Albizia Falcataria Research Articles

Properties of molding plates made with albizia wood particles impregnated with alcohol-soluble PF resins prepared from phenol-liquefied lignins

Abstract Alkaline lignin and de-alkaline lignin were liquefied in phenol with H2SO4 or HCl as catalysts. Liquefied lignins were reacted with formalin under weakly alkaline condition, and in this manner, alcohol-soluble resol-type phenol-formaldehyde (PF) resins (PFlignin) were prepared. Small particles of albizia [Albizia falcataria (L.) Fosberg] passing 100-mesh sieve were impregnated with these resins, and the resulting molded test plates (MTPlignin) with the dimensions of 10×10×0.4 cm3 were analyzed. Differential scanning calorimeter revealed that the PFlignin resins need higher temperatures for curing than those of industrial PF resin (control). MTPlignin has higher internal bonding and bending strengths than those of the MTPcontrol. Thermogravimetric analysis of MTPs shows three distinct degradation rates, and the following heat resistance was found: MTPcontrol>MTPAL>MTPDAL. MTPs have, after carbonization at 800°C, a uniform internal structure as revealed by dimension shrinkage analysis.

異なる植栽密度で植栽した９種子産地のファルカタ（Albizia falcataria）の植栽６年目までの直径成長とピロディン貫入値の推移

異なる植栽密度で植栽した９種子産地のファルカタ（Albizia falcataria）の植栽６年目までの直径成長とピロディン貫入値の推移

UJI AKTIVITAS ANTIOKSIDAN HASIL DEGRADASI LIGNIN DARI SERBUK GERGAJI KAYU KALBA (Albizia falcataria) DENGAN METODE TBA (Thio Barbituric Acid)

Antioxidants are compounds that can delay, retard or inhibit the oxidation reaction. Lignin is a natural polymer consisting of monomeric substituted phenols. Wood lignin degradation Kalba (Albizia falcataria) yields substituted phenol. The purpose of this study was to test the antioxidant activity of compounds of lignin degradation products Kalba using TBA (Thiobarbituric Acid). Wood lignin degradation products Kalba tested antioxidant activity using the TBA method. Phase test phase of this antioxidant activity is sample preparation, determination of the maximum wavelength, determination of equilibrium time, absorbance measurements and determination of the percentage of inhibition. The wavelength maximum for BHT test solution was obtained at 530 nm. The stability of absorbance achieved after 80 minutes equilibrium time. BHT test solution and sample solution containing the degradation of lignin 0.10% (w/v) increased but not as sharp as the absorbance of control, this suggests that the degradation of wood lignin Kalba have activity as an antioxidant, which relative minimize 13,70 % compare with BHT.

A study on irritation caused by Albizzia falcataria

A study on irritation caused by Albizzia falcataria

Radial Variation of Anatomical Characteristics in Paraserianthes Falcataria Planted in Indonesia

Radial variation in anatomical characteristics of five 13-year-old Paraserianthes falcataria (L.) Nielsen (syn. Albizia falcataria (L.) Fosberg), an important commercial tree species in Indonesia, were investigated in order to obtain basic information regarding breeding for wood quality. Both cell wall thickness in wood fibers and vessel percentage showed an almost constant value up to 10 cm from the pith and then increased toward the bark. In contrast, wood fiber percentage decreased from 10 cm toward the bark. The cell wall percentage was lower towards the pith and higher towards the bark. In the five sample trees, significant differences were found in the cell diameter of wood fibers, wood fiber percentage, axial parenchyma percentage, and cell wall percentage. Basic density was affected by the cell wall thickness of wood fibers, but not the vessel percentage and fiber percentage.

