Model ecological restoration of submontane forest in Kenya

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1 Model ecological restoration of submontane forest in Kenya Brackenhurst Botanic Garden Tigoni, Kenya Mark Nicholson, DTVM, Ph.D. (Cambridge)

2 Ecological restoration in practice The context in Kenya Principles of restoration in relation to FLR The process on site Environmental education A forest in more than trees: trophic levels

3 The context Threats to biodiversity and ecosystems in Kenya

4 Rate of total destruction (land use change) >> rate of restoration

6 Very poor security; collusion with forest officials.

8 Threats: Degradation (irrecoverable in the short term)

10 Threats: land use change, smallholder agriculture; urbanization, plantation crops

Tea country (1800-2000m): plantations of wattle, eucalyptus, Grevillea;

12 Tea country ( m): plantations of wattle, eucalyptus, Grevillea; windbreaks of Hakea; scattered indigenous trees. Valleys dry for 6 months a year.

13 Collecting sites Loima Marsabit Mt. Kulal Ndotos Matthews Kakamega Cherangani Aberdares Mt. Kenya Nairobi Mara/ Loita/ Nguruman Chyulu Hills Kilimanjaro (Kenya) Kitui (Mutha/ Endau) Taita hills/ Kasigau

14 Brackenhurst forest Altitude: m; +1200mm rainfall Ecologically degraded area, now reverting to a natural submontane forest ecosystem 110,000 woody native plants grown (5 year survival rate is 90%). NO natural regeneration Also collect from dryland, rainforest (from W. Kenya), woodland and grassland species all ex situ and many disappearing naturally 1500 plant species (>500 woody species of trees, shrubs & climbers; >140 families)

15 Sources of taxa

16 Cassine schlechteranum

18 Ex situ conservation

19 Cylicomorpha parviflora Ex situ conservation Ex situ conservation: Widdrintonia whytei & W. cedarbergensis

21 2000: 99% exotic species Note this tree (Pouteria adolfifriedericii) Black wattle Eucalyptus Cypress

Brackenhurst Botanic Garden in 2017 Ecological restoration project 2000-2030

22 Brackenhurst Botanic Garden in 2017 Ecological restoration project (99% indigenous) Same tree 17 years later Our aim: to recreate a natural forest

23 2010 from Government land: note cattle and wetland barrier

24 General restoration principles 1. Restoring is not restoration: Bonn challenge mentions 150m ha RESTORED by 2020, and 350 m ha by e.g. Kenya target is 5m ha. Ethiopia will have RESTORED 15m ha by International/ national commitments are necessary but should be realistic and achievable. 4. Have the indicators of restoration been spelled out? Restoration is NOT about numbers of trees planted. 5. Dryland reforestation is much more challenging because of vicissitudes of climate. 6. Two types of forest restoration: a) Enrichment (active or passive), OR b) Land use change back to original ecosystem (TOTAL & ACTIVE restoration. Most projects are about enrichment 7. Livestock (wildlife?) are major handicaps in successful restoration. 8. A forest is more than trees

25 Native forest restoration 1. Is FLR about native forest restoration or land restoration?? If it is land restoration, what is the endpoint? 2. Is it ignoring the rangelands and GRASS? The major causes of rangeland degradation are overgrazing and gradual removal of woodland species. 3. Total forest restoration takes TIME & MONEY. We set a target of 30 years ( ) for restoring a 40 ha patch of forest. 4. A block of one or two species of indigenous tree may be a forest but is NOT ecological restoration 5. Our project is the creation of a natural forest is this an oxymoron? 6. FLR, as we interpret it, should be ecological restoration of: - NATIVE plant and animal biodiversity - trophic levels - ecosystem services - edaphic factors: S.O.M., fertility, structure, water infiltration rates 7. Know your biodiversity, because you cannot restore if you don t 8. In our forest we set a goal of >250 identified plant species per 2ha. block (>50 spp. of trees), inclu. herbs, Poaceae, Pteridophyta, Bryophyta etc

