(F): PD 528/08 Rev.1 (F): Towards Sustainable Indigenous Mahogany

PD 528/08 Rev.1 (F):

PD 528/08 Rev.1 (F): Towards sustainable indigenous Mahogany production in Ghana: Phase II, refining the silviculture “tool kit” and practical training for industrial-foresters and community farmers

The effects of rooting media on vegetative propagation of two mahogany species (Khaya ivorensis and Khaya grandifoliola)

Opoku, E. M.2, Opuni-Frimpong, E.1 and Adomako, A. A.2 1) Forestry Research Institute of Ghana 2) Kwame Nkrumah University of Science and Technology

SUMMARY

The establishment of plantations with resistant clones can help meet future demand for the mahogany wood as the available stocks in the natural forest stock has declined. The success of the vegetative propagation method in producing resistant progenies for plantation establishment of Khaya grandifoliola and Khaya ivorensis have been accentuated which paves way for commercial utilization of the method. The use of a very suitable rooting medium to promote rapid rooting and subsequent growth of the Mahogany species maintains the genetic integrity of the species for regeneration. This study assessed the effects of rooting media: river sand, loamy soil and mixtures of river sand and loam (50:50 v/v) on the rooting of Khaya grandifoliola and Khaya ivorensis. The rooting media ability to influence rooting was depicted in the highest root formation (5.92), with root length 8.72cm and Survival percentage of cuttings (71%) in the 50:50v/v mixtures of river sand and loam for Khaya grandifoliola which differed slightly from the other media. Khaya ivorensis also exhibited its highest root formation (4.16) in loamy soil with highest root elongation 8.58cm in river sand media and lastly highest survival of cuttings in the loamy soil at 61%. Hence a 50:50 v/v mixture of river sand and loam is best for Khaya grandifoliola regarding root formation, elongation as well as Survival of cuttings. However, loamy soil is suitable for numerous root formation and good Survival in Khaya ivorensis whiles river sand is suitable for numerous root elongation. The study gives a model indication that vegetative propagation of the two Mahogany species can help intensify the restoration of mahogany resource using the suitable rooting medium for the production of resistant progenies to the shoot borer in plantations. The study can also help in meeting future seedling demands.

1.0. Introduction 1.1 Background of the study African Mahoganies have gained local and international recognition among the most marketable tropical timber species (Atuahene, 2001). African mahogany comprises species of the genus Khaya, Entandrophragma, Lovoa and Guarea from the family Meliaceae (Styles, 1975; Lamb, 1996; Opuni- Frimpong et al., 2008). They are widely found in Cote d’Ivoire, Cameroon, Guinea and Uganda and are common in Ghana (Lemmens, 2008; Opuni-Frimpong, 2008). Khaya ivorensis and K. grandifoliola are among the most valued and highly prized Mahogany species in Ghana (Oteng-Amoako, 2006). The attractive feature of the Mahogany wood as well as its pinkish brown to pale red colour and the easiness to cut, taking a smooth surface after polishing, all make the wood very suitable for furniture and carpentry (Irvine 1961; Lemmens, 2008). Also, they are desired for light construction, flooring, carving, ship building, handles, ladder and pulp wood. Moreover, the bark decoctions are widely utilized in traditional medicine for the treatment of cough, fever, anaemia and also applied externally to wounds and sores (Abbiw, 1990). In Nigeria, they are retained in cocoa plantations for timber production and shade whiles in Uganda they are used for stabilization of riverbanks (Opuni-Frimpong, 2008). Due to these desirable features and versatile uses, its popularity in export has increased over the years (FAO, 1993; Atuahene, 2001). For instance in the 1950’s, Ghana exported about 100,000m3 of Mahogany wood forming approximately 70% of the total annual export. Exportation of Mahogany continues to be a source of revenue in Ghana although reduction in volumes of export has occurred considerably due to decreasing stocks in the natural forest. The revenue generation despite its decline is evident in exportation of about 17000m3 of Mahogany wood from Ghana in 2005 (Opuni- Frimpong, 2008). This notwithstanding, demand for its wood keeps rising and thus requires techniques of sustaining the resource to meet its current and future supply whiles maintaining the integrity of the resource. Consequently, plantation establishment of Mahogany by producing genetically resistant progenies through vegetative propagation would enhance regeneration of depleted stocks of the resource. Vegetative propagation offers an affordable method of raising genetically tolerant Mahogany clones to the shoot borer (Hypsipyla robusta) as it has been the main destructive pest which hinders the establishment of Mahogany plantations. Production of genetically tolerant progenies would facilitate renewal of Mahogany resource in order to enhance sustainable supplies in the global market. 1.2 The Problem Statement Owing to continuous exploitation of the Mahogany timber, decline of the resource has occurred prompting the International Union for Conservation of Nature to classify most of the species as vulnerable in the Convention on International Trade in Endangered species (CITES) red list (IUCN, 2004). This decline status of the resource led conservation managers to devise means of regenerating the resource that would ensure sustainable supplies (Taylor, 1960). Efforts to restore Mahogany stock in the natural forest through natural regeneration mostly produced limited successes since viability of the seeds were lost in a short period and seedling predation was very high under natural conditions (Wilson, 1988; Swaine et al., 1996).

