Schinus molle

I like the name Schinus molle because it would be an excellent name for a Star Wars character, probably a crook! But it is a good example to avoid the use of common names. The Swahili name, Mpilipili is the only name used Tanzania but the other common names include Pepper tree, Chilean Pepper tree, Peruvian Pepper tree and Californian Pepper tree. Certainly the tree grows naturally in the Peruvian highlands, so South America will be its home.
The tree is tolerant to most soils and grows in warm/hot dry climates. It is drought resistant.

Description: A small tree up to about 15 metres, with drooping foliage. Usually the trunk is short and the tree has a roundish crown. Bark is dark grown/grey and flaking and sticky latex forms if the bark is damaged. Leaves are compound to 30cm with many narrow leaflets to 7cm - a pepper smell when crushed. Flowers are small and green/yellow. Fruit hanging on bunches [female trees] are small round berries pink/red when ripe.

Uses: The tree is most often used as a shelter tree, mainly shade, especially in dry areas. Grown with other (tree) crops it is said to deter termites. Firewood and charcoal tend to release pungent smoke, so is unpopular. The seeds have been blended with ordinary pepper but not in Tanzania.

Propagation: There are up to 40 000 seeds per Kg with 50% germination within 30 days. Sundry the fruit and pound with a mortar and pestle then blow away the dried flesh. There is no pretreatment necessary and seeds can be sowed directly. The seed can be stored for long periods.

I found the tree difficult to germinate in the nursery setting. It is sometimes grown as a shade crop with coffee but is susceptible to the same stem borer as the coffee plant.
Big E recommended inter-planting Grevillea robusta with Mpilipili to avoid termite attack - Grevillea is like ice cream to termites and it did not work.
Most village people see the tree as having no use other than shade and prefer more useful species, but my opinion is that a green tree is of use to the environment and in the village situation it is easier to grow as it requires less water to establish and is not browsed by goats.
The seeds can poison poultry, which is a warning, but hens usually are not interested in eating the seed.

Melia azedarach

Melia azedarach or Bead Tree and Mwarubaini nusu will grow in Tanzania from sea level to around 2000m and is often planted as an amenity tree in tropical or subtropical areas. It should not be planted near buildings though because branches break off in strong winds. But it is a useful tree in dry areas.

Description: A small tree up to 10 metres, usually deciduous. Bark is grey but when the tree is older the bark is rough and brownish with bumpy breathing pores. Leaves are compound on branched stalks up to 40 cm long, hanging in terminal bunches. The leaflets are slightly toothed. Flowers are striking lilac in clusters with each small flower having a purple centre. They are mildly fragrant. Fruits are fleshy yellow-orange, oval and in clusters. Each is 1.5cm long and they persist on the tree for a long time. Strip away the flesh to reveal a ribbed, hard bead with 4-6 black seeds inside. The seeds are poisonous.

Uses: Recommended for firewood [I have never burnt it but suggest the smoke may smell], poles, timber, bee fodder, shade, amenity, insecticide and dye.

Propagation: The species is a prolific seeder with 1 500 - 2 000 seeds per kg. They are difficult to extract because the bead is very hard. I cut the bead lengthwise and plant the half, often some seeds are damaged but others will germinate - but irregularly. In the bead, seeds will store foe two years.

The leaves are not browsed by livestock, giving a clue that people should not ingest them though a tea is used for stomach complaints - but you need to know what you are doing!
I put leaves in books and that keeps silverfish at bay. I also put leaves in bags of maize to keep weevils away and that too was successful.
To me the tree looks a bit scrawny without leaves, but for conservation it is a good tree to use. In many parts of Africa it has naturalized but I did find that harvesting seed took a long time. Looking for seedlings in the wild proved difficult and with a low transplant survival.

Azadiracha indica

Azadiracha indica is the Neem tree, or Mwarubaini kamili. And should not be confused with Melia azedarach.

The name Mwarubaini means that the tree has forty uses but in modern times the tree has been found to have around sixty.
At our nursery we found that it was too cold for the tree to perform well, though down the mountain at the King'ori turnoff some people were able to grow the species. It grows very well in the Dar es Salaam area - hot and humid.

Description: A fast growing medium-sized tree up to 20 metres high. It usually has a dense leafy canopy. Bark is grey/pale brown, grooved and rough as the tree matures. Leaves are compound, glossy green 40 cm. Each leaflet curved and pointed - saw-toothed. Flowers small and creamy white, fragrant, hanging in long sprays. Fruit are oval, yellow berries when ripe, 2 cm, thin skinned with 1 or 2 oily seeds.

Uses: Bee forage, medicinal, shade, insecticide, oil, soap manufacture.

Propagation: There are about 5000 viable seeds per kg, but seed does not store well and should be sown fresh. There is no need to strip the flesh from the berry but a nick at the round end is helpful. Because of the oily nature of the seed, it rots quickly.

The wood is tough and resistant to termites and decay.
In areas such as Dar es Salaam, wildlings can become a weed problem.
Neem oil us used extensively as as a green (organic) insecticide.
The similarity to Melia which is easy to grow in cooler areas, causes confusion and there is an expectation that it has similar uses. It has not.
Baraka made a concoction of Melia and drank it as a 'detox' - it did that alright! Harisha is the term - violent dysentery.

Sesbania sesban

Sesbania sesban - River bean - is an easily grown tree which can withstand water logging as well as dry conditions. It is quite rapid growing but has a relatively short lifespan. Sesbania can trimmed into a hedge.

Description: A short lived, sometimes deciduous shrub or tree growing to perhaps 8 metres.
Bark is red-brown and the young shoots are hairy. Leaves are compound to 12 cm with each leaflet being up to 2 cm with the tip being notched.
The flowers are yellow and speckled - in bunches.
The fruit are thin pale brown pods with seeds in separated sections so the seed rattle within.

Uses: Firewood, poles, stock fodder, shade, nitrogen fixation.

Propagation: Collect the pods which open when they are dry. There are 110 000 viable seeds per kg. The seeds can be stored for a long time. Hot water soak and direct sow. Germination 16 - 20 days (65%) therefore sow two seeds per pot.

I used Sesbania sesban as a shade tree in the nursery and did not experience it to be deciduous. I pruned to a single stem and crown out so I did not bump my head.
Sometimes a black caterpillar invaded the tree and if one fell down my neck it would itch!

One woman in Likamba used the tree as a wide-spaced hedge using the prunings to feed her zero grazed cow (a supplement really) the sticks that were not eaten, she collected and put on the low roof of her cow banga (shed). After just three days she used them in her fire to boil a sufaria of water to make tea.