26 Calanthe sylvatica Eulophia stenophylla

27 Oplismenus hirtellus Oplismenus undulatifolius

28 Euphorbia prostrata

31 Low biodiversity

32 Total restoration The process

33 NO regeneration of native trees as the area had been a gum. Cypress or wattle forest for > 60 years

34 In 2000, Brackenhurst had <20 indigenous trees but a nearby forest has about 50 woody species. Common species include: Araliaceae: Polyscias kikuyensis Clusiaceae: Garcinia volkensii Euphorbiaceae: Croton megalocarpus/ C. macrostachyus Euphorbiaceae Macaranga kilimandscharica Lauraceae: Ocotea keniensis (O. usambarensis extirpated?) Malvaceae: Cola greenwayi Meliaceae: Ekebergia capensis Moraceae: Ficus thonningii Olacaceae: Strombosia scheffleri Phyllanthaceae Margaritaria discoidea Rosaceae: Prunus africana Rubiaceae: Psychotria mahonii/ P. fractinervata Rutaceae: Zanthoxylum gillettii / Clausena anisata Rutaceae Vepris simplicifolia Salicaceae: Casaeria battiscombei Sapotaceae: Pouteria adolfi-friedericii

35 Why we prefer scientific names Croton megalocarpus Eng: none Luhya: Musine Boran: Napo Kikuyu: Mukinduri Maa: Olmergoit Tugen: Ortuet Samburu: Lameruguet Kamba: Muthulu/ Kithulu Pokot: Korelach Nandi: Masineitet Taita: Mukigara Gabbra: Nyaap po Luganda: Nkulumire Buddu: Mbula Rukiga: Mutakura Rutoro: Munyabakuru Runyankore: Mutagunda

39 Note grass, woodland spp. (acacia [S. xanthophloea])

40 15 years later Reforestation under former cypress: no regrowth, no invasives, easy to restore if understory plants proactively planted

42 Replanting on land formerly under gum & wattle very difficult

44 Former gum plantation: no active understory planting but invasives cleared. Trees fine, light shade.

46 Basella alba

47 60 years under wattle: S.O.M. >2-3% 17 years under indigenous forest; S.O.M. just below leaf litter layer + 24%

48 Environmental education Three main targets: The Youth Women Professionals

50 Environmental education: Global initiative service Summit: visit to Brackenhurst Feb 23 rd 2013

52 Lack of knowledge of plant identification, ecology & taxonomy In 2017 we had a training course on ecological restoration: 29 attendees from 2 govt. institutions and 7 NGOs. We quizzed them on 25 less common species asking for Family, Genus, Species & vernacular name (Max. 100 marks) Median score 7/100 (one person got 34) N.B. Regional training course in 2017/18 on plant identification

53 Loss of indigenous knowledge leads to loss of indigenous biodiversity Which of the following 6 simple, lobed leaves is ecologically the odd one out?

55 X Obetia radula Cola gigantea Ficus exasperata Macaranga schweinfurthii Cylicomorpha parviflora

56 V. simplicifolia V. eugenifolia (R) V. trichocarpa V. fadenii (very rare) V. nobilis V. glandulosa (rare local endemic)

A new species of Prunus (Rosaceae) from Kakamega Forest in western Kenya Mark Nicholson 1, Roy E. Gereau 2, and Heidi H. Schmidt 2 1 Brackenhurst Botanic Garden, P.O.

) Kalkman has been generally recognized as the only native species of Prunus on the African continent, with a second named species, P.

A Prunus species found in Kakamega Forest differs from P. africana in several morphological characters. About 250 seedlings have been distributed to other gardens and forests.

Flowering and fruiting material was collected from the cultivated individuals in 2011 and compared with published descriptions and herbarium specimens to determine its taxonomic status. Prunus sp.