According to Gullison et al., (1996) and Snook, (2003) an alternative approach to natural regeneration was to establish plantations that would enhance re-establishment of the depleted resource base. However, the establishment of plantations was threatened by the continuous attack by the Mahogany shoot borer; Hypsipyla robusta (Moore), Lepidoptera: Pyralidae (Opuni- Frimpong et al, 2008; Newton et. al.1993; Wagner et al, 1991). The Hypsipyla robusta larva bores into and feed in the succulent part of the apical dominant shoots of the young tree (Robert, 1968; Newton et al., 1993; Griffiths, 2001).This result in excessive branching, poor quality timber production, and subsequent death of infested trees in some cases (Wagner et al., 1991; Newton et al., 1993; Griffiths, 2001). This has led to the total abandonment of some Mahogany plantations by foresters, farmers and other plantation developers (Apetorgbor and Bosu, 2006). 1.3 Justification Several methods have been suggested to control Hypsipyla robusta in plantations such as mixed planting with resistant species, removal of lateral shoots, biological and chemical control (Newton et al., 1993; Mayhew and Newton, 1998; Opuni- Frimpong et al, 2008). Nevertheless, none of the methods have reduced the shoot borer attack to economically acceptable level in isolation (Wagner et al., 1991). Studies have shown that, it is probably impossible to completely eliminate the shoot borer attack (Newton et al., 1993), but the use of integrated pest management approach can reduce its occurrence to economically tolerable level (Floyd et al., 2000; Newton et al, 1993; Mayhew and Newton, 1998). As part of the approaches to reduce the incidence Hypsipyla robusta attack, there is an advocacy of establishing genetically resistant species to the Hypsipyla robusta in plantations (Newton, 1993; Mayhew and Newton, 1998). Thus, there are efforts to identify resistant planting materials from range wide provenance selection from the isolated trees left in the fragmented forest landscapes in Ghana. The best means to retain resistant character of planting materials is through vegetative propagation (Schwabe, 1971; Tchoundjeu, 1989). According to Hartmann (1990) and Ofori-Gyamfi (1998) the rooting medium used for propagation plays a major role influencing rooting of cuttings in the vegetative system. Different rooting media have been investigated to account for higher rooting in vegetative propagation methods on some timber species (Tchoundjeu et.al., 2002; Ofori et al., 1996). Unfortunately, studies on the appropriate rooting medium to optimize vegetative propagation of Mahogany trees are limited which might affect the rooting efficiency of the method in bulk propagation if not considered and explored (Mayhew and Newton, 1998). Hence, to realize the full potential of vegetative propagation system in production of progenies resistant to the shoot borer in plantations, there is the need to research into a most suitable rooting medium for Mahogany species as its influences on rooting varies among species (Leakey et al., 1990; Ofori-Gyamfi, 1998). 1.4 Research Objectives The research objective for this study was to: 1. Assess the rooting response of Khaya grandifoliola and Khaya ivorensis in the following rooting media: (i) river sand, (ii) loamy soil and (iii) 50:50 v/v mixtures of river sand and loam (Mixed medium).

