Home  EnviroNews  International Conferences  Picture Gallery  Sponsor  Contact  Search  Site Map

Vol. 15 No. 4 - October 2009

Looking Afresh At Urban Greens

By: Monika Koul* and A.K. Bhatnagar**

Adequate tree cover is important for economic and ecological security. Experts recommend that at least a third of India's geographical area should be tree clad for sustainable environment and economic development. The total forest cover of our country as per 2005 assessment is 677,088 km, constituting 20.6% of the geographic area. Of this, the tree cover has been estimated as 91,663 sq. km, which is about 2.79 percent of the country's geographical area (Forest Survey of India, 2005). Rampant felling of trees, on account of urbanization and developmental activities such as construction of roads and railway lines, is seen all over India. Data available on land use pattern clearly depicts that India has a skewed land use pattern.  State  of  Environment  India Report  (2009) released by  the Ministry of  Environment  and  Forests  states  that over  50%  of  our  total  land is under agriculture, 17% is barren and uncultivable, 13% is culturable wasteland and barely 20%  is under some  form of  the forests. The per capita forest area available in India is 0.06 ha, which is much below the world average of 0.64 ha per person. National Forestry Action Programme  (NFAP)  of Government  of India  states  that besides protecting  the existing  forest  resources,  expansion of tree cover  is  important  for maintaining the  ecological  balance.  Therefore, plantations are to be carried out on the existing available  pockets  as  well  as areas which  are  devoid  of  tree  cover.   With  no  additional  area  available  for afforestation,  the  focus  during  the  last three  decades  has  been  on  social forestry/community  forestry  and  road-side/canal  side  tree  plantations. With our towns and cities expanding rapidly, we need to think afresh about urban tree plantations too. These should not only contribute  to  aesthetics,  but  also  add their  bit  to  overall  national  tree  cover targets and meet some of the residents' small  timber  and  non-timber  plant product requirements.

Importance of trees in cities-aesthetics and ecology

India's cities and their suburbs have expanded at the cost of farmlands, which in turn have encroached upon forests.  Population explosion, economic development, industrialization and vehicular pollution are magnifying the urban problems and contributing to further loss of green cover. Nearly half of the population now resides in the cities and towns.  The urban elite are conscious of the social and aesthetic value of trees.  Yet, it has never been considered desirable that the cities should meet some of their own timber and firewood requirements. Cities need enhanced tree cover for their ecological needs-conserving  soil  and  water  and providing habitat  for variety of  life  forms such  as  birds,  animals,  insects  and microorganisms.  The green belts also serve as lungs for purifying air in cities, act as sink for pollutants, check the flow of dust and aid in bringing down noise levels. Scientists all over the world are looking at  trees  in urban areas as entities which provide ecological services such as  cleansing  of  the  environment, recycling of the wastes, maintenance of seasonal  cycles  and  acting  as  carbon sequestration  units  for  mitigating  the effects  of  global warming  and  climate change.

Most of  the people  responsible  for urban development  agree  that  plants  contribute towards the environmental quality and  there  are  ample  social  and psychological  benefits  of  contact with plants.  Recent public health research has deepened our understanding of the positive effects of plants on physical and mental well being. Social scientists have given conclusive evidence of the role of greenery in helping to cope up with stress and anxiety. Working and  living near  quality  green  spaces  can  satisfy people, help  them  relax and  influence their mood and ability  to concentrate  for long. Urban pockets having adequate green cover harbour a lot of biodiversity too. The green patches serve as nesting ground for many birds, and act as macro and microhabitats for primates, rodents, insects, epiphytes, lichens, fungi and variety of other living organisms. Alternative habitats  for a variety of  living organisms  in urban pockets enhance  the aesthetic  value  of  city  landscapes  and thus  help  in  enhancing  the  scope  of ecotourism. When  the  spaces  next  to residences  are  green,  these  become more attractive, comfortable and draw a lot  of  people  to  them.  Such settings serve as foundation for social ties, ideal places for people to relax and children to play.

