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A field study was carried out in two-year-old bambusetum established at main campus, Kerala Agricultural University, Thrissur, Kerala to evaluate the growth performance of selected six bamboo species of potential relevance to the humid tracts of Kerala, India. The selected bamboos included are Dendrocalamus longispathus Kurz; D. brandisii (Munro) Kurz; D. asper (Schult.f.) Back.ex Heyne\ Bambusa balcooa Roxb; B. vulgaris Schrad and B. tulda Roxb. Growth parameters such as clump height, clump circumference (at 1.37 m), culm girth (at 1.37 m), internodal length and number of culms were observed in the field at periodic intervals of four months. The field result showed considerable variation in growth and productivity among the six bamboo species under study. Overall growth performance was better for B. vulgaris, D. brandisii and D. longispathus. For instance, B. vulgaris and D. brandisii were the toppers in terms of clump height, clump circumference and culm girth while B. tulda showed relatively poor growth for these parameters. Among the species, the highest internodal length was observed for D. brandisii and D. longispathus while B. tulda recorded the shortest internodal length. Number of culms per clump was highest for D. asper while it was the lowest for B. balcooa. Faster growth rendered by all the species except for B. tulda suggest their vast potential for integration in the farm lands of Kerala for enhancing the economic and ecological benefits to the farmers. [ABSTRACT FROM AUTHOR]

Wood properties are influenced by stand management practices like thinning, pruning, etc. The implication of stand management practices on softwoods is well documented. In the case of hardwoods, the response and variation in wood properties due to thinning are still not fully understood. Twenty year old A. mangium was subjected to stand thinning at 7th year and the effect of thinning was assessed after 13 years. The wood samples collected from felled trees were analysed based on IS standards. Lack of significant variation between wood physical properties due to thinning intensities was observed. However, enhanced basic wood density which ranged from 530.50 to 602.00 g cm-3 for a 20-year-old tree was relatively higher compared to density values reported from younger aged plantations. Further, the increase in heartwood percentage (80.91%), lower moisture content and shrinkage values, all indicated that the prolonging the rotation age in fast growing species like A. mangium was more desirable from the utilisation point. [ABSTRACT FROM AUTHOR]

Initial spacing and pruning are silvicultural strategies that influence the resource acquisition capabilities of trees. A field study was conducted in the humid tropics of peninsular India to test the assumptions that: (1) high stand density of Acacia mangium induces greater root uptake capacity close to the stem and from the subsoil; and (2) crown pruning stimulates greater root uptake capacity at proximal points. Root activity pattern of two-year-old A. mangium was evaluated as a function of three population densities (1,250, 2,500 and 5,000 stems ha−1), with, and without 50% crown pruning, using 32P soil injection. The label was placed at 25, 50 and 75 cm lateral distances and at 30 and 60 cm depth. Low density stands (1,250 stems ha−1) generally showed higher 32P recovery ( P < 0.01), which was exaggerated by pruning. Pruned low density stands had 34% root activity at 25 cm, as against 23% for unpruned. The low density stands also showed higher root activity at 75 cm, signifying greater root spread. We suggest that high stem densities favour restricted spread of absorbing roots and may facilitate competitive downward displacement of roots. Pruning the lateral shoots at low stem densities may simulate this to some extent. The net outcome of interactions, however, will depend on trade-offs between stem density and tree management over time. [ABSTRACT FROM AUTHOR]

Teak (Tectona grandis L.f.) is the well-known tropical timber species to meet the demand of wood-based industries. Choosing superior parents and developing technologies for its vegetative propagation is essential for promising better growth and yield. Production of epicormic shoots on live detached branches under high humidity and temperature, is an excellent propagation option widely practiced in trees. The present study was designed to investigate the effect of genotype on the development of epicormic shoots from branch cuttings and its rooting behavior. Epicormic shoot and root production was observed to vary significantly among the genotypes studied. Initiation of bud burst started from the 5th day and continued till the 9th day of planting. The number of epicormic shoots produced too significantly varied among the genotypes. The maximum number of epicormic shoots was observed in genotypes Aravallikkavu,Topslip-6, Nellikutha-2, and Nellikutha-7, whereas Nedumkayam-1 produced one or no shoots. The average shoot diameter from different genotypes varied from 2.85 cm to 5.43 cm. Significant variation among the genotypes in rooting was observed. The highest rooting percentage of epicormic shoots was recorded in the Nellikutha-3 genotype (57.11 %) followed by Tholpatti 01 (47.89 %) and Mananthavadi 02 (39.11 %). The present study confirms the genotypic influence on vegetative propagation by varied shoot and root production potential. [ABSTRACT FROM AUTHOR]

The article offers information on the presence of invasive azedarach scale Aulacaspis crawii in India. It mentions that alien invasive species posed major economic and environmental threats that affect ecosystems, human health and economies. It also presents information on invasive species natural enemies that would lead to the biological control of the new entrant and thus minimize the economic losses.

Sawn coconut palm wood of differing wood densities (high and medium) were treated with three organic preservatives, viz., neem oil, cashew nut shell liquid (CNSL) and turpentine. The method adopted was diffusion treatment at various diffusion periods viz., 40, 80 and 120 minutes and absorption percentage of preservatives by sawn coconut wood samples (5cm×5cm×50 cm) was studied. Both high density wood (HDW) and medium density wood (MDW) samples of coconut palm showed no significant difference in absorption percentage with varying diffusion periods and no significant difference was observed between the chemicals and interaction between the chemicals and diffusion periods. [ABSTRACT FROM AUTHOR]

Vessel morphological parameters viz., vessel frequency, vessel diameter, vessel area and vessel length of anjily wood collected from trees grown in three agro-climatic zones of Thrissur district, Kerala were studied. Three girth classes were selected from each zone. Three trees representing each girth class were then chosen for collection of wood samples. Significant variation was found only among agro-climatic zones for vessel length and not between girth classes within zones. Vessel area, vessel diameter and vessel frequency did not show any significant variation between three zones as well as between girth classes. Ecoanatomical properties like vulnerability and vessel mesomorphy were also calculated. Vulnerability showed significant difference between the three zones. Vessel mesomorphy values of anjily wood indicated that the species is mesic in nature. [ABSTRACT FROM AUTHOR]