2. To find out the most suitable medium rooting medium to enhance vegetative propagation of the two species in commercial scale. 3. Find out the survival rate of cuttings of the two species in each of the three media.

1.6 Research Questions With the view of addressing the research objectives the research questions of this study were as follows: 1. Which rooting medium recorded the greatest number of roots of the two Mahoganies; Khaya grandifoliola and K. ivorensis? 2. Which rooting medium promoted rapid root elongation for the two species? 3. Which species showed highest cuttings thriving in each of the rooting media?

2.0 MATERIALS AND METHODS

2.1 Study site The study was conducted at the Council for Scientific and Industrial Research, Forest Research Institute of Ghana (CSIR-FORIG) trial site at Fumesua. FORIG is located at Fumesua 15 km from Kumasi, on the Accra-Kumasi high way with geographically location at 6°44´N, 1°30´W; and relief 280 m above sea level. It lies in the moist semi-deciduous forest types of Ghana’s tropical forest with an annual precipitation ranging between 1200-1750mm per annum (Hall and Swaine 1981). There is a dry season between December and March with rainfall not less than 100 mm per month.

2.2 Propagation Setup and Stem Cuttings preparation The media for the trial were river sand collected from streamside, loamy soil and 50: 50v/v mixture of the two media thus river sand and loam. The rooting media were prepared by pasteurization (Scalabrelli et al., 1983). They were pasteurized when moist for 30min by heating over an open cast metal plate and cooled (Kester, 1990; Larsen and Guse, 1997). The different rooting media were spread in the non mist propagators over a layer of stone gravel placed on an impervious polythene sheet base, watered and then covered with a 0.5 mm thick white polythene sheet (Jeruto et al., 2008). Stem cuttings of the two mahogany species Khaya grandifoliola and Khaya ivorensis harvested from actively growing shoots were dissected into single-node cuttings approximately to length of 6cm. Stem cuttings were collected only in the morning hours, and were kept at a cool place to maintain a humid atmosphere (Agbo and Obi, 2007). Secateurs were used to size the bases of all the cuttings squarely to avoid one-sided rooting and the cut bases were immersed in water up to a length of 1 cm to avoid water loss and thereby prevent wilting. Each of the stem cuttings was stuck in different rooting media at an approximate depth of 2.5 cm (Kester et al., 1990). The rooting media were then compacted around the bases of the cuttings to provide support and watering was carried out every day to moisten the media. The temperature and humidity in the propagators was kept at 28-30°C and 70-80% respectively (Cheesman and Spencer, 1936; Hartmann and Kester, 1997). Monitoring was carried out every day to detect dead leaves and cuttings.

2.3 Experimental Design In the experiment, twenty four (24) cuttings for each treatment were replicated three times were arranged in a completely randomized design. The propagators were filled with equal volumes of the treatment and stem cutting of each species were distributed equally.

2.4 Data Collection Data were collected on the parameters such as number of roots per cuttings and length of longest roots per cuttings for the two species. Numbers of roots were taken by direct counting whiles root length was measured with a ruler. Total number of roots emerging per species in each medium were counted and recorded. Number of cuttings thriving in each medium was recorded. Dead cuttings observation was made for each treatment. 2.5 Data Analysis The data was imputed into the graphical tools of Excel 2007. Mean number of roots and standard errors were computed for each species and presented in simple graphs. Data were subjected to Analysis of variance (ANOVA) at (p < 0.05) to test significance differences between the three media of the parameters measured and where differences between treatments were significant (LSD) Least square difference were used to compare the impact of the different rooting media.

