Precious Indigenous Woods For Coffee Shade

General – The aim of the project was to develop seedlings meeting or exceeding the criteria of success established for the current plastic bag system at the nursery and inside coffee crops. As we expected, the new system had to overcome the limitations of the old in production costs, impact on the environment, and agronomic deficiencies.

Overall, the tube container system was found to be superior to the bags in complying with the stated aims of the project. Even though, germination was not successful at the beginning of the experiment, the tube seedling health and conformation at the Toro Negro Nursery were as good as the bag trees. While the stem of the tube trees was less developed, as had been expected due to crowding, the tube products reached the same height of the bag seedlings. The predominant tree species proved to be Maga-Thespesia grandiflora), Moralón-Coccoloba pubescens and Maria-Calophyllum brasiliense ; their speed of germination and plant growth was pretty quick, up to 21, 15, and 12 inches in height respectively during the period of April 7, 2009 to September 1, 2009. Whereas, the Granadillo-Buchenavia capitata and Capa prieto-Cordia alliodora seedlings, at least the small number that achieved germination, lasted too long and grew up only from 4 to5 inches in height during this same period of time. Leaf size was not as restricted, but the caliper measurements of the trunks were smaller than hoped, though is still acceptable. Density of the roots per volume unit of growing medium was superior in the tubes.

The wood trees had been established on the coffee producing areas; 82 percent of survival was achieved at Mr. Samuel Rivera’s coffee operation unit. Some of his trees died as a result of the extended drought period of October through December 2009. Whereas, Ana Coffee Estate had 100 percent survival after 5 months of being planted inside the crop. Here, weather patterns are more favorable as this unit is located in the humid mountains of Puerto Rico, with 80 to 120 inches of rainfall throughout the year. Just a few Jacana-Pouteria multiflora exhibited a Nitrogen deficiency characterized by the appearance of a uniform yellowish color on the entire foliage. One ounce per gallon of nutrient was applied with a sprinkler water can to successfully overcome the condition within a 2 to 3 weeks period. The other farm cooperators have had similar results as their trees have been planted within the humid mountainous coffee region. Overall survival rates for this project have been quite acceptable as most of the trees have survived at the nursery and on the field. Appendix 3 illustrates photos of the tube seedlings at different stages of growth and wood trees from 12 to 30 inches in height established by the project cooperators.

On the date of the submission of this report 1090 tube seedlings were transported and planted inside the coffee crops; this is a 64 percent of the total amount of 1,700 trees that were proposed for this project. The first trees were established by the end of September 2009. In Appendix 4 we have included the agreement letters signed by farm cooperators committed to provide maintenance to the trees for the next five years period. Table 1 on next page provides detailed information concerning the wood trees distribution to project cooperators.

We are currently producing 610 tube seedlings at Toro Negro’s nursery in order to complete the total amount figure. The seeds were planted by December 2009, so we expect to have the wood trees established at the coffee producing areas by June 2010. The establishment of these trees will be made at no cost as the sub-award period of project performance ended on February 28, 2010.

Appendix 2 describes the growth rates and percent survival for the tube seedlings at the nursery and farm levels. There has been no significant increase in tree diameter as they are still at the early stages of growth. Therefore, the data has not been included in this report; we will start measuring tree diameters within the next 6 to 8 months, beginning from its first year of the growing stage.

Production costs:

Problem – Substantial tracts of land are needed to establish bag nurseries. This involves expenditures in constructing lots and access roads in the mountainous interior of the island, and the creation of infrastructure (irrigation, electrical, drainage, shade cloth houses) over a wide area.

Solution -- Tube containers reduced planting area to one seventeenth of the bag nurseries. There is more space available inside the green house. Germination boxes were eliminated.

Problem – The bag growing media must be prepared on-site using top soil and organic materials, both which are expensive and hard to procure. Manufacture of the growing medium requires heavy equipment and special machines which must be housed in large structures.

Solution – Soil was substituted by a light weight, organic, non soil medium. As opposed to manures and composts, these materials require no government permit to process or transport.

Problem – Transportation costs within the nursery, and to and within the farms are high because the bags are fairly large and heavy. The average weight of each filled bag is 8 pounds. Its volume is 226 cubic inches. A nursery worker can only carry 7 bags, weighing 56 pounds total.

