3.2.4 Additional Data
This section provides information on each of the identified additional variables. It contains
relevant definitions, source and source data, temporal trends and its assessment.
3.2.4.1 Status of Natural Regeneration
Natural regeneration indicates the capacity of ecosystem to sustain the “forests” in perpetuity.
The information was collected by FSI while conducting forest inventories. FAI follows a
systematic sampling method for its forest inventories where it overlays a 2 ½’x 2 ½’ grid of
latitudes and longitudes divides on a 1:50,000 scale topographic sheet to divide it into 36 grid
cells and selects two sample points within each such grid for collecting inventory data from a
67 (114)
square plot of 0.1 ha at each of these sample points. The FSI lays a 4 m x 4 m plot at each of two
sample points to collect supplementary data on natural regeneration.
Definition (FAOA)
No standard national definition is available
Terms Definition
Natural Regeneration
Natural succession of forest trees on temporarily unstocked forest lands
Transformation There is no need for transformation of the variable.
Data and Temporal Changes
The information on assessment of regeneration is only available for only 1982 and 1992.
Trend in Percentage of Forest Lands with
Natural Regeneration
61.5
26.4
0
10
20
30
40
50
60
70
1980
1985
1990
1995
2000
2005
Year
Pe
rc
e
n
ta
ge
of
N
a
tu
ra
l
R
e
ge
ne
ra
ti
o
n
Assessment of Variable
The negative trend indicated during 1982 to 1992 is not good for the sustenance of forest
resources in the country.
3.2.4.2 Incidence of Insect and Pests
Insect pests are normally present all the time in forest areas and it is only when they cross certain
threshold the condition is called “out break”. Majority of insect pests are localized and general
feeders but some are quite specific and confine to a particular hosts only. There is lack of
systematically recorded data on incidence and damage by forest insects.
68 (114)
Table: Major Insect Pest Problems in Forests, Plantations and Nurseries
Insect pest species
Common
name
Order/family
Year of Epidemics/ Mortality
Cryptothelia
cramerii Westwood
Chir pine
defoliator
Lepidoptera :
Psychidae
First epidemic reported in 1885 from Tons Valley, Uttranchal.
Subsequently recorded from H.P. (1928), Kahhula, Pakistan
(1934). Recently reported from Rajouri (J&K) in 1989 – 1990.
5% mortality in 2000 ha. area, with 0.3 million trees in J&K;
net loss 22.5 million rupees.
Hoplocerambyx
spinicornis Newman
Sal heart
wood
borer
- do -
Epidemic dates back to 1899 in Singhbhoom, Bihar. Reported
from Assam (1906, 1961), H.P. (1‘948 – 1952), M.P. (1905,
1927 – 28, 1948-52, 1959-63), Uttranchal (1916-24, 1934-37,
1958-60, 1961, 1965), West Bengal (1931-34). Recently a very
heavy epidemic occurred in M.P. in 1998, affected some million
sal trees.
Hypsipyla robusta
Moore
Toon shoot
borer
- do -
A serious pest of toon and mahogony, capable of causing
100% mortality in seedlings and young plantations. In India,
some of the seriously infested toon plantations were destroyed,
causing loss of R.15-30 per acre. Also reported to cause
damage in Sri Lanka, Australia, Bangla Desh, Pakistan,
Nigeria and West Indies).
Ectropis deodarae
Prout
Deodar
defoliator
Lepidoptera:
Geometridae
Large areas of deodar forests in the outer ranges of north -
western and western Himalaya are often defoliated completely
by Ectropis deodarae, causing heavy mortality. Recently, an
epidemic of deodar defoliator was reported from Lolab Valley,
J&K. Mortality has been as high as 30%. Epidemics have
occurred at intervals of about 10 year and may last for 2 or 3
years.
Eutectona
machaeralis Walker
Teak
skeletonize
r
Lepidoptera :
Pyralidae
Major pests of teak, occurring throughout south Asia and some
parts of South-East Asia. Complete defoliation by the pests
results in more or less leaflessness during most of the growing
period. The damage varies from almost negligible to as much
as half of the total annual increment. The studies carried out in
the past estimate the loss to about 0.051 millions/ha/year.
Plecoptera reflexa
Guenee
Shisham
defoliator
Lepidoptera :
Noctuidae
Serious epidemic in Changa Manga and Khanewal forest
divisions (now in Pakistan) in 1899. Serious epidemics have
been recorded from Chichawatni and Khanewal in 1927, 1928,
1932 and in Ambala forest division in 1974 and 1975.