Allelopathic effects of Eucalyptus urophylla on ten tree species in south China

Aqueous leaf leachate and leaf volatile of Eucalyptus urophylla were used to investigate their effects on seed germination and seedling growth of seven native tree species (Cinnamomum burmanni, Cryptocarya concinna, Machilus chinensis, Photinia benthamiana, Pygeum topengii, Diospyros morrisiana and Pterospermum lanceaefolium) and three exotic tree species (Acacia confusa, Albizia lebbeck and Albizia falcataria). It was revealed that aqueous leaf leachate suppressed the seed germination and seedling growth of Photinia benthamiana, Pygeum topengii, Diospyros morrisiana and Pterospermum lanceaefolium. In case of Cryptocarya concinna, leaf leachate decreased only the seed germination. Leaf volatile concentration beyond 250 g per desiccator had a significant suppression effect on germination of Cinnamomum burmanni, Cryptocarya concinna, Machilus chinensis, Diospyros morrisiana and Pterospermum lanceaefolium. The seedlings growth for most species was affected at concentration of 50 g and above, with the exception of Cryptocarya concinna, Pygeum topengii and Albizia falcataria which were not obviously suppressed at 50 or 150 g leaf weight. However, the growth of Pterospermum lanceaefolium remained uninhibitory till when volatile at the concentration of 350 g leaf weight was applied. From the result it can be concluded that the allelochemical effects of the donor varies with the dose applied, and species respond differently to allelochemical released by the Eucalyptus.

Impacts of a large-scale reforestation program on carbon storage dynamics in Guangdong, China

In the early 1980s, the province of Guangdong, China implemented a 10-year, large-scale reforestation program to counter environment degradation as a result of rapid economic development. Quantification of the contribution of this forest restoration program to carbon storage will provide critical information and guidance for designing future forest restoration and management strategies at the provincial level. The Guangdong Provincial Forest Inventory Database, together with our field sampling data was used to estimate carbon storage dynamics over the 10-year period of 1994–2003 for key restoration forest types as well as OBPA (open forest, bamboo forest, production forest and ambient trees). Various layers of forests were considered in calculating carbon storage: tree layers, understory vegetation and litterfall layers for the key forest types and bamboo forests; tree layers and litterfall layers for production forests; and only tree layers for open forest and ambient trees. Our results show that over the 10-year period, the reforestation program has increased total carbon storage by 41.67 Tg and forest carbon density by 1.58 Mg C ha −1. Carbon storage in tree layers was the greatest among all layers studied. Carbon storage in litterfall and understory layers amounted to approximately 38%–44% of the total carbon storage, demonstrating that litterfall and understory layers can not be neglected in estimating regional forest vegetation carbon storage in the sub-tropical forests. It was determined that coniferous forests provided the greatest contribution to total carbon, followed by broadleaved forests, OBPA, and mixed coniferous and broadleaved forests in decreasing order of magnitude. Among all key forest types, stands of P. massoniana had the greatest amount of carbon storage (from 59.65 to 65.87Tg) while Albizia falcataria (Linn.) Fosberg forest stands had the lowest (from 0.05 to 0.37 Tg). Over the 10-year period, carbon storage pools in maturescent forests, mature forests and post-mature forests were on the increasing trend, while those in young forests and middle-aged forests were declining and relatively stable, respectively. Our analysis also shows that the carbon accumulation rate in broadleaved forests (0.19–1.36 Mg ha −1 year −1) was the highest among the key forest types in Guangdong, which has important implications for selection of future forest restoration species.

A Case of Occupational Asthma Induced by Falcata Wood (Albizia falcataria)

Case: 72-yr-old manChief complaint: Breathing difficulty with wheezingwhen cutting Falcata.Personal medical history: Eczema since infancy.Tubercular pleurisy at the age of 28.Family medical history: Nothing of special note.Occupational history: Worker in wood furnitureproduction. Had been working with wood sincegraduation from junior high school.Working inpresent position since the age of 18.Smoking status: Nonsmoker, both present and past.Alcohol consumption: One bottle of beer and twoglasses of brandy every day.Pets: None.History of present illness: The patient had bronchialasthma at the age of 17. The main symptom was coughingwith slight breathing difficulty. At 30 yr of age, he wasstruck by a severe asthma attack, and was unconsciousovernight. From that time, his asthma attacks appearedonly at the turn of the season. Control by drug therapywas excellent for about ten years from when he was 60yr old, and there were no asthma attacks. The patientbecame conscious of breathing difficulty with wheezingafter entering the factory at the age of 70 yr. He began toregularly visit a local doctor’s office once a week. Hedid not have the complaint of itchy eyes. Theophyllinetablets were prescribed three times a day after each meal.Becromesazon inhalation medicine and Predonizorontablets were prescribed for use during an attack. Recently,he noticed that the symptoms appeared when cuttingFalcata with a circular saw. He could not enter the factorywhen Falcata was being cut. His symptoms appearedeven if he entered the factory without knowing thatFalcata had been cut. The severity of his symptomsgradually decreased when he left the factory and did notappear with wood other than Falcata. His symptomsdisappeared after the processing of Falcata wasdiscontinued.Two other employees also complained of sneezing,runny nose and voice change after cutting Falcata.However, they did not suffer from breathing difficultywith wheezing. Employees at other factories have alsocomplained of sneezing and runny nose after handlingFalcata.To confirm the diagnosis of occupational asthma (OA)induced by Falcata, the patient was hospitalized at theOsaka Prefectural Medical Center for Respiratory andAllergic Diseases on September 12, 2005. Signedinformed consent was obtained from the patient for thisstudy and the bronchial provocation test. This study andthe bronchial provocation test were approved by theHospital Ethics Committee. Findings on admission: Height 160.8 cm, weight 60Kg, temperature 36.5 °C, pulse 76 beats per minute, bloodpressure 140/75 mmHg, SpO

