American Journal of Plant Sciences, 2010, 1, 131-137
doi:10.4236/ajps.2010.12017 Published Online December 2010 (http://www.SciRP.org/journal/ajps)
131
Rhododendrons in Indian Himalayan Region:
Diversity and Conservation
K. Chandra Sekar1, Sunil Kumar Srivastava2
1G.B. Pant Institute of Himalayan Environment & Development, Kosi, Almora, Uttarakhand, India; 2Botanical Survey of India,
Northern Circle, Dehradun, India.
Received July 23rd, 2010; revised October 27th, 2010; accepted November 2nd, 2010.
ABSTRACT
The genus Rhododendron of Indian Himalayan Region (IHR) has been enumerated in the present paper. A total of 87
species, 12 subspecies and 8 varieties of Rhododendrons recorded in IHR, among these 6 species and one subspecies
are reported from Western Himalaya. The maximum concentration of 86% observed in Arunachal Pradesh (75 species).
The species of Rhododendrons exhibit sig nificant diversity in habit and broad rang e of distribution from the altitude of
800-6000 m. and the best range is observed in 3001-3500 m a ltitudes. In analysis revealed 20 taxa are endemic, 30 are
rare, 24 are threatened / endangered, 3 are vulnerable and 47 taxa have to be assessed. The major threats to rhodo-
dendrons are deforestation and unsustainable extraction for firewood and incense by local people has been discussed.
Keywords: Rhododendrons, Indian Himalayan Region, Ericaceae, India
1. Introduction
The genus Rhododendron, family Ericaceae, was founded
by Linnaeus [1]. The word Rhododendron is derived
from two Greek words rhodon (rose) and dendron (tree)
meaning rose tree. The genus with attractive and beauty-
ful flowers is represented by 850 species in the world [2].
They are mostly distributed at higher elevations in the
Sino-Himalayan region with maximum concentration in
Western China [3]. In India, the species are mostly con-
fined to the Himalayan region, particularly in Eastern
Himalaya. A revision of the genus was carried out by
Cullen [4], Chamberlain [5 ], Philipson and Philipson [6],
Chamberlain and Rae [7], Kron [8] and, Judd and Kron
[9]. Preliminary enumerations and inventories of the ge-
nus were made by Pradhan [3,10], Ghosh and Samaddar
[11], Bhattacharyya and Sanjappa [12]. Sastry and Hajra
[13] and Mao et al. [14] were made the contribution on
rare and endemic Rhododendrons of India. The Rhodo-
dendrons of Sikkim-Himalaya region were done by
Pradhan and Lachungpa [15] and Singh et al. [16]. The
importance of Rhododendrons in Meghalaya dealt by
Yumnam [17].
The Indian Himalayan Region (IHR) occupies a spe-
cial place in the mountain ecosystems of the world. The
IHR is one of the most fragile mountain regions of the
world and holds an enormous repository of biological
diversity which is increasingly under pressure from hu-
man activities. The region comprises a rich variety of
flora, fauna, human communities and culture. Of the es-
timated 8,000 species of vascular plants in the Himalayan
region, around 3,160 are endemic and 450 species are
endangered [18,19]. The indiscriminate exploitation,
destruction of habitats, spread of harmful chemicals and
introduction of alien species, a number of plants have
been disappeared while others await a smilar fate [20].
As a result, gap between demand and supply is widening.
In this regards, global efforts are being made to conserve
the phytodiversity especially rare, endangered and
threatened species, which are known to be important
component of biodiversity.
Due to human interference the natural populations of
rhododendrons in the entire Himalaya are gradually di-
minishing. The major threats to rhododendrons are de-
forestation and unsustainable extraction for firewood and
incense by local people. A set of rhododendrons which
are classified as rare/endangered may be wiped out from
the biota in the near future if proper conservation meas-
ures are not made. So, the present task of diversity and
conservation status of Rhododendrons of Indian Himala-
yan Region has made.
2. Methodology
The present wo rk on Rhododendro ns of Indian Himalay a

Rhododendrons in Indian Himalayan Region: Diversity and Conservation
132
is based on extensiv e literature surveys made in different
states of Indian Himalayan Region (IHR). For the threat
categories, we have consulted different published scien-
tific papers, monographs, red-list documents, IUCN list,
etc. All the taxa have been listed alphabetically with alti-
tude, distribution in Indian Himalayan States and other
region, and revealed threat categories. For enumeration
of species, the IHR is divided into two botanical regions,
namely the Western Himlaya and the Eastern Himalaya.