Dioryctria abietella
Devis & Schiffer
Mudlor
Chilgoza
cone borer
Lepidoptera :
Pyralidae
The insect causes, damage to cones and seeds of coniferous
species, covering major zoogeographical regions of the world
(North-West and Western Himalaya, Afghanistan and Europe
and North America). Reported 32.7% damage to Pinus taeda
in 1973-74, 1.5-=5.4% in Abies pindrow in Pakistan in 1980
and almost 100% loss in seeds in fully developed cones of
Pinus wallichiana in 1986 in Chakrata, Uttranchal.
Celosterna
scabrator Fabr.
Babul
shoot &
root borer
Coleoptera :
Cerambycidae
A most notorious pest of Acacia nilotica reported from Bera
(M.P.) in 1890. Incidence of borer attack upto 80% has been
reported from the babul planted in unsuitable sites. Reported to
be injurious to Acacia catechu, Cassia siamea, Casuarina
equisetifolia, Eucalyptus spp., Prosopis juliflora, P.spocigera,
Tectona grandis.
Eligma narcissus
Rothschild
Ailanthus
defoliator
Lepodoptera:
Noctuidae
Defoliates seedlings and young plants (upto 5 years old) in
plantations of Ailanthus excelsa and A.triphysa in pennisulan
India. During heavy infestation, about 20-40% larvae are found
in each leaf, causing heavy damage whereas in nurseries
complete defoliation (100%) may occur. A widely distributed
species in South – East Asia, east of Phillipines in the Oriental
region.
69 (114)
(follows from previous)
Insect pest species
Common
name
Order/family
Year of Epidemics/ Mortality
Eterusia pulchela
Khasi pine
defoliator
Lepidoptera :
Zygaeniidae
A large scale epidemic occurred in 1975 in 7500 ha. of Jaintia
hills and 2500 ha. in Khasi hills. Affected stands of 5-30 years;
heavy mortality (50%). Heavy defoliation occurred again in
1978. Two or more complete defoliations are sufficient to kill
the tree.
Apriona cinerea
Cheverolet
Poplar
stem borer
Coleoptera :
Cerambycidae
A serious problem in cultivation of exotic poplars in India.
Mostly 1-3 years old plants are more prone to borer attack.
Very common in North-West Himalaya and the adjoining
plains region.
Atteva fabriciella
Swedrus
Ailanthus
webworm
Lepidoptera :
Yponomentida
A major pest in young plantations of Ailanthus excelsa and
A.grandis is greater part of India and Pakistan. Repeated
defoliations result in increment loss, particularly in plantations
growing and hostile soil conditions. Also reported from
Kalimantan (Borneo).
Eucosoma
hypsidrves Meyrick
Spruce bud
Worm
Lepidoptera :
Eucosmidae
A major primary cause of mortality of Picea spp. in the
Himalayas. Trees of all ages are attacked. Heavy and repeated
infestation results in weakening of the host.
Calopepla leayana
Latreille
Gamha
defoliator
Coleoptera :
Chrysomelidae
A serious pest of gamhar plantations in Assam, Trefru. Heavy
infestation leads to drying up of shoots of young trees and the
trees remain leafless for about 4 months of the growing season
leading to ultimate death.
Melosoma populi
Linn.
Poplar
defoliator
Coleoptera :
Chrysomelidae
A serious pest of Poplars and Willows in the temperate
Himalayas from J&K to Arunachal Pradesh.
Clostera cupreata
Butler
& C. fulgurita
(Walker)
Poplar
defoliator
Lepidoptera :
Notodontidae
A major problem in poplar plantation in tarai region of Uttar
Pradesh since 1966 and in Punjab since 1986. Develop into
epidemic form after 3
rd
year of plantation of Poplars.
Dichomeris
eridantis Meyrick
Shisham
leaf roller
Lepidoptera :
Gelechidae
A major problem in Shisham plantations.
Lebeda nobilis
Walker
Chir pine
defoliator
Lepidoptera :
Lasciocampidae
Large scale epidemic defoliation in Sankosh Valley chir forest
in Bhutan from 1984 to 1986, led to large scale drying of chir.
All age classes of pines are attacked.
Lymantria obfuscate
Walker
Kashmir
Willow
defoliator
Lepidoptera :
Lymentridae
Most destructive pest of Willows, results in loss of increment:
trees may be killed if they are severely defoliated for more
than one year.
