The vegetation in the lower slopes of Mount Kenya, is of a mountains rain forest. That forest is prominent in the tallness of some of the trees that grow in it. Those trees include the African Wild Olive (Olea europaea subsp. cuspidata), and also Ocotea,which is also called: Camphor. That tree, can reach a tallness of about 40 m, while the diameter of its trunk that can reach 3 m [3]. The vegetation belt of that mountains rain forest, is not noticed, when we climb to Mount Kenya from its western side, through the Naro-Moru hiking trail. The Naro-Moru hiking trail, starts at the Naro-Moru village, which is located west of Mount Kenya. Afterwards that trail enters Mount Kenya, at the main gate of the Mount Kenya Nature Reserve, in a height of about 2400 m ASL (Figure 1) [4] (p. 55).

Figure 1. A view to Mount Kenya from the entrance to the Mount Kenya Nature Reserve.

Above the mountains rain forest, grows in Mount Kenya, a coniferous forest, which is dominated by Podocarpus trees (Figure 2). It seems that those Podocarpus trees are of: Podocarpusmilanjianus. The vegetation belt of the Podocarpus forest in Mount Kenya, ranges mainly between heights of 2000 m - 2500 m ASL. Some of those Podocarpustrees, serve also as habitats to lichens of the genus: Usnea (Figure 3). The Usnealichens which grow in Mount Kenya, are usually of: Usnea longissima, which is also called: Bearded Lichen. The following other trees that grow in that forest, are: Cyathea, Juniperus, and also a wild Banana tree: Ensekverticosum [4] (pp. 55-56).

When I toured to Mount Kenya, in August 1983, I also, took a photo of Eupatoriumshrub of the Asteraceae (Figure 4). According to some internet sources, Eupatorium plant, is not known from Mount Kenya. Therefore, the documentation, that I bring here in Figure 4, can be recognized, as a noteworthy field observation from August 1983, which warrants further investigation through new surveys or herbarium research in the future. It is also possible, that Eupatorium shrubs grew in Mount Kenya in the year of 1983, but later maybe because of climate change consequences, became rare plants in that region.

Figure 2.Podocarpus trees near the Naro-Moru trail in elevation of about 2400 m ASL.

Figure 3. Lichens of the genus: Usnea, grow on Podocarpus trees.

Figure 4.Eupatoriumshrub in thePodocarpusforest.

In the sub-forest of that vegetation belt, can also be found several kinds of Bryophytes (Figure 5), ferns, and also Lycopodiaceae plants (Figure 6, Figure 7). According to some internet sources, in Mount Kenya grow also 194 identified species of Bryophytes. The Lycopodiaceae plants, which appear inFigure 6, Figure 7, look like: Lycopodiumclavatum, which is a common Lycopodial plant that grows in the moist mountain forests of Mount Kenya.

Figure 5. Bryophytes, in the sub-forest of the Podocarpus plant society.

Figure 6. Close look at Lycopodiaceae plants, in the sub-forest of the Podocarpus plant society.

Figure 7.Lycopodiaceae plants, in the sub-forest of the Podocarpus plant society.

Figure 8. A Butterfly flower—Impatienshoehnelii,in the Podocarpusforest.

A Butterfly flower (Impatienshoehnelii) (Figure 8), of the Balsams plant group (Balsaminaceae). That plant is considered as an East African plant, found mainly in the mountain forests of Mount Kenya.

Figure 9.Kniphofiathomsonii,in the sub-forest of the Podocarpus plant society.

The plant which appears in Figure 9, looks like:Kniphofiathomsonii of the Asphodelaceae (Figure 9). That plant is called also: Thomson’s Red-hot Poker, or; Alpine Poker. The distribution of that plant includes several regions in East Africa (https://www.wikipedia.org/; https://www.inaturalist.org/).