The Western Himalaya region is the states of Jammu &
Kashmir, Himachal Pradesh and Uttaranchal. Similarly,
the Eastern Himalayan region includes the seven sisters
states of North-Eastern India (Arunachal Pradesh, As-
sam, Manipur, Meghalaya, Mizoram, Nagaland and Tri-
pura), Sikkim and Darjeeling district of West Bengal. The
species of Rhododen drons are calculated and enumerated
in state wise representation of Western and Eastern Hi-
malaya.
3. Results
A total of 87 species, 12 subspecies and 8 varieties of
Rhododendrons r ecorded in IHR (Tab le 1). The Western
Himalaya has 6 species, namely Rhododendron antho-
pogon (Plate 1a), R. arboreum (Plate 1b), R. barba tum, R.
campanulatum (Plate 1c), R. lepidotum and R. nivale;
while Eastern Himalaya is represented by all enumerated
species. The maximum concentration of species is ob-
served in Arunachal Pradesh (86%). Out of 87 species
known from IHR, 75 species occur in the state of Arun-
achal Pradesh alone. The state wise distribution of spe-
cies is showed in Figure 1. The distribution of species in
relation to altitude is shown in Figure 2. The maximum
numbers of Rhododenrons are present in the 3001-3500
m altitudes, lowest in 500-1000 m and above 5000 m,
and absent in less than 500 m (Figure 2). A single spe-
cies namely R. arboreum Sm. is only found in less then
1000 m altitude (from 800 m onwards) and found in al-
most all the states of IHR except Assam and Tripura. R.
nivale H ook. f. is a single species found in abov e 5000m
altitude and found in the state of Sikkim and Uttarakhan d.
The taxa endemic to Arunachal Pradesh are R. arboreum
Sm. subsp. delavayi (Franch.) D. F. Chamb., R. chamae-
thomsonii (Tagg) Cowan & Davidian, R. concin- noides
Hutch. & Kingdon-Ward, R.. falconeri Hook. f. subsp.
eximium (Nattau) D. F. Chamb., R. imberbe Hutch., R.
nayarii G.D. Pal, R. santapaui Sastry, Kataki, P. Cox,
Patricia Cox & P. Hutch. and R. subansiriense D. F.
Chamb. & Cox. The taxa namely R. candelabrum Hook.
f. and R. sikkimense U. C. Pradhan & S. T. Lachungpa
are endemic to Sikkim. R. formosum Kingdon-Ward is
endemic to the states of Arunachal Pradesh and Megha-
laya. A variety, R. triflorum Hook var. bauhiniiflorum
(Watt ex Hutch.) J. Cullen is endemic to Manipur and
categorized as Rare in distribution. R. decipiens Lacait. is
endemic to Sikkim and West Bengal hills. A variety
namely, R. formosum Wall. var. inaequale (Hutch.) J.
Cullen is endemic to Meghalaya, Mizoram and Nagaland.
The species R. johnstoneanum Watt ex Hutch. is endemic
and endangered in Arunachal Pradesh, Manipur and
Mizoram. R. macabeanum Watt ex Balf. f. is endemic
and found in rare in Manipur and Nagaland.
Table 1. Rhododendrons of Indian Himalayan Region.
DISTRIBUTION
S. No. NAME OF THE TAXA ALTITUDE (IN METRE)India Other region STATUS
1 R. anthopogon D. Don 3350-5000 AP, HP, SK, WB Bhutan, China, Nepal, TibetNE
2 R. anthopogon D. Don subsp.
hypenanthum (B alf. f.) J. Cul l en 335 0-5000 AP, HP, JK, SK, UK Bhutan, Nepal NE