Soil phosphorus pools and supply under the influence of Eucalyptus saligna and nitrogen-fixing Albizia facaltaria

Replicated plantations of Eucalyptus saligna (Sm.) and Albizia falcataria (L.) Fosberg were examined for patterns in soil phosphorus (P) fractions and soil P availability. The supply of P was assessed in the field with anion exchange resin bags, which indicated that P supply was about twice as high under Eucalyptus as under Albizia. In the laboratory, solution P extracted with iron oxide-impregnated paper strips was also 45% higher under Eucalyptus. The effects of mixtures of the two species were intermediate between the pure-species effects. Overall, P supply either increased with Eucalyptus or decreased under Albizia. Despite significantly lower soil P availability, the Albizia plots appeared to take up and cycle as much P as the Eucalyptus plots, indicating that P supply was not independent of P demand. High rates of P uptake by Albizia may depend on higher allocations of carbohydrate to belowground production.

The contribution of Paraserianthes (Albizia) falcataria to sustainable swidden management practices among the Baduy of West Java

There is a prohibition on the use of modern external inputs, such as chemical fertilizers, in Baduy swidden farming. Ordinarily, the consequence of this in a situation of acute forest pressure would be a decrease in fallow times, and an inevitable depletion of soil fertility. The Baduy (particularly Outer Baduy) have several ways of alleviating this problem, one of which is the introduction of Paraserianthes (Albizia) falcataria. By alternating this commercially valuable perennial leguminous tree with rice, soil fertility is maintained and the socio-economic position of the Baduy improved. As a result, swidden farming, which is considered by the Baduy to be central to their cultural identity, continues to be viable, despite increasing population density and the continuing depletion of mature forest.

STUDIES ON NATURAL PRODUCTS OF ALBIZIA SP.

The bark of Albizia lebeckioides and Albizia falcataria have been examined for their chemical constituents. A. lebeckioides has yielded the steroidal ketone, stigmasta-4,22-dien-3-one, and a triterpene alcohol as the major neutral components. A. falcataria has yielded a similar triterpene and fatty ester as its major constituents. The toxicity of the compounds was evaluated in bioassay against termites. The results showed that lupenone and stigmastadienone were toxic ioNeotermes dalbergiae species. In contrast these compounds were less toxic to Cryptotermes cynocephalus species. Key words: Insecticidal plants / Albizia lebeckioides I Albizia falcataria I Bark / Extracts / Chemical constituents / Toxicity / Termites

Effect of Eucalyptus saligna and Albizia falcataria on soil processes and nitrogen supply in Hawaii.

This study investigated the differences between two fast-growing tropical tree species on soil N flux and availability. The work was conducted in the island of Hawaii and included three sites located along the Hamakua coast on the northeastern side of the island. Within each site pure stands of Eucalyptus saligna (Sm.)␣and the N2-fixing Albizia falcataria (L.) Fosberg [=Paraserianthes falcataria (L.) Nielsen] were arranged in four randomized complete blocks. For most of the variables considered in this study, the species effects were usually strong and the site effects were significant in some cases. After 13 years, soils under the Albizia stand contained larger pools of total soil C and N, and larger pools of inorganic N. Soil N availability indexed by ion exchange resin bags revealed a strong pattern of species and site effect on N availability; soils under Albizia showed a 2.6-9 fold increase in N availability (P < 0.01). Potential net rates of N transformation (10- and 30-day aerobic incubations) were more than twice as high for soils under the Albizia than under the Eucalytus stands. Nitrogen mineralization during anaerobic incubations were about 10% greater on Albizia soils. Gross microbial mineralization and immobilization were determined by estimating the gross rates of N transformation by the 15N-isotope pool dilution techniques. Across species and sites, a strong linear positive relationship was obtained for gross immobilization and gross mineralization indicating faster gross immobilization as gross mineralization increases. Soil microbial biomass on Albizia soils contained larger proportion of it as bacterial biomass, while larger proportion of fungi biomass comprised the microbial biomass under Eucalyptus soils. This study clearly showed that the presence of Albizia increased total N pools and N supply to the ecosystem. The overall effect on soil fertility will need to be characterized by the effect of the N2-fixer on other nutrients, especially the effect on phosphorus.

