SALT Agriculture 0708


S.A.L.T.-a viable solution to soil erosion in the Philippines

 

 

 

 By Aidan Rocke

 

Description and Rationale 

 

Soil erosion is an important consequence of non-terraced and poorly adapted sloping agriculture in mountainous regions in the Philippines such as Lleyte, Quezon Province, Baguio, the Tagaytay Highlands... In effect, it is the number of farms and mountain village plantations using such unsustainable practices throughout the Philippines that makes this problem so great. Soil erosion can have devastating environmental impacts such as landslides or the less dramatic loss of an important watershed or topsoil.

 

Rain forests are able to maximize the use of the shallow layer of topsoil due to an efficient recycling system that is almost leak proof. The precious topsoil is composed of a mix of mineral particles and humus, containing all the soil’s reserves of nitrogen and many other essential nutrients. Without trees this thin layer of topsoil is soon lost to torrential rains. In consequence, the livelihood of those people and communities depending on it is threatened. Often, their vegetable crops whither away and they soon seek fresh, and increasingly scarce, mountain land suitable for farming. SALT agriculture has been developed to prevent this, as it is designed to be efficient in crop production, reduce soil erosion and increase the amount of nitrogen available to crops by using special legumes for terracing.

 

The purpose of this project is to measure the effectiveness of SALT agriculture in preventing soil erosion through first hand experiments and observations on components that either indicate soil erosion or influence soil erosion. How much is known by mountain slope farmers about SALT agriculture in preventing soil erosion and if few mountain slope farmers use SALT agriculture what reasons might there be? Would it be useful and is it possible to get the Philippine government (particularly the DENR) more actively involved in promoting SALT agriculture among Filipino mountain slope farmers?

 

 Hopefully, more knowledge regarding the benefits of SALT agriculture in preventing soil erosion and example farms using this method successfully will encourage more farmers and mountain village communities in the Philippines to adopt such sustainable farming. It is hoped that the success of SALT agriculture will reduce the incidence of landslides, allow farm communities to be less dependent on costly fertilizers and money lenders, and promote consciousness of the needs of our environment which are our own.

 

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Biology

 

 

 

Common Names and Synonyms

 

Calliandra calothyrsus has several common names in its local range but it is commonly known as "cabello de angel" (meaning "angel's hair") and "barbe sol" ("the sun's beard"). In Indonesia Calliandra calothyrsus is also known as calliandra merah(red calliandra). In English it is commonly known as red calliandra or powderpuff. In Tagalog it is known as Kalgata.

 

 

Classification

 

Kingdom: Plantae (plants)

Phylum:   Magnoliophyta (flowering plants)

Class:      Magnoliopsida (Dicot flowering plants)

Order:      Fabales

Family:     Fabacae (pea family)

Genus:     Calliandra

Species:   calothyrsus

 

 

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Morphology and Physical Description

 

This small, perennial, thornless leguminous tree can grow 2-12 m high. It has a trunk diameter of up to 30 cm with white-reddish brown bark.

 

Its leaves are bipinnate and alternate. The rachis is 10-19 cm long, without glands. There are 19-60 pairs of leaflets. The leaflets are linear, oblong and acute, 5-8 mm x 1 mm. 

 

 Inflorescences are particulate  with flowers in umbelliform  clusters, 10-30 cm long.  Flower sepals and petals are green. The numerous, explosive, red staminal filaments are 4-6 cm long. 

 

Fruits are broadly linear, flattened, 8-11 cm x 1.0 cm with thickened and raised margins, finely pubescent  with 8-12 seeded.  Seeds are ellipsoid, flattened, 5-7 mm long and dark brown.

 

Calliandra calothyrsus roots have a deep and lateral rooting habit. Like many other legumes, Calliandra calothyrsus is efficient at obtaining nitrogen from the atmosphere due to a symbiotic relationship with certain Rhizobium bacteria present in the Nitrogen-fixing nodules of its root systems. Its root systems also form symbiotic relationships with vesicular-arbuscular mycorrhizal fungi which increase the ability of its roots to reach significant amounts of immobile nutrients such as phosphorus.

