, and they are not considered further in this review

Species suited to highland environments in Vietnam

There are large areas of land in the north and centre of Vietnam where elevation exceeds

1000 m and the climate is cooler than optimum for the tropical acacias, with mean annual temperature below 21oC (Nghia 1996) Species and provenance trials were carried out in the 1990s to identify the best-performing temperate acacias for these cooler

environments A mearnsii and A melanoxylon have been found to be the best performing

species in highland Vietnam, which is consistent with their good performance in tropical

highland regions in other countries A mearnsii is now widely used for planting in tropical highland areas in India, China, South America and Africa (CAB 2003) A

melanoxylon is a favoured species for production of sawn timber from natural forests in

its native range in Australia (CAB 2003, Doran and Turnbull 1997)

Climatic requirements of the most important candidate species for sawlog production are

summarized in Table 1 below A climatic mapping program was produced by Dr T.H

Booth of CSIRO Forestry and Forest Products which enables display of areas in Vietnam

satisfying any set of climatic requirements such as those shown in Table 1 This software

has been used by the Forest Science Institute of Vietnam (Nghia, 1996) to display areas

climatically suitable for planting of A auriculiformis and A mangium

Table 1 Climatic requirements for most important candidate Acacia species

for sawlog production in Vietnam

Acacia species suited to lowlands of Vietnam Acacia species suited to highlands

Climatic factor auriculiformis1 crassicarpa2 mangium1 mearnsii3 melanoxylon4

modified fromNghia (1996) In northern Vietnam A mangium can tolerate slightly lower

winter temperatures than can A auriculiformis It can be grown at elevations up to about

300 m in the northernmost provinces of Vietnam, whereas A auriculiformis can only be

grown at elevations up to 100 m there The climatic range for acacia hybrid clones is

probably intermediate between those of A auriculiformis and A mangium

natural provenances of A melanoxylon occur over wide geographic range from Tasmania

to Queensland, so climatic requirements of specific provenances will differ

Subsequently, with funding support from the International Greenhouse Partnerships

Program of the Australian Government, the 3-PG process-based forest growth model was

calibrated for A mangium in Vietnam, enabling growth and carbon sequestration of A

mangium to be predicted at example locations in different regions across Vietnam, taking

into account climate and local soil conditions (Booth et al 2001)

4 Species and provenance testing of Acacia species with

sawlog potential

4.1 Species-site matching

In the early 1960s, A auriculiformis was introduced for planting in south-eastern

Vietnam From the 1980s, systematic trials of this and other Acacia species known to

have good potential for industrial plantations were carried out by the Forest Science

Institute of Vietnam and other research agencies, usually in collaboration with Australia’s

CSIRO, which supplied most of the seedlots under test Species-provenance and

provenance trials have been carried out at many locations across Vietnam The locations

of trials reviewed here are summarized in Table 2, below Most of the results obtained to

2003 are summarized by Le Dinh Kha (2003)

Table 2 Site details of Acacia species-provenance and provenance trials in Vietnam

Altitude (m)

Mean annual rainfall (mm)

Soil type

Da Chong Ha Tay 21o07 105o26 60 1680 yellow-red ferralitic soil

over 50 cm deep developed over sandstone Cam Quy Ha Tay 21o07 105o26 60 1680 yellow-red ferralitic soil

over 50 cm deep developed over sandstone Dai Lai Vinh Phuc 21o10 105o17 50 1500

Dong Ha Quang Tri 16o50 107o05 2370 ferralitic soil developed

over schist

Mangyang Gia Lai 13o59 108o10 800 2270 granite-derived soil Song May Dong Nai 11o05' 107o06 50 1640 grey soil developed from

alluvial deposits Bau Bang Binh

Duong

11o32 105o56 50 grey soil developed from

alluvial deposits

Da Lat Lam Dong 11o57 108o26 1600 1730 yellow-red ferralitic soil

on magma acid rock, pH 4.5-5.0

4.2 Species and provenance testing in lowland regions with moderate

to high rainfall

Species-provenance trials

In the 1980s, A auriculiformis, A mangium, A crassicarpa and A aulacocarpa were

introduced to establish pilot plantations at Ba Vi (Ha Tay province), Hoa Thuong (Thai

Nguyen province) and Trang Bom (Dong Nai province) Assessment in 1991 of pilot

plantations established at Ba Vi in 1982 and at Hoa Thuong in 1984 showed that the most

promising species were A auriculiformis, A mangium and A crassicarpa A

auriculiformis displayed the fastest early growth (Le Dinh Kha and Nguyen Hoang

Nghia, 1991)