3.0 RESULTS 3.1 Root formation of Khaya grandifoliola The highest mean number of roots for Khaya grandifoliola per cuttings 5.92 was obtained for cuttings rooted in the 50:50 v/v mixtures of river sand and loam (mixed medium), followed by river sand (3.07) and the lowest root formation was observed in loamy soil at a value 3.02 as shown in fig.1. There was a difference between the media for the number of cuttings rooted at p < 0.05 but not very significant. This result is related to Newton et al., (1993), in an initial phase of Swietinia macrophylla in non-mist propagators where highest rooting of cuttings was obtained in a rooting medium with high proportion of sand content.

cuttings rooted mean number of of number mean

Rooting media Fig. 1 Number of Khaya grandifoliola cuttings rooted per rooting medium

3.2 Root elongation of Khaya grandifoliola per rooting media Figure 2 shows the number of roots elongation for Khaya grandifoliola cuttings stuck in the different rooting media. Significant differences were also observed among the three media in root length development of the cuttings. The highest root length was obtained in cuttings rooted in the mixed medium at a value of 8.72 cm, river sand attained the next highest root length 8.23cm and the lowest root length was observed in Loamy soil at a value of 4.007cm. The results are similar to findings of Leakey et al., (1990) and Agbo and Omaliko,(2006). cutting(cm) Mean length of rooted lengthrooted ofMean

Rooting media

Fig.2 Length of rooted Khaya grandifoliola cuttings per rooting medium. 3.3 Root formation in Khaya ivorensis In Khaya ivorensis, loamy soil recorded the highest mean number of cuttings rooted at a value of 4.16, followed by the mixture of 50% sand and 50% loam at a value of 2.41 and the lowest root numbers was recorded in river sand medium at a value of 1.31.

rooted Mean number ofcuttings

Rooting media

Fig. 3 Number of Khaya ivorensis cuttings rooted per rooting medium

3.4 Root elongation of Khaya ivorensis per rooting media Figure 4 shows the highest root length of Khaya ivorensis cutting (8.58cm) was obtained in river sand followed by the mixed medium (7.54cm) with loamy soil forming the lowest root length 5.12cm among the three media. There were no significant difference at (p > 0.05) in the number of roots and root lengths per cuttings of Khaya ivorensis (Ki) among the three rooting media. This result is related with findings by Agbo and Omaliko (2006) and Leakey et al., (1990) in which river sand was identified as the best medium enhancing the root ability of cuttings of Gongronema latifolia and Cordia alliodora respectively.

(cm) Mean length of rooted cutings cutings of rooted length Mean

Rooting media Fig. 4 Length of rooted Khaya ivorensis cuttings per medium

3.5 Survival Rate of Khaya grandifoliola cuttings Survival percentage of cuttings in each media was evaluated. The highest survival rate for Khaya grandifoliola cuttings (71%) was observed in the 50:50 v/v mixtures of river sand and loam, followed by loamy soil (60%) and river sand attained the least survival rate among the three media at a value of 51%. Statistically, there were significant difference (p > 0.05) observed between the cuttings survival among the three rooting media. This findings is related to

Survival percentage(%)

Rooting media

Fig. 5 Survival rate of Khaya grandifoliola per rooting media

4.6 Survival Rate of Khaya ivorensis cuttings Figure 5 shows the highest survival percentage for Khaya ivorensis was observed in loamy soil at a value of 61% followed by the mixed medium 53.3% and the least survival rate was observed in river sand a value of 43.3% among the three rooting media.

30 (%) 20

Mean Mean Survival percentage 0 river sand Loam 50%river sand+50% Loam Rooting media