3 R. arboreum Sm. 800-3000 AP, HP, JK, UK, MN,
MG, MZ, NG, SK, WBBhutan, Myanmar, Nepal, Sri Lanka, Pakistan, Tibet NE
4 R. arboreum Sm. subsp. Cinnamomeum
(Wall. ex G. Don) Tagg c. 2500 SK, WB Nepal NE
5 R. arboreum Sm. var. roseum Lindl. 2500-3600 SK, WB Bhutan, China, Myanmar NE
6 R. arboreum Sm. subsp.
delavayi (Franch.) D. F. Chamb. 2500-3200 AP, MN, MG China, Myanmar, Thailand NE
7 R. arboreum var. peramoenum (Balf.
f. & Forrest) D.F. Chamb. 3000-3200 AP - EN1
8 R. assamicum Kingdon-Ward c. 3000 AP - EN1
9 R. baileyi Balf. f. 3000-4000 SK Bhutan, Tibet RA1
10 R. barbatum G. Don 2500-3700 AP, SK, UK, WB Bhutan, China, Nep al NE
11 R. beanianum Cowan 3000-3350 AP Myanmar RA1
12 R. boothii Nutt. 1800-2500 AP Bhutan, China TN1
13 R. bulu Hutch. 3000-3800 AP China, Tibet TN1
14 R. calostrotum Balf. f. & King- don-Ward subsp. riparium (King-
don-Ward) J. Cullen 3000-4500 AP China, Myanmar RA1