Solution – Tubes decreased container weight in a 13:1 ratio, each cell weights 10 ounces. Cell volume is 40 cubic inches each; volume decreased by a 6:1 ratio. 120 tube seedlings, enough to plant 2 acres, weight no more than 75 pounds, and can be carried in a 3ft x 2ft x 2ft in height cardboard box. The coffee producers just made a round trip to transport the tube seedlings from the nursery to their farm operation. It took nearly 3 to 4 hours to pick up the trees, and 21 hours average for a farm laborer to plant 100 trees at a rate of $7.25 per hour.

Problem – Heavy use is made of expensive agricultural chemicals because of the large area involved and because the soil in bags must be treated as well and its volume is high. As the growing medium is not sterile and the bags are placed directly on the ground the rate of application and variety of agricultural chemicals is increased.

Solution – The use of agricultural chemicals, except for soluble fertilizer, was eliminated. This was made possible by lifting the crop off the ground where many pests and pathogens are concentrated, and reducing the volume of the growing medium thereby diminishing the volume of chemicals needed to treat pests and disease found in the medium. Also, an opaque plastic film was used on the greenhouse to avoid excessive dampness and appearance of fungus during the extended periods of rainfall; this would also reduce radiant temperatures inside the structure.

Problem – The bag system is labor intensive in all phases of production. This is by far the greatest cost of production in the nurseries.

Solution – Maintenance was reduced to less than 1 hour a day, it was spent mostly on hand watering. Non maintenance operations dropped from 2 months to a few days. Handling the seedlings to coffee farmers took minutes rather than hours.

Environmental Costs:

Problem --The heavy use of agricultural chemicals has been mentioned. The large areas taken up by the bag nurseries make containment of pollution difficult. Controlling runoff is not easy with the many streams present and the typical rain levels reaching 80 to 120 inches in the mountains where the nurseries are established. Puerto Rico has one of the highest population densities in the world and virtually all nurseries are located next to homes and communities, augmenting the potential for chemical harm.

Solution – Under the condition of the experiment, no chemical application was necessary. There was no special weather or other atypical situation which could account for this unexpected result, so it is felt that the result is reproducible for other tube seedling projects. The sterile growing medium prevented soil insects. Soil fungi were avoided on nearly 92 % of the seedlings through the use of sterile, aerated medium. Mollusks did not invade the seedlings because it was raised off the ground. On the other hand, the low temperatures are not favorable for their proliferation and adaptability on this Toro Negro Forest.

Problem – Conventional nurseries are wasteful of water. Ironically for such a well watered land, usable water is scarce and expensive in Puerto Rico, due to pollution, inefficient infrastructure and management. All water resources in Puerto Rico are owned by the central government and franchised to the nurseries. With the mounting pressures from a growing population, inefficient use of water in agriculture is no longer acceptable.

Solution – Because of the concentrated planting area and small container volume, the overall water use for the tubes is similar to the thriftiest system, that is, drip irrigation.

Problem – All operations within the bag nursery and seedling transportation rely heavily on the use of fossil fuels.

Solution -- Cutting back on high energy operations and equipment curtailed the wasteful use of fossil fuels. Reuse and recycling of containers and trays keep the hydrocarbons spent in producing plastic in the production chain rather than in dump or in an incinerator.

Agronomic Deficiencies:

Problem – The combination of germination in sand beds, replanting of germinates into the plastic bags, and the bags themselves promote the development of root abnormalities. These include L, J and spiral roots and multiple tap roots.

Solution – The root system of hundreds of tube seedlings were observed. Spiral and J roots occurred in none. Only field observations will reveal if this positive behavior will continue after transplant. Because of the high germination rate of the fresh wood seedlings, except for those which became sterile, direct seeding was a success, both from the speed at which it was carried out and from its agronomic benefits.

Problem – The soil based medium, particularly its clay component, does not provide sufficient porosity and related root aeration, leading to losses to damping-off disease in the early stages of seedling development. Soil porosity is 50%. A soil, peat, and sand mixture in equal parts has 55% porosity. Therefore, the inclusion of soil as a mayor ingredient (20 to 30%) in a container mix reduces porosity to unacceptable levels, when proper levels should be in the order of 80 to 90%.

Solution – Good results were obtained with the forestry industry standard mix -- formulated with peat moss, coarse grade perlite, gypsum, Dolomitic lime and wetting agent. The results obtained with this medium so far have been encouraging.