From 1990 to 1991, under projects financed by UNDP, trials of 39 provenances of 5 tropical acacia species were established at Da Chong (Ba Vi, Ha Tay province, northern Vietnam), Dong Ha (Quang Tri province, central Vietnam) and Dai Lai (Vinh Phuc province, northern Vietnam)

The species/provenance trials established in 1990 at Da Chong and Dong Ha included 13

provenances of A auriculiformis, 9 provenances of A mangium, 9 provenances of A

crassicarpa, 5 provenances of A aulacocarpa and 5 provenances of A cincinnata,

provided by CSIRO All provenances came from Queensland (Qld) and Northern Territory (NT) of Australia; Papua New Guinea (PNG) and Indonesia (Ind) Local

seedlots of A auriculiformis and A mangium from Dong Nai of A were used as controls

The trial at Da Chong used a randomized complete block design with 3 replications and

49 trees per plot The trial in Dong Ha was established in 1991 This trial had only one replication with 49 trees per plot The trial at Dai Lai (Vinh Phuc) included all 13

provenances of A auriculiformis

The trial at Da Chong was measured in 1999 at age 9 years after planting at Da Chong Mean total stem volumes over bark of each species, in dm3/tree, (assuming a standard stem form factor of 0.5) were as follows:

Log volumes are only approximate, being strongly influenced by stocking, which in turn

is influenced by survival, so the mean volumes shown above should only be taken as an indication Nonetheless, this result demonstrates the substantial log size that can be attained by the tropical acacias in nine years on a reasonably productive site in northern Vietnam

Another species/provenance trial of A mangium, A auriculiformis, A crassicarpa, A

aulacocarpa and A cincinnata was established by Phu Ninh Forestry Research Centre in

in 1992 on granite-derived soil at Mangyang, Gia Lai province, central Vietnam (Mai

Dinh Hong et al 1996) After 4 years A crassicarpa, A mangium and A auriculiformis

were the best-performing species Bloomfield (Qld) and Pongaki (PNG) provenances of

A mangium, Coen River (Qld) and Kings Plain (Qld) provenances of A auriculiformis

and some provenances of A crassicarpa were the fastest growing and A cincinnata was

the poorest species These conclusions on promising species and provenances generally agreed with other results (Le Dinh Kha 2003)

Generally, in the trials of tropical acacia species, A crassicarpa, A mangium and A

auriculiformis have performed best A aulacocarpa and A cincinnata are slower

growing species and hold little promise for plantation forestry in Vietnam (Le Dinh Kha

2003) The taxonomy of A aulacocarpa is complex: the best-performing provenances of

this species, which occur naturally in Western Province, PNG and adjacent West Papua,

Indonesia, have been renamed A peregrinalis (McDonald 2000)

Evaluation of the species-provenance trials established at Ba Vi, Dong Ha and Dai Lai showed that after 912 years the best-performing tested provenances in northern and central Vietnam were:

A auriculiformis: Mibini (PNG), Coen River and Kings Plains (Qld) and Manton River

(NT)

A mangium: Pongaki (PNG), Iron Range (Qld), Ingham (Qld) and Mossman (Qld)

A crassicarpa: Mata (PNG), Gubam (PNG), Dimisisi (PNG) and Deri-Deri (PNG)

A auriculiformis provenance trials

In 1990, a provenance trial of A auriculiformis was established at Dai Lai Nine years

after planting, Coen River (Qld) was the best provenance of those tested in this trial Data collected at Ba Vi and Dai Lai at age 12 years (Table 3) showed that Mibini (PNG), Coen River (Qld) and Kings Plains (Qld) were promising provenances at both sites, while Manton River (NT) was fast growing at Ba Vi but mid-ranked at Dai Lai

A series of provenance trials of A auriculiformis was established in Cam Quy (Ha Tay),

Dong Ha (Quang Tri) and Song May (Dong Nai) under the ACIAR project 9310 A local seedlot from Dong Nai was included in these trials as a control In the trial in Song May

at 5 years the best-performing provenances were Wenlock R (Qld), Halroyed (Qld) and Morehead (PNG), while at Cam Quy the best provenances were Halroyed (Qld) and Rifle

Creek (Qld) In these three trials the Dong Nai local race of A auriculiformis displayed

intermediate to slow performance The fastest growing provenances had volumes two times greater than those of the slowest

At Song May the mean stem volume of 16 provenances at age 5 years was 90.0 dm3 per tree, while at Dong Ha it was 30.1 dm3, and at Ba Vi only 20.4 dm3 All trials used the same spacing of 3m x 2m This result shows that differences in climatic and soil

conditions in Vietnam have a major impact on the growth of A auriculiformis

Table 3 Growth of A auriculiformis provenances at Dai Lai and Ba Vi

Height (m)