Rhododendrons in Indian Himalayan Region: Diversity and Conservation
133
Continued Table 1
15 R. camelliaeflorum Hook. f. 2700-4000 AP, SK China, Nepal, Tibet NE
16 R. campanulatum D. Don 2500-4300 AP, HP, JK, SK,
UK, WB Bhutan, Nepal NE
17 R. campanulatum D. Don subsp. aeruginosum (Hook. f.) D. F.
Chamb. 4500-5000 SK Bhutan, Nepal NE
18 R. campanulatum D. Don var.
wallichii Hook. f. 4000 AP, SK Bhutan, Nepal NE
19 R. campylocarpum Hook. f. 3300-4300 AP, SK Bhutan, Myanmar, Nepal,
Tibet RA1
20 R. campylogynum Franch. 2700-4300 AP China, Myanmar NE
21 R. cand elabrum Hook. f. 3600-4300 SK - EN1
22 R. cephalanthum Franch. 3000-4500 AP China, Myanmar RA1
23 R. cerasinum Tagg 3000-3200 AP China, Myanmar, Tibet NE
24 R. chamaethomsonii (Tagg) Co wan &
Davidian 3600-5000 AP - EN1
25 R. ciliatum Hook. f. 2700-3400 SK Bhutan, China, N epal NE
26 R. cinnabar i num Hook. f. 3000-4000 AP Bhut an, China, Nepal, TibetNE
27 R. cinn a b arinum Hook. f. subsp.
xanthocodon (Hutch.) J. Cullen 3000-4000 AP Bhutan, China TN1
28 R. concinnoides Hutch. &
Kingdon-Ward 2400-3400 AP - EN1, TN1
29 R. coxianum Davidian c. 1800 AP - EN1
30 R. crinigerum Franch. 3100-4000 AP China, Myanmar NE
31 R. dal h o u s i a e Hook. f. 1800-2300 AP, SK, WB Bhutan, Nepal NE
32 R. dalho u s i a e Hook. f. var. rhabdotum (Balf. f . & Cooper)
J. Cullen c. 2500 AP Bhutan, China RA1, VU3
33 R. decipiens Lacait. 2500-3000 SK, WB - EN1
34 R. dendricola Hutch. 1200-1400 AP China, Myanmar RA1
35 R. edgeworthii Hook. f. 2100-3300 AP, SK Bhutan, China, M yanmar RA1
36 R. elli ot t ii Watt 2700-3000 MN, NG - EN1, ED1
37 R. eudoxum Balf. f. & Forrest 3300-4000 AP China, Tibet NE
38 R. eudoxum Balf. f. & Forrest subsp.
tamenium (Balf. f. & Forrest) Tagg 3300-4000 AP Bhutan, China NE
39 R. exasperatum Tagg 3000-4000 AP China, Myanmar RA1
40 R. falconeri Hook. f. 2100-4000 AP, SK, WB Bhutan, Nepal NE
41 R. falconeri Hook. f. subsp. eximium
(Nattau) D. F. Chamb. 3000-3500 AP - EN1, ED1
42 R. formosum Kingdon-Ward 1500-2000 MG - EN1, TN1
43 R. formosum Wall. var. inaequale
(Hutch.) J. Cullen 1500-2000 MG, MZ, NG - EN1, TN1
44 R. fulgens Hook. f. 3000-4300 AP, SK, WB Bhutan, China, Ne pal, TibetRA2
45 R. fulvum Balf. f. & W. W. Smi th 2460-3385 AP China, Myanmar, Tibet NE
46 R. glaucophyllum Rehder 3080-3700 SK Bhutan, Nepal, Tibet NE
47 R. glaucophyllum Rehder var.
tubiforme Cowan & Davidian 3100 AP Bhutan, China, Myanmar NE
48 R. grande Wight 2160-3385 AP, SK, WB Bhutan, China, Napel, TibetNE
49 R. griffithianum Wight 2160-2770 AP, SK, WB Bhutan, Napal, Tibet NE
50 R. hodgsonii Hook. f. 3080-36 90 AP, SK,WB Bhutan, Napal, Tibet NE
51 R. hookeri Nutt. 2500-3700 AP Bhutan RA1
52 R. imberbe Hutch. 2770 AP - EN1
53 R. johnstoneanum Watt ex Hutch. 1160-3000 AP, MN, MZ - EN1, ED1
54 R. kasoense Hutch. & Kingdon-Ward 2500-2700 AP China RA1
55 R. kendrickii Nutt. 2300-2800 AP Phutan, China RA1
56 R. keysii Nutt. 2440-3650 AP, SK Bhutan, China, Tibet RA1
57 R. lanatum Hook. f. 3080-4000 AP, SK Bhutan, China, Tibet NE
58 R. lanigerum Tagg 3080-3385 AP China, Tibet NE
59 R. lepidotum Wall. ex D. Don 2160-4620 AP, JK, HP, SK,UK Bhutan, China, Myanmar,
Napal, Pakistan NE
60 R. leptocarpum Nu tt. 2300-4310 AP, SK Bhutan, China, Myanmar,
Tybet ED2
61 R. lindleyi T. Moore 1850-3080 AP, MN, SK,WB Bhutan, China, Myanmar,
Napal, Tibet NE
62 R. macabeanum Watt ex Balf. f. 2500-3000 MN, NG - EN1, RA1
63 R. maddenii Hook. f. subsp. crassum
(Franch.) J. Cullen 2250-3000 MN, MG, NG
Bhutan, China, Myanmar,
Vietnam RA1