4.0 DISCUSSION 4.1 Root formation of Khaya grandifoliola Anonymous (2007), emphasizes that in order for cuttings to form a new root system, they must have a ready moisture supply at the cut surface. The highest root formed in Khaya grandifoliola cuttings (5.92) was obtained in the 50:50 v/v mixture of river sand and loam as shown in fig. 4.2. This mixed medium’s performance was significantly different (p > 0.05) from the river sand and loam medium used solely. The highest root formation of Khaya grandifoliola cuttings in the mixed medium could be attributed to a balance in the physical and chemical characteristics of the media. This stems from the assertions of Ofori et al., (1996), that aeration and water holding capacity of the media are often negatively correlated and therefore a balance between these must be achieved to ensure optimal rooting. These finding is similar to Bhekithemba and Wahome (2010), in the propagation of Geranium (Perlagonium hortorum) where highest number of roots per cuttings (10.1) was obtained from the mixture of garden soil, compost and sand. Also, in an initial phase of Sweitinia macrophylla in non-mist propagators, Newton et al., (1993) identified a medium with sand content as capable of enhancing rooting of cuttings. The highest root formation for Khaya grandifoliola observed in cuttings rooted in the 50:50 v/v mixture of river sand and loam may have resulted from the high water holding capacity and good aeration as well as nutrient content of the medium. Loamy soil attained the lowest number of roots (3.02) formation probably due to the bulky nature of the medium as compared the pore spaces of sand medium and as such attaining higher root formation(3.07) than loamy soil.

4.2 Root elongation of Khaya grandifoliola Like root formation, the highest root elongation for the Khaya grandifoliola 8.72cm was obtained for cuttings rooted in the 50: 50 v/v mixture of river sand and loam. This could also be attributed to a balance in the media characteristics as there were significant differences among

the media performances at (p > 0.05). Loamy soil is known to contain a lot of nutrients for the roots utilization whereas sandy soil is well aerated allowing air circulation for the developed roots to lengthen easily. River sand attained the next highest root elongation (8.23 cm) as shown in fig 4.3. This observation may also be attributed to the porous nature of river sand enhancing easy spreading of the developed roots thus accounting for their higher root lengths. In terms of porosity, sand is very porous than loam probably influencing the ability of the roots to elongate easily in the river sand medium in comparison with loam. The lowest root elongation in loamy soil is in related to the bulky and reduced porosity of loamy soil resulting in reduce formation, growth and development of roots in cuttings of which Khayyat et al., (1997) affirms that reasons. 4.3 Root formation of Khaya ivorensis Similar to Khaya grandifoliola, the highest number of roots formed for Khaya ivorensis was obtained in cuttings rooted in the 50:50 v/v mixtures of river sand and loam at a value of 2.41 as shown in fig 4.3. This could be attributed to a balance in the media characteristics as noted by Ofori et al., 1996. This observations assert the emphasizes by Hartmann and Kester, (1997), that an ideal rooting media should be able to provide sufficient porosity to allow good aeration which would enhance adequate supply of oxygen availability for the developing root system in cuttings. The high aeration in the sand medium might have created a good environment for increased respiration at the base of the cuttings and encouraged rooting as there were no significant (p > 0.05) differences between the media components. Thus, the loam holds moisture while the sand keeps the medium open and well aerated.

4.4 Root elongation of Khaya ivorensis Unlike root elongation for Khaya grandifoliola in the mixed medium, in Khaya ivorensis the trend tends to vary in the sense that highest root length was observed in river sand medium at a value of 8.58 cm. Loach (1992), observed that the genetic make-up or inherent characteristics of the species may influence its response to rooting. Thus, Khaya ivorensis prefers well aerated soils naturally which probably influenced the highest root elongation 8.58cm in river sand unlike the mixed medium 7.54cm. This finding is related to Agbo and Omaliko (2006), where Gongronema latifolia cuttings rooted and elongated well in sand medium. Similar finding was made by Leakey et al., (1990), in the propagation of Cordia alliodora. The 50:50 v/v mixture of river sand and loam attained the next highest root formed and the least root length was observed in the loamy soil for Khaya ivorensis. Hartmann, (1990) and Leakey et al., (1994) emphasized that the response to rooting by cuttings in the rooting media varies among species of which contrasting results also attest. 4.5 Survival rate of Khaya grandifoliola per rooting medium Significant differences existed between the media component regarding survival rate at p < 0.05. High survival of rooted cuttings in mixed medium (71%) relates to the fact that the combination of the medium characteristics such as aeration by the porosity of sand and nutrient enrichment by the loamy soil probably favored the maximum survival rate of the cuttings. This finding is related to investigations by Ahmad and Qasim (2003), where a potting medium with sand and topsoil had maximum survival percentage of Scindapsus aureus as compared to the sole factor of each medium. The minimum survival percentage (51%) of cuttings rooted in river sand may

9 therefore be attributed to low nutrient level of the medium and the competition for nutrients posed by the numerous number of root that were formed.