 

 

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Getting Food

 

 C. calothyrsus is intolerant of heavy shade. It grows in areas with an average annual rainfall of 700-3,000 mm with 1-7 dry months but does not tolerate flooding. It does not tolerate drought very well but can survive dry spells especially in riverside environments or where a perched aquifer is present. C. calothyrsus is evergreen in humid climates but semi-deciduous in areas with a long dry season.

 

It is naturally suited to slightly acidic soils of volcanic origin but also grows well on a wide range of soil types from deep volcanic loamy soil to acidic metamorphic sandy clay soil. However, C. calothyrsus does not tolerate poorly drained soils such as heavy clay soils. Using fertilizer on C. calothyrsus, especially on infertile soils, will improve its early growth and yield. However, it is often less responsive to fertilizers than some other tree legumes and often outyields other species on infertile soils.

 

C. calothyrsus obtains nitrogen and phosphorous through symbiotic relationships with Rhizobium bacteria and vesicular-arbuscular mycorrhizal (VAM) fungi in its root systems respectively. C. calothyrsus demonstrates slow early growth like many tree legumes but this may be linked to ineffective symbiosis with VAM fungi. However, once VAM fungi infections become effective it grows vigorously up to a height of 3.5 m in 6 months.

 

Reproduction

 

C.calothyrsus will flower throughout the year given sufficient soil moisture, but flowering is concentrated between October and January (late wet season).  Flowering is interrupted during the dry season if greater than 4 months.

 

Flowers bear both hermaphrodite (bisexual) and staminate (male) flowers. The level of inbreeding is influenced by age, population size and pollinator behaviour.  Pollination is achieved by hawkmoths, bats of the genus Glossophaga and other less specialised fruit bats.

 

Pod ripening occurs over several months (90-120 days). Seed ripens sequentially along the inflorescence, starting from the base. Seed dispersal happens through explosive apical dispersion of the pods.  The seeds of this tree legume have to go through scarification  before germinating. It does not grow well from stakes and is therefore generally sown directly in the field or in the nursery.

 

C. calothyrsus plantations are established by direct seeding or by seedlings, preferably planted at the beginning of the wet season. Seedlings are transplanted from nurseries at about 4–6 months, spaced at 2m x 2m or 1m x 1m.

Environmental Factors

 

This legume is a riverside colonist adapted to altitudes of 0-1850 m above sea level and tolerates mean temperatures ranging from 18-28 degrees Celsius.

 

Though it can be an aggressive coloniser of disturbed habitats, there are several pests and diseases that may harm C. calothyrsus. The scale insect infests branches and stems. Termites and borers  attack the stem. A looper eats the leaves. Fungal diseases may attack and kill plants made vulnerable through harvest wounds. In addition, Snails and rats may destroy seedlings in nurseries.

 

Genetic diversity of C. calothyrsus must be maintained in areas where it is most depended on for its various uses such as in Kenya and Indonesia so as to avoid a catastrophic social and economic disaster if a pest or disease outbreak should occur. For example, according to some sources the 1936 introduction of C. calothyrsus in Indonesia was based on only two seed samples from Guatemala which explains the lack of variation in Indonesian C. calothyrsus.

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Origin and Distribution

 

C. calothyrsus is native to humid and sub-humid regions of Central America and Mexico.  It is found from the western Pacific coast of Mexico, south throughout Belize, Guatemala, Honduras, El Salvador, Nicaragua and Costa Rica, to the north coast of central Panama covering the latitudes from 9-19ºN. C. calothyrsus was introduced into Indonesia in 1936 and most of the tropics particularly east Africa where it is now most widely used for fodder. It has also been introduced to other areas of South East Asia, Australia, Hawaii and Brazil. It is also found in the Philippines where it is used for reforestation and other purposes in Nueva Viscaya, Davao del Sur and in some provinces in Central Visayas.

 

Importance to People

 

This is a multipurpose species is grown for green manure, shade for coffee and tea, land rehabilitation, erosion control (ex. SALT), and livestock fodder. In addition, C. calothyrsus is used as a pollen source for honey production and a host for the lac insect (Laccifer lacca) for shellac production. In parts of Africa (e.g. Uganda, Rwanda) it is important in providing stakes for climbing beans. It is an excellent fuel wood because it burns well with a smokeless fire and dries very quickly (overnight for small stems).

