Growing Food: A Guide to Food Production

Pests: rarely a problem. Seed Weevils attack young pods and eat the developing
seed. Termites may attack young seedlings. Wild game, goats, rats, etc are also fond
of eating young seedlings, which may have to be fenced.
Diseases: seedlings sometimes die (“damping off”), but diseases are rarely a
problem.
Toxicity: Leucaena contains a toxic amino-acid, mimosine; this is most
concentrated in young, growing plant tissue—shoot tips, for example, have 10%,
while very old leaves have 1%. This may be a problem for grazing animals if
Leucaena makes up more than about 30% of their diet for some weeks.

YIELD

Grazing: 2–20 MT/ha dry matter, equivalent to 430–4300 kg/ha of protein.

UTILISATION

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carried away and incorporated into other fields. The root system is aggressive,

with a long tap root; this breaks up the topsoil and so improves water retention

and reduces erosion, while nutrients are brought up from deep down where they

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  reduces the fallow period so that the next crop can be planted earlier.

  
  

LIMITATIONS

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Symptoms: loss of hair or wool, goitres, loss of appetite, weight loss, excessive
saliva, alopecia, growth retardation, cataracts and infertility in animals.

17 m (25–35 cm diameter) in six years.

Nitrogen content, so Leucaena greatly benefits other plants which are inter-

Timber: Salvador types can grow 4 m tall in six months, 9 m in two years and

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Animal forage.

Wood—for construction, pulp and paper.

Fuel—good firewood and charcoal (high calorie content). The rotation period is

about seven years in the subtropics.

Soil improvement—leaves which fall to the ground are equivalent to manure in

cropped with it. Sometimes the leaves and young branches are cut off, then

would have remained beyond reach of other crops.

Reforestation and windbreaks.

Young pods and seeds (40–45% protein) are eaten by humans.

Shade crop, for crops such as coffee and cacao.

Support crop, for climbing crops such as Lima beans.

In shifting cultivation, Leucaena can be planted after the final crop, which

Mimosine toxicity—see “Toxicity”, above.

The plants need a fertile, well drained, non-acidic soil with low aluminium levels

Leucaena normally only grows well below about 500 m above sea level.

and high levels of phosphorus, calcium, sulphur, molybdenum and zinc.

The seedlings grow very slowly and so are often smothered by weeds.

Despite this, the plants can grow so aggressively that they become a weed.

Tsetse flies can breed in the plants, especially the more bushy Hawaiian types.

GROWING FOOD – THE FOOD PRODUCTION HANDBOOK