Rhododendrons in Indian Himalayan Region: Diversity and Conservation
134
Continued Table 1
64 R. maddenii Hoo k . f. 2400-3650 AP, SK Bhutan, China RA1, ED2
65 R. megacalyx Balf. f. &
Kingdon-Ward 2160-2770 AP China, Myanmar RA1
66 R. megeratum Balf. f. & Forrest 3050-4150 AP China, Myanmar, Tibet RA1
67 R. mekongense Franch. var. rubrolineatum (Balf. f. & Forr.)
J. Cullen 3350-4250 AP China RA1
68 R. nayarii G.D. Pal 2500-3000 AP - NE
69 R. neriiflorum Franch. subsp. phaedropum
(Balf. f. & Farrer) Tagg 3000 AP Bhutan, China, Myanmar TN1
70 R. nivale Hook. f. 4000-6000 SK, UK Butan, China, Ne pal NE
71 R. niveum Hook. f. 3080-3 70 0 AP, SK Bhutan ED2
72 R. nuttallii Booth ex Nutt. 1200-3650 AP Bhutan, China, Myanmar RA1
73 R. obtusum Hort. ex Wats 1500 AP Japan, Myanmar NE
74 R. papillatum Balf. f. & C opper 1800-3300 AP, SK Bhutan, Nepal RA1
75 R. pemakoense Kingdon-Ward 2400-3050 AP China RA1
76 R. pendulum Hook. f. 2270-3650 AP, SK Bhutan, China, Ne pal, TibetRA1
77 R. pocophorum Balf. f. ex Tagg 3650-4600 AP China RA1
78 R. pruniflorum Hutch. &
Kingdon-Ward 3050-3950 AP Myanmar RA1
79 R. pumilum Hook . f. 3500-4500 AP, SK Bhutan, China, Myanmar,
Nepal, Tibet ED2
80 R. rex Levl. subsp. Arizelum
(Balf. f. & Forr.) D. F. Chamb. 3000-4000 AP China, Myanmar RA1
81 R. santapaui Sastry, Kataki,
P. Cox, Patricia Cox & P. Hutch. 2300 AP - EN1, ED1
82 R. setosum D. Don 2160-4950 AP, SK, WB Bhutan, China, Nepal, TibetNE
83 R. sidereum Balf. f. 2770-3080 AP China, Myanmar NE
84 R. sikkimense U. C. Pradhan & S. T.
Lachungpa 3700 SK - EN1
85 R. sinogrande Balf. f. 3080-4310 AP China, Myanmar, Tibet NE
86 R. smithii Nutt. 2160-3700 AP, SK Bhutan, China NE
87 R. stenaulum B a lf. f. & W. W. Smith 2770 AP China NE
88 R. stewartianum Diels 3080-4310 AP China, Myanmar, Tibet NE
89 R. subansiriens e D. F. Chamb. & C o x 2600-2800 AP - EN1, ED1,
VU3
90 R. succothii Davidian 3400-4200 AP Bhutan RA1
91 R. taggianum Hutch. 2160-3390 AP China, Myanmar NE
92 R. tanastylum Balf. f. &
Kingdon-Ward 1850-3350 AP China, Myanmar RA1
93 R. tephropeplum Balf. f. & Farrer 2450-4300 AP China, Myanmar RA1
94 R. thomsonii Hook. f. 3390-4000 AP, NG, SK WB Bhutan, Napal, Tibet NE
95 R. triflorum Hook. f. 2160-2930 AP, SK, WB Bhutan, China, Myanmar,
Nepal, Tibet NE
96 R. triflorum Hook var. bauhiniiflorum (W a tt ex Hutch.)
J. Cullen 2470-3080 MN - EN1, RA1
97 R. tsariense Cowan 2000-3000 AP Bhutan, China NE
98 R. uvarifolium Diels 2160-2470 AP China NE
99 R. vaccinioides Hook. f. 1850-3700 AP, SK, WB Bhutan, Myanmar, Napal,
Tibet NE
100 R. virgatum Hook. f. 2160-2770 AP, SK Bhutan,China, Myanmar NE
101 R. virgatum Hook. f. s ubsp .
oleifolium (Franchet) J. Cullen 2200-3000 AP China, Tibet NE
102 R. veitchianum Hook. 1230-1700 MZ Loas, Myanmar, Thailand RA1
103 R. wallichii Hook. f. 4000-4500 SK, WB Bhutan, China, Nepal NE
104 R. walongense K ingdon-Ward 15 0 0-2150 AP China RA1
105 R. wattii Cowa n 2700 AP, MN - EN1, ED1,
VU3
106 R. wightii Hook. f. 3050-4310 AP, SK Bhutan, China, Myanmar,
Nepal, Tibet RA2
107 R. xanthostephanum Merrill 1500-3000 AP, SK China, Myanmar RA1
1 - Mao et al., 2002; 2 – Singh et al., 2003; 3 - Anonymous, 2009; AP – Arunachal Pradesh; ED - Endangered; EN – Endemic; HP – Himachal Pradesh;
JK-Jammu & Kashmir; MG – Meghalaya; MN – Manipur; MZ- Mizoram; NE – Not Evaluated; NG – Nagaland; RA – Rare; SK – Sikkim; TN-Threatened; UK
– Uttarakhand; VU – Vulnerable; WB – West Bengal

Rhododendrons in Indian Himalayan Region: Diversity and Conservation
135
Name of the States: AP – Arunachal Pradesh; HP – Himachal Pradesh;
JK-Jammu & Kashmir; MG – Meghalaya; MN – Manipur; MZ- Mizoram;
NG – Nagaland; SK – Sikkim; UK – Uttarakhand; WB – West Bengal
Figure 1. Distribution of rhododendrons in different states
of IHR.
Altitudes (in m) A: 500-1000; B: 1000-1500; C: 1500-2000; D: 2000-2500;
E: 2500-3000; F: 3000-3500; G: 3500-4000; H: 4000-4500; I: 4500-5000; J:
>5000
Figure 2. Altitudinal diversity of rhododendrons in IHR.
