LOGISTICS OF COLLECTING 200 KG OF PINUS CARIBAEA SEED

(contributed by A.M.J. Robbins)

The following example illustrates the importance of proper planning of a seed collection so as to ensure an adequate amount of transport, personnel and equipment. Basic data is estimated for Honduran conditions (see notes at end). It is assumed that seed is collected from routine plantations with climbers and temporary storage facilities of cones based nearby, all processing being done in a central seed processing depot. Sack size is assumed to be 100 litres.

BASIC DATA | 1. | Yield of cones per average seed tree (volume) | = | 33 litres (⅓ sack) |

2. | Yield of pure seed from cones (wt. per volume) | = | 1 kg/400 litres (4 sacks) (250 g/100 litres) | |

3. | Climbing rate per climber | = | 5 trees/day | |

4. | Maximum duration of collecting season | = | 2 months, equivalent to 40 collecting days (eg 60 days less 16 (weekends) + 4 rainy days). | |

TOTAL AMOUNTS | 5. | Total wt. of seed to be collected | = | 200 kg |

6. | Total volume of cones to be collected (2) × (5) | = | 80,000 litres (800 sacks) | |

7. | Total number of seed trees to be climbed (6) ÷ (1) | = | 2,400 trees | |

8. | Total number of climber-days (7) ÷ (3) | = | 480 man-days | |

CLIMBER REQUIREMENTS | 9. | Minimum no. of climbers per day. (8) ÷ (4) | = | 12 climbers (inc. assistants = 24 collectors). |

RATE OF SACK COLLECTION | 10. | Rate of sack collection per day. (9) × (1) × (3) | = | 20 sacks |

11. | Ditto, per week (10) × 5 days | = | 100 sacks approx. | |

TRANSPORT REQUIREMENTS | 12. | Daily transport of collectors to site, + sacks on return. Must be adequate for 24 climbers, + supervisors + 20 sacks | = | 3 small pickups or 2 large pickups daily |

13. | Periodic transport of cones to seed processing depot for drying, extraction, cleaning etc. If temporary storage adequate, weekly transport would suffice. | = | 1 small lorry (100 sack load), one day a week. | |

BASIC COLLECTION EQUIPMENT REQUIREMENTS | 14. | Spurs, safety belts, ropes etc. | = | 12 sets |

Safety hats (all personnel). | = | 24 | ||

Cutters and handles | = | 12 | ||

Sacks (2 week turn around) Labels, string, etc., as required. | = | 200 | ||

PROCESSING REQUIREMENTS | 15. | Time required to sun dry cones and extract seed | = | 4 days (allowing for inclement weather) |

16. | Capacity of drying facilities to keep up with supply (11) × (15) ÷ 5 days | = | 80 sacks | |

17. | No. of tarpaulins required, 10 × 5 m. 16 sacks capacity | = | 4 tarpaulins | |

18. | No. of postmaturing storage bins (60 sack capacity) | = | 2 storage bins | |

AREA TO BE SEARCHED FOR SEED TREES | If the collection is a routine bulk collection from standard plantations, using mainly roadside trees, the following might approximate the area to be searched: | |||

19. | No. of seed trees per ha | = | 5 (estimated) | |

20. | Total area to be searched (7) ÷ (19) | = | 480 ha | |

ORGANIZATION OF COLLECTORS | The size of the collection brigades will depend on the number of vehicles available. In this example either 3 brigades of 4 climbers + 4 assistants each, or 2 brigades of 6 climbers + 6 assistants each can be transported. Each brigade can work in different areas according to crop density and time of maturity. | |||

NOTES: | Small changes in the basic data will have a large effect on labour, transport, and equipment requirements. The data given is typical for Honduran conditions, but may be different for other countries. If, for example, the yield of cones per average seed tree was up to 50 litres (instead of 33) = 1/2 sack or 500 cones, and yield of seed was up to 1 kg from 3 sacks (instead of 4), then only 600 sacks would have to be collected, equivalent to 1200 seed trees, or 240 mandays. Thus one could halve the number of collectors required, if they collect over the same no. of days, or retain the same number, and collect in half the time. |