Growth, Development, and Yield in Pure and Mixed Stands of Eucalyptus and Albizia

Abstract Productivity of Eucalyptus saligna Sm. plantations is commonly limited by low levels of available nitrogen (N), and synthetic N fertilizer applications are costly and sometimes impractical; thus, we evaluated mixed species plantings in which N is added by Albizia falcataria (L.) Fosberg [=Paraserianthes falcataria (L.) Nielson]. Five ratios of Eucalyptus and Albizia were compared with each other, with pure Albizia, and with pure Eucalyptus fertilized periodically with N in a randomized block design on the wet Hamakua coast of the Island of Hawaii. Eucalyptus growth increased as the amount of Albizia in the stand increased from 11 to 66%, and heights and diameters of Eucalyptus in stands containing 34% or more Albizia were equal to or larger than those in fertilized, pure stands. Total aboveground biomass, stem biomass, and stem volume per ha of mixed stands at age 10 were at least equal to yields produced in fertilized, pure Eucalyptus stands; total biomass of mixed stands with 50 or 66% Albizia was 30 and 46% greater than that in fertilized, pure Eucalyptus and 10 and 24% greater than that of pure Albizia. Yield of the Eucalyptus component alone in these two mixtures was at least equal to that of fertilized, pure Eucalyptus stands. Moreover, mean annual increment declined more slowly after culmination in all-mixed stands than in the fertilized, pure Eucalyptus stand. Over time, the apparent benefits of mixed versus pure plantings of Eucalyptus and Albizia have increased, and at age 10 include diversity in stand structure (and habitat) as well as the improvements in Eucalyptus tree growth and stand productivity recognized at younger ages. For. Sci. 43(2):286-298.

Bioassays of the influence of Eucalyptus saligna and Albizia falcataria on soil nutrient supply and limitation

Replicated plantations of Eucalyptus saligna (Sm.) and Albizia falcataria (L.) Fosberg [ = Paraserianthes falcataria (L.) Nielsen] in Hawaii allowed an assessment of 12 years of influence of each species on soil fertility. Bioassays with Eucalyptus and Albizia seedlings showed that each species of seedling grew better in soil from the plantations with the other species. The nutrient content of seedlings showed that soils under the influence of Albizia had higher supplies of available N, but lower supplies of available P. Albizia seedlings were strongly limited by P supply in the soils from either species, whereas the growth of Eucalyptus seedlings was limited by both N and P. Albizia seedlings fixed > 95% of the N they used, and took up less soil N than did Eucalyptus seedlings. The overall pattern indicated that Albizia increased soil N supply and growth of Eucalyptus seedlings, although the higher supply of N was not enough to remove N limitation on growth. Albizia also reduced the P supply of the soil, and Albizia seedlings were strongly P-limited regardless of the plantation species. The long-term productivity of tropical plantations depends on continued supplies of nutrients, and these supplies may be strongly influenced by the species selected for plantation use.

Effects of Dinitrogen‐Fixing Trees on Phosphorus Biogeochemical Cycling in Contrasting Forests

AbstractPhosphorus availability in soils is controlled by both geochemical and biological reactions. Dinitrogen‐fixing trees differ from non‐N2‐fixing trees in litter production and litter chemistry, and these differences may substantially alter soil P biogeochemistry. We examined the effects of two N2‐fixing tree species on labile P pools and potential P transformation rates and correlated these variables with soil acid phosphatase activity. Experimental treatments include stands of N2‐fixing red alder (Alnus rubra Bong.), conifers, and a mixture of both in Oregon, and plantations of N2‐fixing Albizia falcataria (L.) Fosberg, Eucalyptus saligna Sm., and a mixture of both in Hawaii. Data from Oregon indicated that red alder increased labile organic P (Po) levels and soil phosphatase activity. Soil labile Po concentrations in the red alder and mixed stands were twice those of the conifer stand. Labile inorganic P (Pi) pools and net P solubilization rates in soils under the mixed stand were two‐ to fivefold greater than in pure stands, suggesting that interactions between alder and conifers, rather than alder's effect, triggered changes in P geochemical reactions. In Hawaii, labile Po concentrations in both pure A. falcataria and mixed plantations were higher than in the pure E. saligna plantation. Soil acid phosphatase activity in the pure A. falcataria plantation was twice as high as that in the pure E. saligna plantation. However, labile Pi pools and P transformation rates did not differ among the three Hawaiian plantations. Our results suggest that N2‐fixing trees increase soil labile Po levels and soil phosphatase activities whereas their interactions with non‐N2‐fixing trees vary with species and may result in altering both geochemical and biological P transformations.