4. Discussion
The species of Rhododendrons exhibit significant diver-
sity in habit and broad range of distribution from the al-
titude of 800-6000 m. A total of 87 species, 12 subspe-
cies and 8 varieties of Rhododendrons recorded in IHR.
Out of these species, 20 taxa are endemic to IHR. While
considering the status, 47 taxa are not yet evaluated, 30
are rare, 24 are threatened / endangered and 3 are vul-
nerable [14,16,21]. In comparison with neighboring
countries, China is having a total of 571 species of Rho-
dodendrons, out of which 409 species are endemic [22]
and other countries like Pakistan, Bhutan, Nepal, etc are
having very less species diversity in Rhododendrons. A
lot of exploration is still lacking to discover the species
described in other parts of the country, because, the
China and India is having similar habitat in support the
growth of Rhododendrons. While considering the impor-
tance of altitude the maximum number of Rhododen-
drons present in the altitudes of 3001-3500 m. These
altitudes are considered as best suitable sites for Rhodo-
dendrons for conservation and multiplication.
In the recent days, IHR is greatly affected due to vari-
ous threat posed by the nature as well as by human be-
ings. Since Rhododendrons are the inhabitants of the IHR,
they are also greatly affected and their population in the
nature is gradually dwind ling [14]. The rise in population
with demand on land for farming, increased animal hus-
bandry practices, construction of roadways, hydel-power
stations and allied works, army personnel garrisoned at
alpine locations and lately the tourist influx have collec-
tively resulted in the building up of considerable pressu re
on the availability of rhododendron species. The major
threats to rhododendrons are deforestation and unsus-
tainable extraction for firewood and incense by local
people. Due to the presence of polyphenols and flavon-
oids, rhododendrons make excellent firewood that burns
even under wet conditions. Rhododendron firewood is
also being used in the high-altitude trekking corridor for
the purpose of tourism. Some of th e species have already
become scarce, for example, R. leptocarpum is endan-
gered and reported to have only 16 surviving individuals
at present in the Sikkim [16].
The conservation of Rhododendron species can be ef-
fected by two well established means, the in-situ and ex-
situ methods. In-situ conservation can be brought about
by establishing Rhododendron sanctuaries, Parks, etc.
Some efforts by Sikkim forest department and Sikkim
Rhododendron Society have been made by fencing the
Rhododendron rich sites and declaring them as Rhodo-
dendron Sanctuary between Lachung and Yumthang in
the State. Similar efforts need to be made by Arunachal
Pradesh Government as the state is home for more than
50 percent rare and endemic IHR species. The ex-situ
conservation can be effected by cultivating Rhododen-
dron species in the gardens and parks under suitable cli-
matic conditions or by using tissue culture techniques.
There should not be many difficulties in introducing
these species in Botanic Gardens and Parks as most of
them have successfully b een introduced and cultivated in
the European and American countries. The species of
Rhododendron arboreu m are prop ag ated thro ugh cu ttings
[23,24]. Tissue culture studies of Indian Rhododendrons
are recently initiated; only few species especially Rho-
dodendron maddeni has only been propagated through
tissue culture methods (Singh and Gurung, 2009) and
some others are under progress. But in for eign countries,
the Rhododendrons have already been carried out for
commercial cultivation [26-32]. The standard culture
medium for tissue culture methods is read ily available in
the market [14]. Successful tissue culture of these species
will be a great contribution for rapid multiplication and

Rhododendrons in Indian Himalayan Region: Diversity and Conservation
136
towards in-vitro conservation. The success of conserva-
tion programme depends on the awareness of local peo-
ple. It is imperative to educate the local inhabitants abou t
the wealth of Rhododendrons and importance towards
the conservation of biodiversity in IHR.
5. Acknowledgements
The authors are thankful to Dr. L.M.S. Palni, Director,
G.B. Pant Institute of Himalayan Environment & Devel-
opment, Kosi-Katarmal, Almora for providing facilities
and encouragements. Sincere thanks to Drs. S.K. Nandi,
Scientist—F & Group Head—BCM & BTA Group and
Dr. R.S. Rawal, Scientist—E, BCM Theme, G.B. Pant
Institute of Himalayan Environment & Development,
Kosi—Katarmal, Almora for constant support. We also
grateful to Dr. Debjyoti Bhattacharyya, Assam Univer-
sity, Silchar for valuable comments and suggestions.
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