4.6 Survival rate of Khaya ivorensis cuttings per rooting media Loach (1992), emphasized that some other factors could interact with media to affect growth and development of roots. The highest survival percentage for Khaya ivorensis (61%) observed in cutting rooted in loam could be attributed to the media characteristics. The stronger and more fibrous roots developed in loam might favor its ability to sustain the cuttings using its high nutrient status. For survival to occur all the resources needed by the cuttings to thrive should be readily accessible by the developed roots during growth. The nutrient status of loam utilized by the few roots formed probably might have influence the attainment of highest survival rate for the rooted cuttings. Lower survival rate (43.3%) was obtained in river sand because roots of the cuttings grown in sand media could easily be broken considering the gritty texture of sand.

5.0 CONCLUSION AND RECOMMENDATION 5.1 Conclusion From the research, 50:50 v/v mixtures of river sand and loam had the greatest influence on Khaya grandifoliola in root formation (5.92) and root elongation (8.72 cm) as compared to loam and river sand as separate entity. Highest Survival rate of Khaya grandifoliola cuttings (71%) was also obtained in the 50:50 v/v mixtures of river sand and loam. Unlike Khaya grandifoliola, Khaya ivorensis also performs better in the loamy soil regarding the number of roots formed however with root elongation, Khaya ivorensis performs better in river sand with a length of 8.58 cm as compared to the mixed medium in Khaya grandifoliola which was significantly at par at p < 0.05. In terms of survival rate, Khaya ivorensis cuttings survived best in loamy soil (61%) relative to river sand and the mixed medium. There was significant difference among the media for the Survival rate at (p < 0.05). From the study, the best rooting medium to use in the propagation of Khaya grandifoliola is a mixture of river sand and loam for numerous root formation, elongation as well as survival of the cuttings for transplanting. However, loamy soil is suitable for Khaya ivorensis regarding root formation and highest survival of the cuttings. On the other hand, if ones objective is on the root length, then river sand is the best medium for Khaya ivorensis.

5.2 Recommendation With emphasis on the aforementioned conclusion, I hereafter recommend that: 1. A 50:50 v/v mixture of river sand and loam is therefore recommended for use in commercial propagation of Khaya grandifoliola for many root formation and elongation. 2. In the propagation of Khaya ivorensis, 50:50 v/v mixture of river sand and loam is appropriate for root formation whiles river sand is best for root elongation. 3. Further work using mixtures of different rooting media with the application of growth substances should be carried out. 4. This information should be made available to foresters, farmers and plantation developers who want to embark on vegetative propagation of the two Mahoganies for plantations establishment.

REFERENCES Abbiw, D. K. (1990). Useful plants of Ghana: West African use of wild and cultivated plants. A. A. Oteng Amoako (Eds), (2006) 100Tropical African Timber Trees from Ghana.pp168-173 Graphic Packaging Accra. Agbo, C. U. and Obi, I. U. (2007). Variability in propagation potentials of stem cuttings of different physiological ages of Gongronema latifolia Benth. World J. Agric. Sci., 3(5): 576-581 Agbo, C. U. and Omaliko, C. M. (2006). Initiation and growth of shoots of Gongronema latifolia Benth stem cuttings in different rooting media. Afr. J. Bio-technology, 5(5: 425- 428)

Ahmad, I. and Qasim, M. (2003). Influence of various potting media on growth and nutrient uptake efficiency of Scindapsus aureus. Int. J. Agric. Biol., 5: 594–7.