57 A new species of Prunus (Rosaceae) from Kakamega Forest in western Kenya Mark Nicholson 1, Roy E. Gereau 2, and Heidi H. Schmidt 2 1 Brackenhurst Botanic Garden, P.O. Box 617, Limuru 00217, KENYA, 2 Missouri Botanical Garden, P.O. Box 299, St. Louis, MO , U.S.A. Background Prunus africana (Hook. f.) Kalkman has been generally recognized as the only native species of Prunus on the African continent, with a second named species, P. crassifolia (Hauman) Kalkman, accepted in some sources (Hauman, 1952) but often considered only an extreme form in leaf fleshiness of P. africana (Graham, 1960; African Plant Database, 2017). A Prunus species found in Kakamega Forest differs from P. africana in several morphological characters. About 250 seedlings have been distributed to other gardens and forests. Methods In 2006 seed was collected from a tree ca. 20 m high in Kakamega Forest and propagated in Brackenhurst Botanic Garden. Flowering and fruiting material was collected from the cultivated individuals in 2011 and compared with published descriptions and herbarium specimens to determine its taxonomic status. Prunus sp. Prunus sp. Flora of Tropical East Africa (Graham, 1960) & Flora Zambesiaca (Mendes, 1978) Flora of North America (Rohrer, 2014) & McVaugh (1951) Prunus africana (Hook. f.) Kalkman Prunus serotina Ehrh. Prunus sp. Specimen data from Nicholson Leaves: Size 4-15 x cm x cm x cm Shape lanceolate, lanceolate-elliptic, elliptic-oblong, ovate, obovate, lanceolate, lanceolate-elliptic, elliptic-oblong, ovate, obovate, lance-ovate Data from MO herbarium African specimens and literature length : width ratio Color (abaxial vs. adaxial) discolorous or not discolorous not discolorous Sheen matt or shiny matt or shiny v. glossy surface Pubescence glabrous glabrous or densely pubescent along midrib abaxially Base shortly cuneate, rounded cuneate, rounded rounded Apex obtuse, acute, acuminate, long-acuminate acute, acuminate [curled] acute, acuminate Margin crenulate, serrate crenulate, serrulate [serrate] serrate, serrulate Lateral veins not distinct or distinct not distinct distinct Petiole cm cm, dull red cm, green ovate glabrous or with tufts of pubescence in vein axils abaxially Prunus serotina Prunus sp. Prunus sp. Kakamega Forest is a tropical rainforest situated in the Kakamega and Kisumu counties of Kenya, northwest of the capital Nairobi, and near to the border with Uganda. It abuts the eastern side of Kakamega town in Western Province of Kenya. The forest is located between 0 08 N to 0 22 N and E to E. The forest lies in Lake Victoria Basin, about 150 km west of the Great African Rift Valley, from which it is separated by highlands stretching from Cheranganis in the North to the Mau Escarpment in the South. To the East it borders North Nandi forest atop the Nandi Escarpment (at over 2200 m), while it borders South Nandi forest towards the South-east. Kakamega Forest is Kenya's only tropical rainforest and is generally considered the eastern-most remnant of the lowland Congolean rainforest of Central Africa. It is dominated by central African lowland species, but due to its elevation (predominantly between m) and proximity to the formerly contiguous Nandi Forests it also contains highland elements. The forest including reserves encloses about 238 square kilometers, a little less than half of which currently remains as indigenous forest. The Kakamega Forest is very wet, with an average of mm of rain per year. Rainfall is heaviest in April and May ("long rains"), with a slightly drier June and a second peak roughly in August to September ("short Results The inflorescences and fruit of the Prunus species from Kakamega are distinctly different from Prunus africana and resemble the New World P. serotina Ehrh., but the latter species has black rather than red fruit when ripe. The flowers of P. africana are borne in shorter and less dense racemes than those of the Kakamega tree, and the fruits of P. africana are oblate (wider than long), while those of the Kakamega tree are spherical. Furthermore, the leaf blades of P. africana are consistently shorter and narrower than those of the Kakamega tree, and the petiole of P. africana is shorter. Conclusion Several morphological characters of the Kakamega Prunus fall outside the known range of Prunus africana. Pending final investigation we suggest that it may represent a new species to science. All photos courtesy of Mark Nicholson Literature Cited African Plant Database (version 3.4.0). (2017). Conservatoire et Jardin botaniques de la Ville de Genève and South African National Biodiversity Institute, Pretoria, retrieved April 2017 from / Graham, R.A. (1960). Rosaceae. In: C.E. Hubbard & E. Milne-Redhead (editors), Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London. Hauman, L. (1952). Rosaceae. In: Comité exécutif de la Flore du Congo belge et le Jardin Botanique de l État, Flore du Congo Belge et du Ruanda-Urundi 3: I.N.É.A.C., Brussels. McVaugh, R. (1951). A revision of the North American black cherries (Prunus serotina Ehrh., and relatives). Brittonia 7: Mendes, E.J. (1978). Rosaceae. In: E. Launert, J.P.M. Brenan, A. Fernandes, & H. Wild (editors), Flora Zambesiaca 4: Flora Zambesiaca Managing Committee, London. Rohrer, J.R. (2014). Prunus. In: Flora of North America Editorial Committee (editors), Flora of North America 9: Oxford University Press, New York.