The Bamboo area, is also common in Mount Kenya, in heights of between 2200 m - 2600 m ASL. The Bamboo plants in that region, grow in a plant formation which also looks like a forest, although those Bamboo plants are perennial grasses. The Bamboo plants in Mount Kenya, are of the genus: Arundinaria, possibly of: Arundinariaalpina, which usually grow, to a tallness of about 10 m - 20 m [3]. Some of those Bamboo plants can even reach tallness of up to 40 m [4], p. 56-57. Since the Bamboo forest in Mount Kenya is quite dense, that seems to prevent other species of plants to grow in that vegetation belt [4] (pp. 56-57) (Figure 10).

Figure 10. In the bamboo forest.

Above the Bamboo vegetation belt, grows in Mount Kenya, a forest of Hagenia (Rosewood) trees, of the Rosaceae. The vegetation belt of the Hagenia forest in Mount Kenya, ranges between 2600 m - 3000 m ASL. Some of those Hagenia trees are of an age of hundreds of years [3]. The Hagenia trees in Mount Kenya are mainly of: Hageniaabyssinica (African redwood) (inaturalist.org).

At some locations in that Hagenia forest, there also grows: Hypericumkeniensis orHypericumrevolutum [4] (p. 57). Hypericum in Mediterranean regions usually appear as sub-shrubs. However, the finding that Hypericum plants in the Hagenia forest in Mount Kenya, grow to such big dimensions, is also another evidence, to the phenomenon of gigantism of plants in African high mountains [4] (p. 57).

In the sub-forest of that Hagenia plant society, grow several more plants, which include also the following perennial plants. Red Gladiolus, which is also identified as: Gladioluswatsonioides, of the Iridaceae (Figure 11). A subshrub of the genus: Helichrysumof the Asteraceae (Figure 12). That Helichrysum, does not look like: Helichrysumbrownei, which grow in Mount Kenya in its Afro-Alpine vegetation belt.

Figure 11. Red Gladiolus—Gladioluswatsonioides, in the Hagenia forest.

Figure 12.Helichrysum, in the Hagenia forest.

The forest line is also defined, as the upper limit of the areas, where trees grow in high mountains. Close to the forest line of Mount Kenya, is also located the Meteorological Station Camp, in height of about 3050 m ASL. That hiking camp is used by travelers to spend the night between the 1^st day of their hike, to the 2d day of their hike, when they climb from the entrance to the Mount Kenya National Park, to any of the summits of that mountain. The forest line in Mount Kenya is also located in elevations of between 3000 m - 3500 m ASL (Figure 13).

Figure 13. In the forest limit of Mount Kenya, at elevation, of about 3400 m ASL.

Figure 14. Flowers, of an Erica shrub in Mount Kenya.

The vegetation, right above the forest line of Mount Kenya, is also of Erica shrubs. Ericashrubs are common in high mountains, also in other regions of the world, and they are known, as occupying the upper side of forest lines in several regions of the world. In Mount Kenya, Erica shrubs grow mainly in elevations of 3200 m - 3500 m ASL. The Ericaplant, that I photographed in Mount Kenya in August 1983, was from a lower elevation within the Mount Kenya Nature Reserve (Figure 14).

The Afro-Alpine zone in Mount Kenya starts, in an elevation, of about 3500 m ASL. From that elevation, towards the area below the summits of Mount Kenya, the landscape, is also, of a continuous moderate slope which leads us from that elevation up to Mackinders Camp, at an elevation of about 4200 m ASL. That area, receives high amount of rain water. Therefore, the soil in that slope is muddy. The vegetation, in that area, is defined as moorland (Figure 15).

In the lower part of that Afro-Alpine moorland, grow also the following 2 species of Lobelias. The Teleki Lobelia (Lobeliatelekii), which its flowers look like feathers of an Ostrich. Mount Kenya Lobelia, which is also called: The Giant Lobelia (Lobeliagregoriana), which its flowers are purple. That species of Lobelia was formerly called: Lobeliadeckenii subsp. Keniensis (Figure 16). The flowers of L.gregoriana, are pollinated by hummingbirds called: Johnston Hummingbirds, which can reach heights of about 4000 m ASL [3].