Performance of multipurpose trees for agroforestry two years after planting at Makoka, Malawi

Forty-nine accessions of multipurpose trees belonging to 37 species were planted at Makoka, Malawi, on a ferric lixisol at 1030 m altitude, unimodal rainfall (average 1044 mm per annum) and a dry season lasting 6 months. Two years after planting, 25 accessions showed > 90% survival and most fast growth and high biomass production. The ranges of growth parameters in these accessions were 3.2–7.1 m height, 7.0–15.4 cm collar diameter, and 18–40 t ha −1 total above ground biomass. Potential biomass production obtained from coppice regrowth in the best accessions was 5.0–13.7 t ha −1 per year. The best performing species were Calliandra calothyrsus, Acrocarpus fraxinifolius, Gliricidia sepium, Cassia spectabilis, Cassia siamea, Flemingia congesta and Albizia falcataria. of the 18 Australian species tested, only Acacia auriculiformis, Acacia shirleyi and Acacia julifera showed satisfactory growth. Cassia brewsterii, Acacia ampliceps and Acacia victoriae failed to grow. Other species showing poor performance included Prosopis species and Robinia pseudoacacia.

Use of an Exotic Tree Plantation by Bornean Lowland Forest Birds

ABsTRAcr.-During May to July 1982, we surveyed birds in primary forest and in differentaged groves of the exotic tree Albizia falcataria at Sabah Softwoods, a lowland tree plantation in Sabah, East Malaysia (formerly British North Borneo). We found that the Albizia was in general attractive to many native birds. About 60% of primary-forest species used the plantation, and the frequency at which individuals were observed in the oldest groves was almost twice that of nearby primary forest. The Albizia attracted birds because, as an extremely fastgrowing legume with thin leaves, it permitted the rapid development of a well-structured secondary forest. It also was heavily infested with pest insects, which provided an abundant food source. Despite its apparent richness, however, the Albizia lacked several important features of natural forest (e.g. canopy fruits and nest holes). As a result, some primary-forest bird groups were poorly represented (e.g. large canopy frugivores and flycatchers) and others could make only limited use of the plantation (e.g. woodpeckers). In addition, the Albizia is expected to lose its diversity as the plantation as a whole ages. Many of the plantation birds were transients from nearby forest that visited daily to feed, and some probably had been displaced by intense logging. The number of daily transients should decrease as primary forest recedes due to logging and development. Refugee species diversity should suffer from attrition as the plantation is cropped and predation and age take their toll. Received 9 March 1992, accepted 20 November 1992.

Growth of forage tree legumes at four agro-climatic sites in Indonesia

SUMMARYThe growth of the tree legumes Leucaena leucocephala, Gliricidia sepium, Sesbania sesban, Sesbania grandiflora, Albizia falcataria and Calliandra calothyrsus was evaluated at four sites in Indonesia between 1984 and 1986. Tree seedlings were planted at 10000 trees/ha and, after an establishment period of 9–12 months, harvested every 3 months for a 2-year period.At Bambu Apus, West Java (2040 mm annual rainfall, 1 month dry period, lowland, latosol with pH 5·6 decreasing with depth), G. sepium and C. calothyrsus produced 13 and 10 t/ha per year of leaf dry matter, respectively. Other species did not grow well at this site and fewer than 60% of the trees of these species survived until the end of the experimental period. At Sei Putih, North Sumatra (1550 mm annual rainfall, 3 months dry period, lowland, podzolic with pH 5·5 increasing with depth), no species produced &gt; 6 t/ha per year of leaf dry matter. The highest yielding species were L. leucocephala and A. falcataria. At Cisarua, West Java (3340 mm annual rainfall, no dry periods, 925 m altitude, latosol with pH 5–6 increasing with depth) only C. calothyrsus grew well and produced 9 t/ha per year of leaf dry matter. At Grati, East Java (1500 mm annual rainfall, 6 months dry period, lowland, alluvial with pH 6·6 increasing with depth) L. leucocephala produced &gt; 8 t·ha per year of leaf dry matter, while none of the C. calothyrsus and A. falcataria trees survived the first dry season.Although L. leucocephala has been the most widely grown tree legume species in the tropics, C. calothyrsus and G. sepium performed better at the wetter sites and at high altitude.

