Tuesday, September 19

A Guide to Forest Seed Handling

A Guide to Forest Seed Handling: "In the seasonal wet and dry tropics, fire is a powerful natural factor in the removal of seedcoat dormancy. A fierce fire will kill the seeds but a light to moderate fire, such as those associated with controlled early burning, will reduce seedcoat impermeability and stimulate germination. Fire has been used in a number of countries to stimulate germination of Tectona (Laurie 1974). The fruits may be spread thickly on the ground and covered with grass which is burnt off, or they may be lightly scorched by a flame gun. Adjusting the heat of the fire to achieve the maximum effect on the pericarp without damaging the seed embryo requires experience. Similar treatment is used for Aleurites moluccana in the Philippines. The nuts are spread evenly on the ground and covered with a 3 cm thick layer of dry Imperata grass which is set on fire. As soon as the grass is burned, the seeds are placed in cold water. The quick change of temperature causes the nuts to crack and they are ready for sowing (Seeber and Agpaoa 1976). An alternative is to sow the nuts at correct spacing with only half their diameter in the soil. A layer of Imperata grass is spread over the seed bed and set on fire. After burning, the seedbed is sprinkled with water and the nuts are pushed 2 cm deep into the soil and watered thoroughly."