 

Survivability and Endangered Status

 

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 C. calothyrsus is not endangered. Due to its ability to easily colonize disturbed tropical environments, rapid growth, massive reproduction, and tolerance for a wide range of soils it is rather common. In fact, this tree legume has colonized most of the tropics and in certain areas (ex. Hawaii) it is even considered a weed.

 

 

 

Potential Solutions

 

From my research I found that most mountain slope farmers know that important elements of SALT agriculture such as terracing the slope and growing tree legumes are useful in preventing soil erosion. In fact, some say SALT agriculture would be more popular if Filipinos were better informed of its benefits and given training on how to farm using this method. Most Filipino mountain slope farmers are aware that properly terraced sloping arable land, as in the case of the Banaue Rice Terraces, is beneficial in preventing soil erosion. In addition, most Filipino mountain slope farmers are aware that ipil-ipil and related species are beneficial in retaining the soil and maintaining the fertility of the soil.

 

However, many farmers argue that terracing the land demand a lot of work because it would be very difficult to carve “stairs” out of the ground because most mountain slopes in the Philippines have very shallow topsoil. This strongly supports the idea that Filipino mountain slope farmers are not well informed about SALT agriculture because the actual terracing requires little digging. In effect, the terraces naturally form due to the build up of sediment against each hedgerow of leguminous plants.

 

Compared to many South East Asian countries such as Cambodia, Vietnam and Sri Lanka that have sent delegates to the Mindanao Southern Baptist Center to learn about SALT agriculture the Philippine government (the DENR rather) has done little to promote SALT agriculture among Filipino mountain slope farmers. This is a major difference as most of the work of promoting SALT agriculture is left to Non-government organizations and so relatively few Filipino mountain slope farmers are well-informed regarding SALT agriculture.

 

It appears that the main reason why Filipino mountain slope farmers don’t use SALT agriculture is that they lack information regarding SALT agriculture. Therefore, it is important that more Filipino mountain slope farmers are informed about SALT agriculture so more Filipino mountain slope farmers would apply this method on their own plots.

 

Considering that the main issue is a lack of information on SALT agriculture among Filipino mountain slope farmers the best possible solutions should be able to diffuse information about SALT agriculture among these people in simple but effective ways. A good example would be to distribute simple pamphlets on SALT agriculture in Tagalog or even to promote SALT in a mountain slope farming community which may have a domino effect on similar communities.

 

Possibility 1

 

1) Interview an authority on mountain slope agriculture to learn more about how best to encourage Filipino mountain slope farmers to use SALT agriculture

 

Advantages:

• He/She will probably be knowledgeable about the actual circumstances of mountain slope farmers and provide

reliable information that may be useful in finding an effective way to encourage the use of SALT agriculture

 

Action Step:  

I interviewed the Mrs. Papillon , a friend of my father and manager of Pamora Farm (16:30-16:37, 5/3/08). I was hoping to learn why so few Filipino mountain slope farmers used SALT agriculture. She knows a lot about farming in mountainous areas and she has recently received a significant prize for her farming achievements from the French Government, the “Merit Agricole”. Her farm is located in the Cordilleras in Abra.

 

I asked whether she had heard about Sloping Agricultural Land Technology. She told me that she had not, but I later found that her farm grew vegetables on terraced farm systems with leguminous tree hedgerows. She used some form of SALT and she told me that an Austrian missionary, Alois Goldberger, was promoting SALT agriculture in the Cordilleras.

 

However, she told me, most Filipinos in the area still use “slash and burn” farming and other unsustainable methods. She told me this was largely due to ignorance.

 

According to her, if more Filipino mountain slope farmers were better informed about SALT agriculture and its benefits they would abandon their harmful practices. In fact, a growing number of Filipino mountain slope farmers have turned to using SALT agriculture since Mr. Goldberger has been promoting this agricultural system.