Species effects on earthworm density in tropical tree plantations in Hawaii

Tree species differ in the quantity and quality of litter produced, and these differences may significantly affect ecosystem structure and function. I examined the importance of tree species in determining earthworm densities in replicated stands of Eucalyptus saligna Sm. and Albizia falcataria (L.) Fosberg, and in mixed stands (25% albizia and 75% eucalyptus). Mean earthworm densities ranged from 92 m-2 in the pure eucalyptus, to 281 m-2 in the mixture, and a maximum of 469 m-2 in the pure albizia stands. Only two earthworm species were present, Pontoscolex corethrurus and Amynthas gracilis. Leaf biomass on the forest floor was highest in the pure eucalyptus and lowest in the pure albizia stands, whereas the annual fine litterfall production was lowest in the pure eucalyptus and highest in the albizia stands. The N content of fine litterfall was correlated positively with earthworm density, and the fine litterfall biomass: N ratio was correlated negatively with earthworm density. Greater leaf biomass on the forest floor under eucalyptus stands despite lower rates of litterfall suggests that litter quality, rather than litter quantity, was primarily responsible for the greater earthworm density in the albizia stands. Some biogeochemical effects of tree species in the tropics may be mediated through effects on earthworm populations.

Chemical constraints to the use of tropical legumes in animal nutrition

Browse and grain legumes offer considerable potential for enhancing animal productivity in the tropics. However, a major factor limiting the wider use of these plants is the ubiquitous distribution of a diverse array of natural compounds which are capable of precipitating adverse effects in animals. Manifestations of toxicity range from a marked reduction in animal performance and nutrient utilisation to profound neurological effects and increased mortality. This review identifies the primary anti-nutritional factors in tropical legumes and evaluates the prospects for their detoxification. Although protease inhibitors are widely distributed in legume forage and grains, their role appears to be secondary to that of other toxic compounds. Recent studies highlight the dominant impact of lectins in determining the nutritional value of seeds of Psophocarpus tetragonolobus (winged bean) and Canavalia ensiformis (jack bean). The presence of condensed tannins is a characteristic feature of many browse legumes, including Gliricidia sepium, Acacia species, Leucaena leucocephala and Albizia falcataria. These polyphenolic compounds are sometimes accorded with beneficial attributes in ruminant nutrition by virtue of their capacity to suppress bloat and to prevent excessive degradation of high-quality leaf protein in the rumen. However, with respect to the condensed tannins of tropical forage legumes, there is increasing evidence of toxicity in all classes of livestock, including ruminants. The occurrence of toxic non-protein amino acids is a distinguishing feature of many forage and grain legumes. These amino acids contribute significantly to the toxicity of Leucaena leucocephala, Canavalia ensiformis and Lathyrus species. The distribution of several anti-nutritional factors in a single legume species causes difficulties with detoxification, particularly if the deleterious compounds are heat stable. Significant experimental procedures have recently been described for the detoxification of the winged bean and the jack bean, and these methods now await economic appraisal. The treatment of harvested leaves or the spraying of leguminous shrubs with polyethylene glycol (PEG) to alleviate the deleterious effects of condensed tannins is a comparatively recent innovation worthy of further investigation, particularly in view of striking improvements in the performance of sheep fed Acacia aneura. The most no'able advance in detoxification relates to biotechnological manipulation of rumen function, enabling cattle grazing Leucaena forage to degrade the deleterious amino acid, mimosine, to innocuous residues. The prospects for exploiting this technique in the detoxification of other tropical legumes and forage plants hould now be considered. However, the scope for any significant role of leguminous leaf meals in the utrition of non-ruminant animals now appears to be limited, despite recent advances in detoxificaion. In the case of these feedingstuffs, the major constraints are the intrinsic low digestibility of the protein fraction and the inferior metabolisable energy content relative to that of the legume grains.