By Henrylito D. Tacio

Manila,  21 October 2009. Pili (known in the scientific world as Canarium ovatum) is an indigenous tree in the Philippines.  But despite this fact, pili is almost completely unknown among Filipinos.  Second to cashew in importance as a source of nut, it has the potential of becoming a major export crop.

Although pili is also grown in other tropical countries of Asia like Malaysia and Indonesia, only the Philippines produces and processes pili nuts commercially.  In 1977, the country exported approximately 3.8 tons of pili preparation to Guam and Australia.  Today, however, the largest buyers of pili nuts are people from Hong Kong and Taiwan as the nut is one of the major ingredients in the famous Chinese festive dessert known as the “moon cake.”

Pili, although not exploited commercially, has a whole list of advantages to farmers in less developed areas.Unknowingly, there is no commercial planting of this crop in the Philippines and fruits are collected from natural stands in the mountains near those so-called “production centers” like Bicol (particularly Sorsogon, Albay, and Camarines Sur), Southern Tagalog, and Eastern Visayas.

Pili is grown mostly for its most important product -- the kernel.  Nutritionally, it is high in calcium, phosphorus, and potassium and rich in fats and protein.  When raw, the nut resembles the flavor of roasted pumpkin seed, and when roasted, its mild, nutty flavor and tender-crispy texture is superior to that of the almond.  It is extensively used in the confectionery industry.

Pili contains approximately 23 percent oil.  The oil extracted from the kernel and husk produce a superior salad and cooking oil (which is superior to coconut oil in taste).  It can be used as base oil for bath soaps, shampoos, cosmetic, and pharmaceutical products. 

As for the stony shell, it could be developed to produce activated carbon, charcoal briquettes and as porous, inert growth medium for orchids, anthuriums and other ornamentals.

The young shoots and the fruit pulp of pili are edible. The shoots are used in salads, and the pulp is eaten after it is boiled and seasoned. Boiled pili pulp resembles sweet potato in texture; it is considered to have food value similar to avocado.

But there’s more to pili than all these.  The Botany Department of University of Hawaii describes pili as “a majestic tree” which is ideal for lining avenues, subdivisions, and golf courses.

As it is an evergreen tree with evenly spreading branches, pili is an excellent shade tree with an immediate aesthetic value.  Unlike deciduous trees, pili does not shed its leaves, making its undergrowth clean and shady year-round.  (Pili is also an excellent shade tree for abaca, coffee, cacao, and other shade-loving crops.)

Pili is also a good reforestation tree.  It is resistant to typhoons and most pests.   This hardy tree can grow in marginal lands, steep hillsides and even under coconuts.  However, it grows best in sandy loam soil rich in organic matter and volcanic soil, especially in areas where rainfall is almost evenly distributed throughout the year.

As timber, the wood is characterized by fine striated grains making it very ideal for the manufacture of high quality furniture, wall panels, carved doors, and other wooden products.  The rootstock could also be utilized for wood carvings and tool handles.

The branches make excellent firewood when dry.  The trunk produces a resinous substance commercially known as “Manila elemi,” a valuable material in the preparation of varnishes and lacquers.

Studies have shown that the average pili tree starts bearing fruits six or seven years after planting.  But given proper care and fertilization, a tree would start bearing after four or five years.  A five-year old tree yields 1,000 to 2,000 nuts per year.  The older the tree is, the more fruit it bears.

Now, are you ready to plant pili in your farm?  Here are some tips from the Department of Agriculture:

• Propagation.  Generally, it is propagated by seeds.  Seeds for planting should be selected from newly harvested fruits.  Seeds with fermented or decayed pulp should be avoided.
• However, asexual methods of propagation such as cleft grafting and inarching are preferred for cultivating high yielding mother trees.  Grafting is usually done in November to February.  The success rate range between 50 to 80 percent, depending on the physiological state of mother trees and the propagator’s skill.
• Nursery management.  A fairly level area is selected for the seedbed.  Plots – one meters wide of any length even up to five meters – are prepared.  The soil is pulverized and leveled. Compost or saw dust may be incorporated with the soil.
• The seeds are sown in parallel lines spaced about 2-3 inches apart.  The seeds are planted vertically upwards with the tapered end at the top.  Watering is employed whenever necessary.
• The seedlings are transplanted in plastic bags (5 x 7 centimeters) consisting of two parts garden soil and one part compost or coir dust.  The seedbed is watered before the seedlings are pulled singly.  Pulling should be aided by a wedge to prevent injury to the root system.
• Seedlings are ready for transplanting as soon as the pair of leaves with the cotyledon is developed.  This occurs from 30-45 days after seed sowing.
• Land preparation.  The land is plowed and harrowed once.  If planting under coconut trees, the rows are cleared by removing tree stumps.  Stakes are placed to make planting of either 10 meters x 10 meters or 12 meters x 12 meters.  Holes approximately six inches deep and 6 centimeters wide are prepared for planting seedlings.
• Planting.  Only seedlings with stem diameter of about pencil size are planted.  Two seedlings are planted 30 to 40 centimeters apart per hill.  Other seedlings are removed when trees start to bear; only female trees must be left.  A few male trees are only retained as sources of pollen.
• Fertilization.  About 100-150 grams of nitrogen fertilizer per hill are applied at least twice a year after ring weeding and within the first three years after planting.  Complete fertilizer (14-14-14) is applied from the fourth year onward.  If possible, organic fertilizer may also be applied.
• Intercropping.  In open-upland orchards, intercropping with cash crops like upland rice, corn, mung bean, peanut, yellow squash, or tomato may be done while the pili is still young.  This will ensure clean culture, while giving the farmer some income to help maintenance expenses.  After the fifth year, a perennial intercrop like coffee, cacao, black pepper or pineapple may be planted as companion crops.
• Harvesting.  Matured nuts (when fruits turn green to dark purple) are harvested by priming.  This is usually done from May to October.  However, some pili fruits do not develop at the same time.  The leftovers after the harvest season mature at different stages.  Flower initiation on the different terminal buds occur at different periods so that the late ones are harvested outside the harvest season.

Most pili kernels tend to stick to the shell when fresh, but come off easily after being dried to 3-5 percent moisture. Shelled nuts, with a moisture content of 2.5 to 4.6 percent, can be stored in the shade for one year without deterioration of quality.

According to Richard A. Hamilton, a macadamia breeder from the University of Hawaii at Manoa, the current status of the pili is equivalent to that of the macadamia some 30 years ago. As such, pili has great potential to develop into a major industry.