Pithecellobium dulce

Pithecellobiun dule is a good example why botanical names are much more precise than common names. The English name, Madras thorn is copied in Swahili by mkwaju wa kihindi [Tamarind of India] but the tree actually comes from tropical America!
It tolerates drier and less fertile areas because it fixes nitrogen which helps it survive the rigors of climate. However it also grows well in places like Dar es salaam, where I collected most of our seed.

Description: A thin, shrub with no apical dominance, but also grows to a large, muli-branched tree to 15 metres. It carries sharp, thin spines at the base if each leaflet and sometimes on branches. Bark is pale grey/brown, smooth with horizontal marks. Leaves are on thin stalks with two pairs of leaflets, each >5cm, rounded with the tip notched. Flowers are small and cream - yellow with green/white stamens. In bunches and on short stalks. Fruit are heavy, twisted pods <12cm, constricted between seeds. Red when Mature and splitting to release glossy black seeds surrounded by a red and white fleshy edible aril.

Uses: Firewood, timber and poles - soft and easy to work and durable, food and drink from the fleshy aril, fodder - pods and leaves, bee forage, soil conservation, shade, live fence [trimmed], gum from the bark and oil from the seeds.

Propagation: There are >20 000 seeds per kg and can be stored for up to a year. Seeds can be direct sown after soaking in water for 6 hours, resulting in 95% germination after 2 weeks.

I have not seed the fruit used as a food except for young kids in Dar es Salaam. Rural people do not seem to trust the fruit whereas in India it is well known.
I suspect the species could become a weed because of its ability to colonize less productive areas - I am not sure about my attitude to this.
Spines in the nursery make it a little uncomfortable to work with sometimes.
If pods are not collected by people livestock and monkeys soon clean them up.

Carica papaya

Papaya, pawpaw or in Swahili, Mpapai is not actually a tree, rather a herb that can grow up to 8 metres. It is a short lived tree grown in mild tropical climates and performs best in Tanzania under 1500 metres above sea level but will grow to higher altitudes. The plant carries either male flowers of female.

Description: Mpapai grows with a naked trunk with a crown of palmate leaves. The trunk can be as thick as 20 cm. The trunk is principally fibre and not very strong. Bark is pale grey and smooth, bumpy where there are old leaf scars. Leaves are up to 60 cm and deeply palmate with hollow 60 cm stalks. Flowers on the male tree are on drooping stalks and a yellow-cream colour and on the female flowers are fewer and beside leaves on the trunk. Waxy petals and cream.Fragrant. Sometimes a male tree will bear fruit and sometimes both sexes are on the same plant. Fruit take about three months to mature round to that of a rugby ball with a thin, green skin ripening to orange. Sweet yellow to orange - almost red flesh inside with many black seeds. A hollow center.

Uses: Fruit, drink, medicine, meat tenderizing [leaves and fruit] removing spines of sea urchins from feet.

Propagation: The seeds are light, 20 000 per kg with viability three years if stored in dry conditions. Take from fruit, clean and dry. Some say that the white seeds are male - not in my experience. Sow direct into pots 3 -5 seeds and germination is 2 -3 weeks. The plant does not tolerate root disturbance. In a plantation 1 male to 50 female is about best. I was never able to tell if a seedling was male or female.

Generally the plant produces well for up to four years, then needs replacing. In the old days orchards were established to harvest the gum but those chemicals seem now to be made synthetically.
Stephen had a grove of special breed Mpapai with large fruit and almost red flesh. I used to buy fruit from him and give the fruit around our village on the expectation that the seed was returned to me.
Many of those plants grew well in the villages but unless the seed was harvested and cross breeding with inferior plants, it is not very likely that such fruit can be found there now.

Psidium guajava

Psidium guajava is the guava tree well known for the canned fruit we have in our Christmas fruit salad, or in Swahili, Mpera. I always get my Swahili vowels mixed up so I might say, Mpera which is a hose!
Psidium guajava origins from South America and is grown for its fruit in India. In Tanzania it is a very useful tree because it tolerates a wide range of conditions but does not like wet feet.
Guava fruits readily and at a young age with vitamin rich fruit. Actually children tend to take unripe fruit - hard and sour and I have no idea of the vitamin content.

Description: A small evergreen tree less than 8 metres high. With no apical dominance. Bark is smooth and light brown with older pieces flaking off. Young shoots are four-sided. Leaves are opposite and oval 15 cm with defined veins. Underside is hairy. Flowers are white 1-3 together, with many stamens. 2 cm across. Fruit yellow when ripe, rounded and 6 cm long the calyx lobes remain on the fruit. The flesh is sweet and gritty with many seeds. Pink when ripe.

Uses: Fruit, soil conservation and shade. The other uses mean the tree will be cut down and that is not ideal but it is goof for firewood, and posts. There are some medicinal uses.

Propagation: There are about 500 000 seeds per Kg although the seeds are hard, they can be direct sowed without and treatment or nicking. Mostly I would sow direct into a pot [2 seeds] and cover with sawdust and some marram to hold it down.
Trees begin to fruit in 2 years with a long lifespan. Throughout the world there are cloned and improved varieties. I preferred the unimproved as it is a stranger tree. The difficulty is finding ripe fruit in private yards is best because they do not utilize the whole crop.
The wood is not eaten by termites.

Guava tends to have a root system that does not allow other crops to grow closely. It is an easy nursery crop and the village people are happy to grow the tree for its fruit.
I thank Fausta who had a very good tree on her property and gave me as much fruit as I needed. The seed is easy to extract and the fruit has a sweet smell.

Syzygium cuminii

Syzygium cuminii or java plumb and the Swahili, Mzambarau is a fruiting tree in Tanzania and kids like the sweet/sour fruit that is inclined to leave the mouth dry. You can always tell when kids have been eating it because their mouths are stained purple.
It is a tropical tree, indigenous to India, Myanmar and the Philippines and will grow in Tanzania to 1000 metres of higher in areas with adequate rainfall.

Description: A large tree up to 30 metres high, with a thick short trunk and large, leafy crown.
Bark is rough and dark but smoother and lighter in the branches. Leaves are opposite, large and oval to 20 cm - smooth and shiny, pointed. Aromatic when crushed. Young leaves are reddish especially the tips. Flowers are green/whitish in clusters below the leaves. Fruit are fleshy and purple when ripe up 2 cm long.

Uses: Food - fruit, tannin, dye, firewood (hopefully from dead fallen branches), timber - especially canoes, shade and soil conservation.

Propagation: There are 500 seeds per Kg and they lose viability very quickly. The seed is 1 cm long and splits in half (not longitudinally as you may expect). Direct sow in a pot, but not covered in soil, just lying on top. Shade to assist in germination. Once germinated it is easy to grow but when out planted needs shade to start off.

I found that eating (or getting people to) the fruit and keeping the seed proves not to be very successful. It is best to find a tree and ask kids to collect germinated seed. Sure plenty are eaten and as is normal when there is abundance, only the best are eaten and the remainder are left to rot. In the shade of the parent tree the seed readily splits with the cotyledons poking upwards and no root radicle showing. Kids easily pick these up and they are easily planted into a pot - job done!
A very useful tree for our work because the fruit is a good source of vitamin C.