Malacosoma indica
Walker
Forest tent
cater pillar
Lepidoptera :
Lascocampidae
Widespread defoliation epidemics occur in North-West
Himalaya.
Tonica niviferana
Walker
Semul
shoot borer
Lepidoptera :
Oecophoridae
An important pest in Semul nurseries and young plantations.
The attacked shoots of the young plants die in due course. The
same plant may be attacked again and again. If the attack is
repeated consequently for some years, the young plants are
killed.
Hyblea puera Gram
Teak
defoliator
Lepidoptera :
Hybleaidae
Pest epidemics reported from time to time.
Assessment
The frequency and extent of incidence is increasing and it is not a good sign for sustenance of
forest resources in India.
70 (114)
3.2.4.3 Incidence Weeds Infestation
Invasion of forest lands by alien species or incidence of weeds is the most urgent problem faced
by forest resource managers. The forest weeds compete with native and desired forest flora for
light, moisture, nutrients and space. They include herbs, shrubs, vines and tree species. Table
gives a list of main weeds in forests of India. Survival and growth of selected trees is an
important aspect of forest management. Weeds compete with these trees for light, moisture,
nutrients and space
Definition No national definition is available.
Transformation Not necessary
Data and Temporal Trend
Not much data is available on this important variable; therefore development of temporal trend is
not available.
Table: Main Weeds in Forests of India
Species Distribution
Eupatorium odoratum
Assam, West Bengal, Bihar, Karnataka, Kerala, Goa, Western
Ghat region.
Lantana camara
Throughout India, in hilly regions up to 8000 ft. height.
Mallotus philippensis
Uttar Pradesh, Uttaranchal, Bihar, Sub-himalayan tract from
Punjab eastward ascending up to 4500 ft. West Bengal,
Central India.
Clerodendron viscoscum
Uttar Pradesh, Uttaranchal, Bihar, Nagaland up to 4500 ft.
height
Moghania chapper
In Sal forests of Uttar Pradesh and Bihar.
Ageratum conyzoides
Uttar Pradesh, Uttaranchal, Bihar,
Desmodium cylindrica
Uttar Pradesh, Uttaranchal, Bihar,
Erienthus munja
Tall grass in plantations throughout India
Sacharum spontaneum
Tall grass in plantations throughout India
Dendrophthoe falcate
Parasites in commercial forests of India
Scurulla parasitica
Parasites in commercial forests of India
Cuscuta reflexa
Parasites in commercial forests of India
Viscum monoicum
Uttar Pradesh, Sikkim, Meghalaya, Western Peninsula
Macrosolen cochinensis
Parasites in commercial forests of India
Mikania
Throughout India
Parthenium
Throughout India
Carthamus oxycantha
Throughout India
Argemone maxicana
Throughout India
Assessment
There is perception among experts that there is an increasing trend of weed infestation in forest
areas. Non availability of data makes the situation worse.
71 (114)
3.2.4.4 Incidence of Grazing in different Forest Types
In most of the forests in India, the level and nature of grazing, in general, exceeds the capacity of
the forests and thus is one of the most important factor for degradation of forests. One gues
estimates that about 100 million cattle graze in forest area against its capacity of about 28 million
livestock. This problem gets worse because, neither public not private grazing lands or range
lands are scientifically managed in India.
Definition No national definition is available
Transformation It is not necessary
Data and Temporal trends
The FSI also conducts a supplementary assessment of the extent of grazing when it is conducting
forest inventory in a forest area. The FSI has already covered about 80% of the forest area of the
country under ground inventories. It estimates that about 77.6 per cent of forest area of the
country is affected by grazing. Of this 17.9% of forest area is affected by high incidences of
grazing, 30.7% by medium and 29% by light grazing incidences. Following figure indicates the
extent of grazing in different forest types.
Incidence of Grazing in differnt Forest Types
28.2
25.6
10.2
31.2
30.2
32.4
19.3
26.6
28.2
30.1
36.6
25.3
13.4
11.9
33.9
16.9
0%
20%
40%
60%
80%
100%
Coniferous
Moist Deciduous
Dry Deciduous
W et and Semi-
evergreen
Forest Types
P
e
rc
ent
G
raz
in
g
No Grazing
Light
Medium
Heavy
Assessment
The forests are under very high incidence of grazing pressure that is more than their capacities.
Therefore, it may endanger their long-term sustainability.