58 Monitoring tree growth 5000 trees planted in 2012: 50 species in 4 plots. (Repeated in 2013 using three replicates). We measure dbh, height and canopy width. 3 arbitrary categories of growth rates: 1. Rapid >1.5 m/yr (Olea welwitschii, Milletia dura, Vitex keniensis, Rauvolfia caffra, Polyscias spp.) 2. Medium m/yr (Prunus, Sapotaceae) 3. Slow <0.5m/yr (Gardenia,Garcinia/ Strombosia): some as slow as 10 cm/yr.

60 Top performing tree species Height (cm) at 5 years; n=10 per species; x (cm) + S.E.) 1. Millettia dura 2. Trema orientalis 3. Polyscias kikuyuensis 4. Vitex keniensis 5. Dombeya torrida 6. Rauvolfia caffra 7. Hagenia abyssinica 8. Erythrina abyssinica

61 Top performing tree species 5 year dbh ([cm]; n=10 per species; x + S.E) 1. Hagenia abyssinica 2. Dombeya torrida 3.Trema orientalis 4. Polyscias kik./ P. ful 5. Rauvolffia caffra 6. Erythrina abyssinica 7. Vitex keniensis 8. Millettia dura

62 What is the fastest growing species? Winner on height Winner on dbh 1. Millettia dura 2. Trema orientalis 3. Polyscias kikuyuensis 4. Vitex keniensis 5. Dombeya torrida 6. Rauvollfia caffra 7. Hagenia abyssinica 8. Erythrina abyssinica 1. Hagenia abyssinica 2. Dombeya torrida 3.Trema orientalis 4. Polyscias kik./ P. ful 5. Rauvolffia caffra 6. Erythrina abyssinica 7. Vitex keniensis 8. Millettia dura

63 Which is the fastest growing species? None of the above! cm (5 yrs) m (23 yrs) Olea welwitschii (n=4) Croton macrostachyus (n=1) (cf. Millettia dura 480) So why didn t we measure O. welwitschii or Croton?? Olea ALL eaten. Croton does not like wind so we did not plant it on the hill

64 Antelope damage: Vangueria resprouting from base

65 What can we can conclude from these data? 1. It excludes trees that were eaten by antelope (100% of Olea welwitschii, Bridelia micrantha etc were eaten) 2. No replicates in first trial. In sheltered damper area, trees will grow faster than this. 3. We planted what we had. 4. These trees were planted in a grass field. In a real forest, seedlings are competing and many other spp. may be there e.g. Sapots, Diospyros, Prunus, Ocotea, Nuxia, Anthocleista etc. 5. So are we just measuring pioneers? 6. Croton macrostachyus is a woodland sp., not a forest sp. Nor, arguably, is Hagenia.

66 Greater Galago White-tailed Mongoose, Black-tipped mongoose, Genet Cat, Civet Cat, African Clawless Otter, African Palm Civet, Black-backed Jackal, African hedgehog, Grey Duiker, Black & White Colobus, Sykes Monkey, Bush Pig, Porcupine, Fruit & insectivorous Bats

67 Chrysomelidae: leaf miner; larva lives on Neoboutonia Trophic levels 2 & 3 Heteracris brevipennis Coccinellidae

68 Colobus gureza. Left the site in 1939, returned naturally 2015

69 A forest is more than trees (Trophic level 2)

72 Atelerix albiventris: trophic level 3

73 A forest is more than trees Kikuyu Three-horned Chameleon (Chamaeleo jacksoni)

74 Von Hoehnel s chameleon (Chameleo hoehnelii)

75 What do bats pollinate? What pollinators are we missing?

76 Trophic level 4: the predators that eat the hedgehogs & bushbabies

77 project that aspires to influence NGO and parastatal reforestation initiatives.

78 Thanks for listening! Acknowledgements: We are grateful for the support of BGCI, Ashden Trust and Idaho Botanical Institute

Common Name: AMERICAN BARBERRY. Scientific Name: Berberis canadensis Miller. Other Commonly Used Names: none. Previously Used Scientific Names: none

Common Name: AMERICAN BARBERRY Scientific Name: Berberis canadensis Miller Other Commonly Used Names: none Previously Used Scientific Names: none Family: Berberidaceae (barberry) Rarity Ranks: G3/S1 State