Dr Abe V Rotor
Sample of ipilipil branch infested with plant hopper, Psylla, shown in nymphal stage under the microscope. (50X magnified)
Ipil-ipil (Leucaena glauca), the miracle tree in the sixties and seventies has provided Filipinos much hope for cheap wood, fuel, paper, board, feeds, compost, and in reclaiming our denuded forests and wastelands.
The Department of Agriculture came up with a “litany” on the miracles about this tree. Ipil-ipil as a new source of dendrothermal power; ipil-pil for high-protein component feed for poultry, piggery and livestock; ipil-ipil as construction material, scaffolding, pole, furniture, toothpick, matchstick – to name a few.
As Forest Wood
Substitute
On closer look the secret of success of the native variety is its tap root system. Few trees can grow on rock with their penetrating deep through cracks in order to reach deep-seated water. In the process, they pry off the rock itself helping in weathering it. And if it is adobe rock, the locked up nutrients are released as soil formation progresses. One drawback of the native variety however, is its high mimosin content.
“Don’t allow the goats to browse too much on ipil-ipil,” my father used to remind me on the farm. I would then secure the rope that restrains the animals feeding in the open. Years later I found out that the warning is based on the fact that mimosin causes poor growth (bansot) and falling of hairs in animals. Early balding is believed to be one of the effects of drinking coffee clandestinely mixed with ipil-ipil seeds.
Initial experiments show that mimosin can be made into pesticide against weeds, insects and pathogenic fungi. It has been also observed that it repels insects such as flies and mosquitoes.
Re-vegetation of Corrigidor Island by Ipil-ipil
Ipil-ipil can be used in the manufacture
of organic fertilizer to reduce our dependence on imported chemical
fertilizer. It is also used for
rip-rapping, terracing and strip cropping to save our lands from erosion and
desertification. It is an excellent
source of firewood and charcoal for many homes.
Ipil-Ipil “Gold Rush”
The ipil-ipil fever spread throughout the country that no home lot or farm was virtually without this leguminous tree.
Plantations sprouted. As a biologist I know that there are nitrogen-fixing
bacteria (Rhizobia) which reside in
its roots, adding to the fertility of the soil.
With the tree continuously shedding off its leaves, there is free mulch
with which to conserve water and control weeds choking the plants intercropped
with the tree. Along levees four to six rows of ipil-ipil could effectively
serve as windbreak, buffering strong winds and filtering the sand and dust that
affect sensitive field and garden crops.
Ipil-Ipil “Gold Rush”
Because the wood is white, soft, and
uniform grained, many entrepreneurs tried making toys and decorations such as
fans, spin tops, picture frames, knife handles out of it. Since it is easy and
fast to grow, it helps in conserving forest trees. This means we can spare
harvesting our forests’ reserve. We can
keep our narra, almaciga, apitong, and mahogany that are
considered rare. Ipil-ipil is also a
good substitute of acacia, a favorite of woodcarvers.
Because of its success as a plantation
crop in Hawaii and Peru, we did not only import its technology, we introduced
its varieties into the country, in favor of our own native variety which is
small. In fact one would consider it a
mere shrub which happens to be growing in places where no other plants grow,
usually on scrubby and inclined slopes, wasteland where only the sturdy talahib and bamboo grow. The early uses for native ipil-ipil are
firewood and bean poles.
On closer look the secret of success of the native variety is its tap root system. Few trees can grow on rock with their penetrating deep through cracks in order to reach deep-seated water. In the process, they pry off the rock itself helping in weathering it. And if it is adobe rock, the locked up nutrients are released as soil formation progresses. One drawback of the native variety however, is its high mimosin content.
“Don’t allow the goats to browse too much on ipil-ipil,” my father used to remind me on the farm. I would then secure the rope that restrains the animals feeding in the open. Years later I found out that the warning is based on the fact that mimosin causes poor growth (bansot) and falling of hairs in animals. Early balding is believed to be one of the effects of drinking coffee clandestinely mixed with ipil-ipil seeds.