Apertorgbor, M. M. and Bosu, P. P. (2006). An investigation of disease outbreak in a Cedrela odorata plantation in the Anhwiaso South Forest Reserve, Ghana. Report submitted to the Forest Research Institute of Ghana technical note Atuahene, S. K. N. (2001). The forest resource in Ghana and future direction of research in Hypsipyla robusta Moore (Lepidoptera: pyralidae) control in mahogany plantations. In Floyd, Hauxwell, C. (Eds), Proceedings of an International Workshop on Hypsipyla shoot bores of Meliaceae, Kandy, Sri Lanka, 1996.ACIAR Proceedingno.97, and Canberra, Australia pp.58-62. Bhekithemba, M. and Wahome, P. K. (2010). ‘Propagation of Geranium(Perlagonium horttorum?) using different rooting medium component’ American Eurasin: IDOSI Publications J. Agric and Environ. Sci., (5): 497-500. Cheesman, E. E. and Spencer, G. E. L. (1936). The propagation of cuttings in tropical climate. Trop Agriculture, Trin., 13,201 – 206 FAO. (1993). Conservation of Genetic resources in Tropical Forest Management- Principles and Concepts. FAO, Paper, 107. Rome, Italy. Griffiths, M. N. (2001). The biology and ecology of Hypsipyla shoot borers. In: Floyd, R&B Hauxwell, C. Eds), Hypsipyla shoot borers in Meliaceae: proceedings of International workshop, Kandy, Sri Lanka,August,20-23,1996.Australian Centre for International Agriculture Research, Canberra, Australia,pp77-80. Gullison, R. E., Panfill, S. N., Strouse, J. J. and Hubbell, S. P. (1996). Ecology and management of Mahogany (Swietinia macrophylla, King) in the Chimanase forest, Beni, Bolivia .Bot. J. Linn. Soc,122. Hall J. B. and Swaine M. D. (1981). Geo-botany: Distribution and ecology of vascular plant in Tropical rain forest, forest vegetation in Ghana, Dr. W. junk Publishers, London.

Hartmann, H. T., Kester, D. E. and Davies, F. T. (1990). Plant Propagation: Principle and Practices5thedn.PrenticeHall, International, Eaglewood Cliffs, NJ. Hartmann, H. T., Kester, D. E., Davies, F. T. and Geneve, R. L. (1997). Plant Propagation, Principles and Practices, 6th Edition. Prentice-Hall, Inc. Upper Saddle River, New Jersy, pp: 770. 21 International union for Conservation of Nature and Natural Resources (IUCN) (2004). Red list of threatened Species. The World’s Conservation Press Cambridge. U.K. Irvine, F. R. (1961). Woody Plants of Ghana. Oxford University Press. London. pp. 512-534 Jeruto, P., Lukhoba, C., Ouma, G. and Mutai, C. (2008). Propagation of some Endangered Indigenous trees from the South Nandi District of Kenya using cheap, Non-mist Technology. ARPN J. Agric. Biol. Sci., 3(3): Khayyat, M., Nazari, F. and Salehi, H. (2007). Effects of different pot mixtures on Pothos (Epipremnun aureum) Lindl. and Andre ‘Golden Pothos’) growth propagation by hardwood cuttings with or without and development. American-Eurasian J. Agric Environ. Sci., 6(3): 360-371. Kester, D. E., Hartmann, T. H. and Davies F. T. (1990). Plant propagation: Principles and Practices. 5th edition. Prentice Hall, Singapore, p. 647. Larsen, F. E. and Guse, W. E. (1997). Propagating deciduous and evergreen shrubs, trees and vines with stem cuttings. A Pacific Northwest Cooperative Extension Publication, Washington, USA, p. 10. Lamb, F. B. (1996). Mahogany of Tropical America: Its Ecology and Management. University of Michigan Press, Ann Arbor, MI.USA. Loach, K. (1992). Environmental conditions for rooting cuttings: importance, measurement and control. Acta, Hortic., 314:233-242 Leakey, R. R. B. (1992). Enhancement of rooting ability in Triplochiton scleroxylon by injecting stock plants with auxin. Forest Ecology and Management 54:305-313. Lemmens, R. M. H. J. (2008). In: Loupe, D., Oteng-Amoako, A. A. &Brink, M. (Eds).Plant Resources of Tropical Africa 7(1). Timbers 1 PROTA Foundation, Wageningen, Netherlands/ Backhuys Publishers, Leiden, Netherlands/CTA, Wageningen, Netherlands. pp. 333-338 Mayhew, J. E. and Newton, A. C. (1998).The Silviculture of Mahogany. CABI, Publishing; New York, NY, U.S.A. Moore, F. (1884–87). The Lepidoptera of Ceylon. 3. London, L. Reeve & Co., xv + 578 p. Newton, A. C. (1993a). Prospects of growing Mahogany in plantations. In” proceedings of the second Pan American furniture Manufactures’ Symposium on Tropical Hardwoods, Centre for Environmental Study, U.S.A. Newton, A. C., Ramnarine, S., Meson, J. F. and Leakey, R. R. B. (1993b). The Mahogany shoot borer: prospects for control. Forest Ecology and Management.57, 301-328.

