HI sharan
Teak is the paragon among Indian timbers. It is a large tree that attains a height more than 30 m. Teakwood is extensively used in construction, for making door/window shutters and frames, furniture, cabinets, railway coaches and wagons, and ship/boat building. It is an ideal wood for parquet and decorative flooring and excellent wood for wall panelling. The species is indigenous to India and the Southeast Asian region. In India teak is distributed naturally in the peninsular region. It prefers a warm moist tropical climate with mean annual precipitation of 1100-2000 mm and a well-drained fertile soil. Being a strong light demander it does not tolerate overcrowding and does not withstand waterlogging.
Propagation
Seeds (fallen fruits) should be collected from vigorously growing middle-aged trees characterized by straight boles, desirable branching habit, good form and less fluting. Freshly fallen intact fruits with inflated calyx from such trees can be collected during December-February. The ground must be cleared before hand by removing litter and other materials to facilitate seed collection.
After cleaning and drying the seeds may be safely stored in gunny bags or sealed containers. Seeds of diameter greater than 9 mm are usually collected. For convenience in storage and transport, the bladder like calyx of the fruit is removed. This is done by half-filling a bag with the fruits and vigorously rubbing and shaking it or by beating with sticks, after which the remains of the calyces are separated from the nuts by winnowing. Due to hard seed coat, germination of one-year old seeds is better than that of fresh seeds.
Pre-sowing seed treatment
1. Teak seeds kept in jute sacks should be soaked in water during night time and dried in sun during day time. This practice is to be continued for one week.
2. Termite feeding: Spread the teak fruits on the ground in a 5 cm layer immediately after collection. After about five weeks the termites remove the exocarp and subsequent germination after
alternate wetting and drying is found to be better.
Nursery practices
Raised beds (30 cm high, supported with split areca stems) of 10 m x 1 m are formed. Sand and soil mixed with FYM form the top layer. Sowing is done after the bed is watered. Usually the sowing is done by broadcast method or dibbling in April-May. Seed rate is 3-5 kg of seeds per bed. After sowing, the seeds may be pressed into the beds. A thin layer of soil also can be sprinkled to cover the seeds. The beds are also mulched with green leaves to reduce evaporation losses. The bed is then dusted with carbaryl 10 per cent to prevent insect attack.
One-year-old seedlings of 1-2 cm (thumb thickness) at the thickest portion below the collar are uprooted from mother beds and used for making stumps. Stumps with 1520 cm of root at 2-3 cm of stem prepared with sharp knife are commonly used for planting. Teak seedlings can be produced in shorter duration by using polythene bags or root trainers. Three to four month old teak
seedlings are pricked out from the germination beds into polythene bags (30 cm x 20 cm) in the month of March/April. Three-month-old root trainer seedlings are also popular, of late.
Planting
With the pre-monsoon showers, stump planting is done in crowbar holes during April-May (four to six weeks before the onset of regular monsoons). The site must be cleared of stubble or other competing vegetation, if any. If containerized planting stock (polybags, root trainer) is used, then optimal time of planting may be after the onset of southwest monsoon in June-July. They are usually planted in pits of size 30 cm x 30 cm x 30 cm. Spacing recommended for monospecific woodlot is 2 m x 2 m. However, if intercrops are proposed to be raised, then row-to-row distance can be altered. For one or two row strip plantings at farm boundaries, a closer plant-to-plant spacing of 1 m could be employed initially and later thinned to attain better size.
Weeding and fertilization
Six or seven weeding may be necessary during the first two years. Teak is very susceptible to weed competition. Fertilizers may be applied @ 30-40 g N, 15-20 g P2O5 and 15-20 g K2O per plant per year from the second year to the fifth year and thereafter once in three to four years for 10-12 years. In agroforestry situations, if the intercrops are fertilized, the quantities of chemical
fertilizers applied to teak can be proportionately reduced or even skipped. Providing life-saving irrigation during the summer season favours teak growth.
Mixed plantations
Fruit/spice/medicinal trees also can be successfully intercropped with teak throughout its growth. Additionally, inclusion of nitrogen fixing trees such as Gliricidia or Leucaena (subabul) either in alternate rows or every third row not only improves teak growth but also saves chemical nitrogenous fertilizers. However, manage (by lopping or pruning) the nitrogen fixing tree component in such a way that it does not compete with teak for light.
Pests, diseases and their control
White grubs feed on roots in the nursery. Vascular wilt disease (Burkholderia solanacearum) is noticed in nursery and young plantations. As preventive measures against this disease, maintain proper drainage and avoid root injury. Leaf spot disease (Phomopsis sp. and Colletotrichum gloeosporioides) in nursery and young plantations can be controlled by mancozeb 0.05 per cent or carbendazim 0.05 per cent application. Against pink disease (Corticium salmonicolor) in young plants, apply Bordeaux paste
Defoliators (Hyblaea purea) and skeletonisers (Eutectona machaeralis) can be controlled by quinalphos 25 EC 0.05 per cent spray. However, only in small plantations / woodlots chemical control through insecticide spray is advocated. For controlling stem borer (Sahyadrassus malabaricus) apply 0.2 per cent quinalphos at the site of infection after removing the frass. Avoid
injury to root and collar to prevent bud rot and heart rot occurrence. Cut and remove the parasitic plants (Dendrophthoe falcata var. pubescens) before fruiting.
No permission is required to chop teak trees for commercial purpose.
REgards
Ashwini