Dbh (cm)

A mangium provenance trials

In 1989 - 1990, provenance trials of A mangium were established at Bau Bang and Song

May by the south-eastern Forest Science and Production Centre At age 8.5 years, there were substantial differences in growth between the two sites (Table 4) Waterlogging at Bau Bang appeared to be the cause of the slower growth there

Only one provenance from PNG, Deri-Deri, was tested This proved fastest-growing at both sites The Olive River and Pascoe River from the Far North Queensland region of Queensland also performed well when tested at Song May This is consistent with results

in other countries (Harwood and Williams 1992) Earlier Vietnamese provenance trials

of A mangium did not test the PNG provenances of the species, so it is difficult to draw

useful conclusions from them

Table 4 Growth of provenances of A mangium in Bau Bang and Song May

Bau Bang (to 10.5 years)

Song May 1 (to 10.5 years

Song May 2 (to 9.5 years) Seedlot Provenance

Height (m)

Dbh (cm)

Height (m)

Dbh (cm)

Height (m)

Dbh (cm)

A crassicarpa provenance trials

In September 1991, a provenance trial of A crassicarpa was established at Bau Bang,

where the site conditions are similar to those at Song May After 8.5 years, the

best-performing provenances of A crassicarpa at Bau Bang were Dimisisi, Deri -Deri,

Morehead and Bensbach, all from PNG (Table 5) The slowest-growing provenances

were those from Indonesia and Queensland A crassicarpa clearly out-performed a local seedlot of A auriculiformis in this trial

Table 5 Growth of A crassicarpa provenances at Bau Bang (1991-1999)

A crassicarpa has been observed to outperform other acacia species on the coastal white

sandy soils of central Vietnam, for example in Thua Thien Hue Province These soils are low in fertility and subject to seasonal waterlogging There are many thousands of hectares of these low-lying white sandy soils in coastal regions of central Vietnam, and

the area of A crassicarpa plantations in these environments is expected to expand

rapidly However, producing logs of sufficient size for sawing and achieving

sustainability of production will be particularly challenging on these difficult, infertile sites

Identification of superior acacia provenances by MARD

On the basis of species and provenance trials conducted in Vietnam, in 2000 the Ministry

of Agriculture and Rural Development issued Decision No 4260/KHCN-NNTT to

approve the following provenances as Technological Advanced Germplasms for mass

planting in suitable ecological zones:

A auriculiformis: Coen River (Qld), Morehead River (Qld) and Mibini (PNG)

A crassicarpa: Mata province (PNG), Deri-Deri (PNG) and Dimisisi (PNG)

A mangium: Iron Range (Qld), Cardwell (Qld) and Pongaki (PNG)

Results from other tropical countries support the superior ranking of most of these

provenances, with the exception of the Cardwell provenance of A mangium Provenance and progeny trials of A mangium in many countries including Australia, China, Indonesia

and Malaysia (Harwood and Williams 1992), and the Philippines (Arnold and Cuevas 2003) have confirmed that Cardwell is not a fast-growing provenance of this species, when compared with most provenances from PNG, and provenances from the Far North Queensland region (Claudie River/Iron Range, Olive River and Pascoe River) We

recommend that Cardwell should no longer be classed as a superior provenance of A

mangium It is also noted that there are other provenances of A auriculiformis, A crassicarpa and A mangium not tested in provenance trials in Vietnam which have

performed equally well as those identified by MARD Some of these provenances are represented in the seedlings seed orchards and seed production areas subsequently established by FSIV

4.3 Species-provenance trials of temperate Acacia species at Dalat

In 1996, through a project sponsored by ACIAR and in cooperation with CSIRO, the Research Centre for Forest Tree Improvement (RCFTI) established a series of species/provenance trials of temperate acacias at several highland sites, including Da Lat (altitude 1600m), Tam Dao (1000m), Moc Chau (1000m) and Ba Vi (600m)

Preliminary assessments conducted in 1997 showed that survival and growth of these

species was best at Da Lat (Ha Huy Thinh et al., 1998), therefore evaluation in later ages

focused on the trial at Da Lat (Table 6)

Da Lat has a mean annual temperature 18.3oC, a mean maximum of the hottest month of 23.3oC, and a mean minimum of the coldest month of 14.3oC The absolute minimum temperature is -0.1oC (recorded in January 1932) Mean annual rainfall is 1730 mm/year, and the rainy season is mostly from April to October, peaking in September - October (Nguyen Trong Hieu, 1990)