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Possibility 2

2) introduce a nearby Filipino mountain community to SALT agriculture and

help them develop a vegetable plot with SALT agriculture

 

Advantages:

• There is an agricultural community near Faith Academy that has serious problems dealing with soil erosion but its leaders know how to speak English and it has ties to Faith through the All for Jesus group

• The DERT club may help this community progress with SALT agriculture by giving some lessons to the farmers

• Some areas seem to be unused for farming due to persistent soil erosion

 

Disadvantages:

• This effort will need to succeed to have an impact on these people and will need a lot of time and planning

 

   

 -eroded arable land of the community                                                   -showing Farmer Citoy a SALT agriculture plot

Action Step:

I met with Filipinos who depended on subsistence farming near Faith Academy to introduce them to SALT agriculture. Large portions of the farmed areas appeared degraded due to soil erosion. I met with the vice president of this community, his father (who had 24 years experience in agriculture) and I interviewed Mr. Citoy (7:55-8:25, 5/3/08), who led most of the farming in their community.

 

These men had never heard of SALT agriculture but they were aware of the benefits of terracing and leguminous trees, such as ipil-ipil, in reducing soil erosion on sloping land. I decided to bring Mr. Citoy over to Faith Academy as a guest so he could see the SALT agriculture system over there.

 

While walking to the area, I that he was in charge of about 1 hectare of sloping arable land, only organic fertilizers were used to grow vegetables, and more than half the vegetables consumed in their community came from the market. I told him that their community would probably be less dependent on buying their vegetables from the market if they used SALT agriculture on their farmed land. He was a aware of problems with soil erosion and was amazed when he saw the SALT agriculture system which Mr. Bugbee had worked on.

 

He was very interested in this system of agriculture after I explained to him that the good soil in this plot was maintained by the hedgerow system and that the soil was originally no different than the soil that grew around the plot. But I also explained that though it required relatively little manual labor in the long run it demanded some hard manual labor to set up the system. Overall I found that he, the vice president and the vice president’s father were aware of many of the problems they faced against soil erosion. In fact, they had brought good soil from a dam down Valley Golf up to their area but were beginning to notice that the soil was being lost to soil erosion.

 

The vice president’s father, his son, and Mr. Citoy were all very interested to know how to use SALT agriculture for their community and even asked for plans. While I showed them how it worked in general I did not have detailed plans with me. I promised that I would help as a DERT club member in their area and that I would propose that the DERT club work to make SALT agriculture plots in their community.

 

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Possibility 3

 

4) produce a pamphlet to introduce Filipino mountain slope  

farmers to SALT agriculture in Tagalog

 

Advantages:

• Filipino mountain slope farmers will have the information they need on SALT agriculture

• Filipino mountain slope farmers will be able to access useful information in setting up a SALT system when they have time

 

Disadvantages:

• Pamphlets are not a good substitute for training which ensures that Filipino mountain slope farmers can make a SALT system

 

 

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Bibliography

 

 1) “Calliandra calothyrsus.” Tropical Forages. 7 May 2008 <http://www.tropicalforages.info/key/Forages/Media/Html/Calliandra_calothyrsus.htm>.

2) Palmer, B. “Calliandra calothyrsus.” Forage Tree Legumes in Tropical Agriculture. 7 May 2008 <http://www.fao.org/ag/Agp/agpc/doc/Publicat/Gutt-shel/x5556e09.htm>.

3) “Calliandra calothyrsus.” 7 May 2008 <http://www.fao.org/ag/aga/agap/frg/Visit/Ida/Calliandra%20calothyrsus.htm>.

4) “Calliandra calothyrsus Meissn.” Purdue University Center for New Crops and Plants Products. 30 December 1997. 7 May 2008 <http://www.hort.purdue.edu/newcrop/duke_energy/Calliandra_calothyrsus.html>.

5) <http://www.hear.org/Pier/species/calliandra_calothyrsus.htm>.

6) http://www.fao.org/ag/AGP/AGPC/doc/gbase/data/pf000470.htm

7) http://erdb.denr.gov.ph/publications/rise/r_v3n4.pdf

8) http://www.pcarrd.dost.gov.ph/cin/AFIN/technologies%20-%20salt1.htm

9) http://gina.ph/CyberDyaryo/features/cd1999_0429_008.htm

10) http://www.fao.org/docrep/u7760e/u7760e09.htm

11) interview with Mr. Citoy,a farmer and neighbor of F.A. community in Antipolo(7:55-8:25 am;5/4/08)

12) interview with manager of Pamora Farm, Arestina MORADOS-PAPILLON(16:30-16:37 pm;5/1/08)

 

 

 

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