3.2.4.5 Incidence of Fire
Frequent and unplanned fires adversely affect forest stock as well as flow of its goods and
services. About 54.7% of India’s forests are fire prone and of this about 9.2% forest areas are
72 (114)
affected by frequent forest fires and 45.5% forest areas by occasional fires (FSI, 1997). Further,
most of such forest fires are caused by man.
Definition There is no national definition for fire
Transformation Not necessary
Data and Temporal Trend
FSI conducted a study to estimate extent of fire in 1995 through 139 scenes on 1:1 million scale
with three lasses (i) fire affected, (ii) smoke and (iii) fire unaffected. An intensive ground
verification was done on related 349 toposheets at 1:50,000. The study revealed that during 1995
at national level about 2.31 percent of forest cover was affected by fire.
There is no other study at the national level to indicate the trend.
Assessment
No national level assessment is possible due to lack of data.
3.2.4.6 Incidence of Pollutants
The pollutants affect development of plant through their impact on photosynthesis and respiration
leading to modified distribution and sustenance of species and their foliar diseases. The
sustainability of the any forest relating to the impact of pollutants may be judged either looking
their absorbing and mitigation potential or looking the damages due to pollutants.
Definition
Term
Definition
Pollutant
Any substance, which causes pollution, is called a pollutant.
Explanation:
A pollutant may include any chemical or geo-chemical substance, biotic component or its
product, or physical factor that is released intentionally by man into the environment in such a
concentration that may have adverse, harmful or unpleasant effects.
Transformation Not needed
Data and Temporal Trends No Data is available
Assessment
The variable is important but lack of data limits any assessment.
73 (114)
3.2.4.7 Presence of Indicator Species
Certain indicator species help to judge the health and vitality of a forest. For example, the
presence of palms, orchids, ferns, arboreal mammals, owls, honey bees and butterflies may
reflect the stable and healthy forests. It is considered important that India identifies “keystone
species” and documents the presence, absence or abundance of such key indicator taxa within the
representative forest types.
Definition (UNEP )
No standard national definition is available
Term Definition
Indicator Species
A species whose status provides information on the overall condition of the
ecosystem and of other species in that ecosystem.
Explanation
It flags changes in biotic or abiotic conditions.
They reflect the quality and changes in environmental conditions as well as aspects
of community composition.
Transformation: No data is available hence no question of transformation.
Data and Temporal trend
Necessary information is not available. Recently, few Protected Areas have started systematic
monitoring of vegetation structures, rare plants and animals in the country but no assessment has
been done for various species as indicators of forest health.
Assessment
The variable is very useful but lack of data limits its utility.
3.2.4.7 Density of Forest Canopy
This variable is very important because it expresses the distribution of canopy defines the
composition, rates of growth and regeneration of forest stands as canopy controls distribution of
sunlight to plants. Any significant change in the forest canopy may have effect on forest
succession, growth and composition.
Definition
Term Definition
Canopy Density
Percent area of land covered by canopy of the trees
74 (114)
Transformation Not needed
Data and Temporal Trend
Following figures present the information on the percent of dense and open canopy forest in
India.
Trend on Dense and Open Canopy Density
61.70
38.30
59.70
58.47
60.76
60.66
60.66
59.66
56.69
40.30
41.53
39.24
39.34
39.34
40.45
43.41
35.00
40.00
45.00
50.00
55.00
60.00
65.00
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
Year
P
e
rcent
Dense
Open
Assessment
The trend indicates the density of closed forest is increasing. This is a good sign for sustenance of
forest resources in India.
3.2.4.8 Status of Forest Fragmentation
The forest fragmentation directly affects the local ecological processes processes both in the short
as well as in the long-run and may endanger sustainability of resulting smaller patches of forests.
The loss of connectivity between too patches may threaten existence of certain floral and faunal
species and may also reduce adaptation resiliency of forest system to climate change. It may also
lead to forest and land degradation, soil erosion and depeletion of water storage and flow.
Therefore, the “forest fragmentation” is one of key factors for monitoring of sustainability of
forest resources.
Definition (CBD’s definition)
No national standard definition is available
Term Definition
Forest Fragmentation
Any process that results in the conversion of formerly continuous forest into patches
of forest separated by non-forest (lands).
75 (114)
Transformation Not considered necessary
Data and Temporal trend
The following presents information on the percentage of fragmented forest in 1980, 1990 and
2000 based on the independent remote sensing implemented by FAO, Rome.
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