Initial experiments show that mimosin can be made into pesticide against weeds, insects and pathogenic fungi. It has been also observed that it repels insects such as flies and mosquitoes.
Re-vegetation of Corrigidor Island by Ipil-ipil
Our native ipil-ipil is perhaps the first plant used for rehabilitating wastelands in the countryside. Immediately after the war, sacks of native ipil-ipil seeds were air dropped on Corrigidor island at the onset of the rainy season. The project facilitated the re-vegetation of the war-torn island, and prevented it from further destruction, this time from the ravages of erosion.
What Wiped Out Ipil-ipil?
Psylla infested ipilipil trees cut into firewood.
First, it establishes a foothold on the young leaves and shoots, where it builds a colony. Being highly prolific the colony can explode into thousands of insects inside of a few weeks, nurtured in all stages of development by the virtually endless supply of nutrients from the growing tree.
The final blow comes when the insect drains the tree sap dry, stopping the growth of healthy shoots to replace the dying ones. Interestingly the bigger the tree is, the more it is prone to attack and eventual starvation.
Homopterans are among the most adaptable of all insects. They are very small, reproduce rapidly and can adopt through seasons through alternate tree hosts. Having studied their unusual reproductive development, I have found that when stressed for food or due to a harsh environment, they can shorten their life cycle to accelerate reproduction. Under extreme conditions they either lay eggs prematurely or directly bear young. Sometimes nymphs can reproduce. Biologists call this phenomenon, paedogenesis.
Abandonment of Ipil-ipil Projects In the late 1970s many farms of ipil-ipil were laid waste by the insect. Owners cut down the trees prematurely. Tree, after tree, was felled not by the ax but by the ravages of the pest. But our own native ipil-ipil stood healthy, a proof of genetic resistance of the indigenous variety.
_____________________________________________________________
Whatever happened to the ipil-ipil manifests a syndrome in agriculture where the concept of economic benefit and comparative advantage, can bring about neglect in plants and animals – and even to projects and programs, primarily for failing to meet desired standards and parameters. But the worst kind of neglect is that which follows the failure of science and technology to promised results.
_______________________________________________________
Breathing Time for Nature to Heal Three decades had passed since those devastating infestations. Alone, the ipil-ipil had only one resort of recovery - through the healing power of nature. Nature knows best when left alone.
Happily the pollinators had been transferring the resistant gene of the native species to the more susceptible varieties, while certain desirable traits of the latter were transferred to the native variety. In both cases, natural cross breeding slowly took place without us noticing. Only nature knows the future of open and random pollination.
Natural Ipil-ipil Hybrid It may not be important to give the hybrid a name, for there must be a number of genetic types. We do not know how many genes there are and whose genes they carry. Amazingly as we examine the shoots and young leaves of these new trees, even while finding the culprit around, the trees keep fighting back apparently due to a developed resistance mechanism.
Schools of thoughts will be brought out as this article is read and shared. Among them are the following:
1. It is possible that the insect is undergoing a long-term, high-level virulence. Are we currently experiencing its low level?
2. Could it be that due to massive cutting of ipil-ipil trees, the principal host is no longer of sufficient quantities to maintain the pest in its epidemic rampage?
3. Could the insect have shifted to some other alternate host more suitable to them?
4. Since only areas favorable to ipil-ipil remain, the pest is not noticeable where ipil-ipil is sporadically growing.
5. Predators of Psyllids must have developed through the years, which now limit the pest population within the threshold level.
These hypotheses may serve as a basis for discussion, research and experimentation, but what is more important to know is that the return of ipil-ipil is evidence of Nature’s triumph. ~
What Wiped Out Ipil-ipil?
With the introduction of Hawaiian and Peruvian ipil-ipil varieties, the expected performance level in terms of fast growth, adaptation and yield were achieved. This stimulus caused universal acceptance of the new crop, creating a new field in agriculture: dendrothermal (or firewood) farming.