Ofori, D. A., Newton, A. C. and Leakey, R. R. B. (1996). Vegetative propagation of Milicia excelsa leafy stem cuttings: effects of auxin concentration, leaf area and rotting medium. Forest Ecology and Management., 84 (1-3)39-48. Ofori Gyamfi, E. (1998). Investigation in some factors affecting vegetative propagation of Coffee( Coffee conaephera var. Robusta Pierve).Mphil Thesis, University of Cape coast Ghana. Opuni-Frimpong, E., Karnosky, D. F., Storer, A. J., Abeney, E. A. and Cobbinah, J. R. (2008). ‘Relative Susceptibility of four species of African mahogany to shoot borer Hypsipyla robusta (Lepidoptera: Pyralidae) in the moist semi-deciduous forest of Ghana’ Forest Ecology and Management, vol. 255, no.2 Opuni-Frimpong, E. (2008). Khaya grandifoliola. In: Loupe, D., Oteng-Amoako, A.A &Brink, M. (Editors). Plant Resources of Tropical Africa 7(1).Timbers 1.PROTA Foundation, Wageningen, Netherlands/ Backhuys Publishers, Leiden, Netherlands/CTA, Wageningen, Netherlands.Pp329-333 Oteng-Amoako, A. A. (Editor), (2006): 100 Tropical African Timber Trees from Ghana. Tree Description, Ethano botany and Wood Uses. Graphic Packaging Accra, Ghana. Schwabe, W. W. (1971). Physiology of vegetative reproduction and flowering. Plant Physiology, a Treatise, vol. VI (A). Editors (F.C. Steward) pp. 233-441. Academic Press, London. Snook, L. K. (2003). Regeneration, growth, and sustainability of Mahogany in Mexico’s Yucatan forests, In: Lugo A, Figueroa Coln, J.C. Alayon, M (Eds), Big Leaf Mahogany: Genetics, Ecology and Management. Springer-Verlag, New York (NY) USA, pp169-192. Swaine, M. D., Agyeman, V. K., Kyere, B., Orgle, T. K., Thompson, J. and Veenendaal E. M. (1996). Ecology of forest trees in Ghana, ODA Forest Series No.7 Taylor, C. J. (1960). Synecology and Silviculture in Ghana. The University collage of Ghana, Nelson and Sons Ltd, London, U.K. Tchoundjeu, Z., Avana, M. L., Leakey, R. R. B., Simons, A. J., Asaah, E., Duguma, B. and Bell, J. M. (2002). Vegetative propagation of Prunus africana: Effect of rooting medium, auxin concentrations and leaf area. Agroforestry Systems 54, 183 – 192 Tchoundjeu, Z. (1989). Vegetative Propagation of the Tropical Hardwoods of Khaya ivorensis (A. Chef) and Lovoa trichilioides (Harm). Thesis Submitted to the University of Edinburgh for the Degree of Doctor of Philosophy, p. 261. Wagner, M. R., Atuahene, S. K. N. and Cobbinah, J. R. (1991). Forest Entomology in West Tropical Africa: Forest Insects of Ghana. Kluwer Academic Publishers, Dochrecht Boston, London. Wilson, E. O. (1988). ‘The Current State of Biological Diversity’. National Academy Press, p. 521.