Figure 15. Landscape of moorland, at a height of about 3600 m ASL.

Figure 16. Plants of Lobelia, in a height of about 3600 m ASL.

The Lobelias in Mount Kenya, demonstrate also the phenomenon of gigantism of some plants, at high elevations, in African mountains. Lobelias in that vegetation belt in Mount Kenya, can reach tallness of up to 4 m [3]. Researches raised a hypothesis, that when those Lobelia plants are farther from the ground, they receive less amount of coldness at night, because most of that coldness comes from the ground. Additionally, some researchers found in some tissues of leaves’ rosettes of Lobeliatelekii plants, in Mount Kenya, an anti-freeze chemical, which also protects the buds of those plants [5]. The buds of those plants need protection from freezing temperatures. It was also found, that in: Lobeliagregoriana, those buds are coated by envelopes of hundreds of leaves, which close at night, and also open during daytime. Those leaves isolate those buds, and therefore protect them against the coldness of the night [6].

In a height of about 3600 m ASL, I documented in August 1983, a subshrub of the Asteraceae (Figure 17).

In Mount Kenya, the elevations of between 3500 m - 3800 m ASL, are also characterized by: high rainfall, thick humus layer, high tussock grass moorland, low species richness. The elevations of between 3800 m - 4400 m ASL, in Mount Kenya, are also characterized by more scattered vegetation, which also includes Giant Senecio plants.

Figure 17. A bush of the Asteraceae, at a height of about 3600 m ASL.

The Giant Senecio of Mount Kenya, is also called: Giant Groundsel (Dendroseneciokeniodendron). Since those Senecio plants are typical to the higher elevations of Mount Kenya, I think we can call those plants: Mount Kenya Senecios. In the lower part of the high alpine zone, of Mount Kenya, can be also found Lobelia plants together with Mount Kenya Senecio plants in the same area (Figure 18). That area looks like, a transition area between the area of the Lobelia plant society from its lower side, and also the Mount Kenya Senecio plant society, from its upper side.

Figure 18. A field of Lobelias, together with also Senecios.

Some of those Senecios reach, to a tallness of about 8 m, although the Mount Kenya Senecio is a perennial grass [3] (Figure 19). The Mount Kenya Senecios develop flowers once in 20 - 30 years, a phenomenon which is also not understood yet. When those plants flower, they develop an inflorescence column, which can also reach an additional tallness of 2 m [3]. The Mount Kenya Senecios also demonstrate the phenomenon of gigantism of some plants in African high mountains. That phenomenon of gigantism of some plants is considered to be also, an adaptation to the coldness in some African high mountains. In the region of Mount Kenya, the temperature becomes cooler by 1˚C when increasing the height by 150 m. The diurnal temperature differences in Mount Kenya, are also relatively large [1][3]. The Mount Kenya Senecios, have also, an additional adaptation to coldness, by an antifreeze substance in their leaves, possibly similar to the same mechanism, that was found in Lobeliatelekii plants in Mount Kenya [5][6].

Figure 19. Mount Kenya Senecios, above Teleki Valley.

After the 2d day of our tour to Mount Kenya, we reach Mackinders Camp, in elevation, of about 4200 m ASL. The vegetation in Mackinders Camp is a typical Afro-Alpine grassland, which includes also many Mount Kenya Senecio plants (Figure 20).

Figure 20. Mackinders Camp, at a height of about 4200 m ASL.

From elevations, of about 4200 m ASL upwards, the vegetation becomes more dilute, until it reaches in elevations, of about 4600 m ASL, the so-called: Nival area, which is also called: The Alpine area. The Alpine area, is an area which almost, does not include vegetation in it. The Alpine area in Mount Kenya ranges from about 4600 m ASL, up to the summits of that mountain [1][3].

The 3’d day of the hike to Mount Kenya, is from Mackinders Camp, to the area of the peaks of Mount Kenya, in elevations, of around 5000 m ASL. A description of the route from Mackinders Camp to that summit area I would like also to bring, in a separate article.