by
Corporación Nacional Forestal
Avenida Bulnes 285 (piso 7), Santiago, Chile
During the present season the following procedure has been used for the collection of seeds of Tamarugo (Prosopis tamarugo):
1. Selection of seedtrees: In this first stage, only trees with a good seed crop and occurring in uniform stands were considered for collection. Each tree was numbered and recorded on a diagram prepared for the purpose. The other requirement for selection was that the foliage should not show any evidence of damage by disease, i.e. there should be no dieback in the foliage.
2. Collection: The pods are collected after they have fallen to the ground, which occurs normally in March. In 1984, the pods were collected in August. The following tools were used:
A fan-shaped rake to pile up the pods
A metal sieve, 50 × 60 cm, with a mesh-size of ¼" (0.6 cm). This was used to eliminate part of the litter and twigs
A shovel
A sack.
It is best to form teams of two workers, one to pile up the pods and the other to sieve them and put them into the sacks. Such a team produces 10 kg of fruit per hour. The full sacks are carried to the camp and placed in storerooms.
3. Extraction: Extraction starts by crushing the pods in a small graduated thresher with a gap of 4 mm between the stones.
This thresher is connected to a tractor, through a driving belt. To produce good results the tractor must work at low acceleration. Crushing is followed by sifting, to eliminate all the fine material. The coarse material, which contains the seeds, is accumulated in drums or other containers, awaiting the next stage, when the seeds are separated. This is done by flotation. The pieces of crushed pods float, while the seeds sink. Once the seeds have been separated, they are dried in the sun, then dusted with “Pomarsol” to prevent attack by insects, and finally placed in paper bags sealed with scotch tape.
SMALL STONE THRESHER FOR THE EXTRACTION OF TAMARUGO SEEDS
Article received in February 1985.