But the boom was short lived. Nobody knew that the foreign varieties also carried with them a deadly pest – the leafhopper of the genus Psylla of the Family Psyllidae, Order Homoptera, the same group of insects that are the scourge of many agricultural crops, such as the tungro leafhopper, aphids, scale insects and mealybug.
Cause of Widespread
But the boom was short lived. Nobody knew that the foreign varieties also carried with them a deadly pest – the leafhopper of the genus Psylla of the Family Psyllidae, Order Homoptera, the same group of insects that are the scourge of many agricultural crops, such as the tungro leafhopper, aphids, scale insects and mealybug.
Cause of Widespread
Infestation In biology, natural enemies control a pest. If the enemies are not around, the pest multiplies rapidly. Despite quarantine procedures, the Peruvian and Hawaiian varieties carried the Psylla insect from their port of origin. Unlike in their native countries abroad, this pest while here, lost its natural predators. Thus the insect began to multiply to epidemic proportions. Thousands of trees, and plantations, succumbed to the pest.
This is how the pest attacks.
This is how the pest attacks.
First, it establishes a foothold on the young leaves and shoots, where it builds a colony. Being highly prolific the colony can explode into thousands of insects inside of a few weeks, nurtured in all stages of development by the virtually endless supply of nutrients from the growing tree.
The final blow comes when the insect drains the tree sap dry, stopping the growth of healthy shoots to replace the dying ones. Interestingly the bigger the tree is, the more it is prone to attack and eventual starvation.
Homopterans are among the most adaptable of all insects. They are very small, reproduce rapidly and can adopt through seasons through alternate tree hosts. Having studied their unusual reproductive development, I have found that when stressed for food or due to a harsh environment, they can shorten their life cycle to accelerate reproduction. Under extreme conditions they either lay eggs prematurely or directly bear young. Sometimes nymphs can reproduce. Biologists call this phenomenon, paedogenesis.
Abandonment of Ipil-ipil Projects In the late 1970s many farms of ipil-ipil were laid waste by the insect. Owners cut down the trees prematurely. Tree, after tree, was felled not by the ax but by the ravages of the pest. But our own native ipil-ipil stood healthy, a proof of genetic resistance of the indigenous variety.
_____________________________________________________________
Whatever happened to the ipil-ipil manifests a syndrome in agriculture where the concept of economic benefit and comparative advantage, can bring about neglect in plants and animals – and even to projects and programs, primarily for failing to meet desired standards and parameters. But the worst kind of neglect is that which follows the failure of science and technology to promised results.
_______________________________________________________
Breathing Time for Nature to Heal Three decades had passed since those devastating infestations. Alone, the ipil-ipil had only one resort of recovery - through the healing power of nature. Nature knows best when left alone.
Happily the pollinators had been transferring the resistant gene of the native species to the more susceptible varieties, while certain desirable traits of the latter were transferred to the native variety. In both cases, natural cross breeding slowly took place without us noticing. Only nature knows the future of open and random pollination.
Natural Ipil-ipil Hybrid It may not be important to give the hybrid a name, for there must be a number of genetic types. We do not know how many genes there are and whose genes they carry. Amazingly as we examine the shoots and young leaves of these new trees, even while finding the culprit around, the trees keep fighting back apparently due to a developed resistance mechanism.
Schools of thoughts will be brought out as this article is read and shared. Among them are the following:
1. It is possible that the insect is undergoing a long-term, high-level virulence. Are we currently experiencing its low level?
2. Could it be that due to massive cutting of ipil-ipil trees, the principal host is no longer of sufficient quantities to maintain the pest in its epidemic rampage?
3. Could the insect have shifted to some other alternate host more suitable to them?
4. Since only areas favorable to ipil-ipil remain, the pest is not noticeable where ipil-ipil is sporadically growing.
5. Predators of Psyllids must have developed through the years, which now limit the pest population within the threshold level.
These hypotheses may serve as a basis for discussion, research and experimentation, but what is more important to know is that the return of ipil-ipil is evidence of Nature’s triumph. ~
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