The plant world of the reserve

Flora

Around 800 plant species are recorded for Nilo, including several Saintpaulia taxa, the wild relatives of the African violet. The elevational zonation of the forest from the boundary to Nilo Peak at 1,506 m has not been documented in recent years.

Vegetation by elevation

Four belts, undocumented at Nilo

Rainfall, temperature and mist change with elevation, and the forest changes with them. In the East Usambaras the sequence below is typical. Where the belts lie at Nilo, and how sharply they separate, is one of the open questions for a placement.

Upper submontane · ridge

Ridge and mossy forest

Cool, cloud-fed forest on the highest ground; trunks and branches thick with moss, ferns and epiphytic orchids.

Submontane · core belt

Submontane rainforest

The heart of the reserve: tall evergreen forest with camphorwood and other hardwoods.

Transitional

Mid-elevation forest

A rich transitional band where lowland and montane species overlap.

Lowland

Foothill and lowland forest

Warm, humid forest at the base of the range, most exposed to clearing and fire.

Signature plants

Plants of the East Usambaras

Species and groups typical of these forests. Apart from Saintpaulia, which is documented for Nilo, presence and abundance at Nilo are to be confirmed.

African violet

Streptocarpus ionanthus (Saintpaulia)

The wild relative of the world's best-known houseplant grows on shaded rock faces in these mountains. Several taxa are recorded for Nilo.

Usambara originRecorded at Nilo

East African camphorwood

Ocotea usambarensis

A giant of the submontane forest and a prized timber, which is why it is a main target of illegal logging.

Eastern Arc endemicTargeted by logging

Tree fern, Cyathea, along a shaded stream in East Usambara forest, Tanzania

Tree ferns

Cyathea spp.

Along shaded streams and moist ravines, tree ferns give the forest its primeval character.

StreamsAncient lineage

Epiphytic orchid in the canopy of an East Usambara forest, Tanzania

Epiphytic orchids

Orchidaceae, various

The humid canopy hosts a wealth of epiphytic orchids, a useful indicator group for forest integrity.

EpiphyticHigh diversity

Forest balsam, Impatiens, in the understorey of an East Usambara forest, Tanzania

Forest balsams

Impatiens spp.

Delicate herbs of the shaded understorey, with many local forms across the Eastern Arc.

Eastern Arc formsUnderstorey

Allanblackia

Allanblackia stuhlmannii

A tall canopy tree bearing large seed pods rich in edible fat.

Eastern Arc endemicCanopy tree

For a thesis or placement project

Research questions and open topics

Mapping and micro-habitat of Saintpaulia populations at Nilo: rock faces, shade, moisture, distance to the boundary.
Regeneration of Ocotea usambarensis after selective logging: seedling and sapling densities in logged and unlogged plots.
Elevational zonation of the vegetation from the reserve boundary to Nilo Peak, using a series of plots along a transect.
Epiphyte and orchid diversity as an indicator of forest integrity, compared between edge and interior.
Invasive and pioneer species along the boundary and in gaps, and their spread into the reserve.

None of these questions has been worked on at Nilo in recent years. A placement student can take one of them as the core of a thesis project, or propose another one.

Field placement at Nilo Forest

Currently sought: students for field placements

Field placement at Nilo Forest

Three to six months at the reserve boundary, own project, data for your thesis. Start possible now, rolling intake.

Read the details Apply by e-mail