Present urban management practices

Why  cities  and  towns  should  not produce  some of  their own  tree-based requirements  is  a  question  which should now be discussed. The cities are a huge drain on forests and tree cover of rural areas for their timber and fuel/firewood needs.  Urban  centres draw huge quantities of wood from the forests  and  countryside,  the  poor  for firewood  and  the  better  off  for construction  and  furniture.  Massive programmes  and  projects  have  been undertaken  by  government  and  non-government agencies to enhance urban tree  cover  over  the  years. Millions  of saplings  are  distributed  and  planted each  year  in  cities  such  as  Delhi, Mumbai,  Bangalore,  Kolkata  and Chennai.  Tree plantations  in most of  the Indian  cities  are  undertaken  by horticulture  departments  or municipal boards  or  councils.  The  city  councils plant  large number of  trees during  the monsoon  period,  but  fail  to  take adequate care during  the dry period  that follows.  Juvenile mortality rate is very high. To achieve its full growth, a  tree requires a lot of care during early years of growth. Attention has to be paid for proper  placement  of  the  tree  in  the ground,  and  its  protection  from ruminants.  Many  horticulturists  recommend  staking  the  young  trees irrespective  of  the  type  of  species  to which  the  tree belongs. Since, most of the  trees planted  in  city parks, on  the roadsides,  in  the  parking  lots,  in recreation parks and as shelter belts are taken  from nurseries,  a newly planted sapling  in  these areas  requires manuring and irrigation at regular intervals. Novel soil reclamation and replenishment techniques need to be applied for improving the health of soil. This is very important for proper establishment of the tree in the new habitat. Compaction of soil in cities is also taking huge toll of trees. Many large trees are razed to the ground whenever there are strong winds and rain. Due to poor soil aeration, roots of such trees are shallow and weak.   Concretization of roads is considered worst for the tree health.  It causes choking of roots and hence injuries and death.  It  also  results  in  destruction  of flora  and  fauna  below  and  above ground.  Ministry of Urban Development and Poverty Alleviation has clearly specified in its guidelines that an area of 1.8X1.8m2 foot should be left “uncemented” around each tree to ensure that it gets enough breathing space. However, such recommendations based on common sense are not followed.

Road digging for laying cables and pipes are major threats, requiring saplings to be planted in the same place again and again.  However,  once  the  tree  has survived,  there  is  a  total  ban  on  its cutting,  removal  or  even  husbandry. Public perception, compounded by the media, is that once a tree has grown, it should  not  be  cut  or  trimmed  for developmental  purposes  even  if  it  is overgrown, old or hazardous. The only way a large tree or its branches can fall is when there is a storm or rain. Extraction of non-timber products too is often not allowed. Pruning helps a tree to attain its maximum productivity, sustainable growth and tackles the requirements of fodder and fuel wood to some extent. It facilitates the growth of new shoots and formation of a wide canopy. Dormant buds after pruning produce new branches. If twigs and tops of trees are collected, and  if old and underdeveloped  trees are  replaced  regularly,  it could help generate some wood and revenue and at  the same  time enhance  landscape and  organization  of  trees.  Studies conducted on urban trees by Singapore Forest Department suggest that the average life expectancy of most of urban trees is about 50 years. Over the first three years of growth, 20% of the trees planted in urban areas die. Most show visible  symptoms of aging  such as  loss of leaves,  falling  of  branches  and susceptibility  to  pests  and  pathogens. Such  trees  showing  negligible  growth over a time period and fewer number of leaves  relative  to  the  size  of  trees, should be allowed to cut and replaced by new  saplings.

Species selection

Selection of trees for plantation is the most critical factor. What species should be planted is much less a matter of concern now than it was when many of our large cities were planned. Trees in older  planned  areas  of  Hyderabad, Pune, New Delhi,  Lucknow,  Kolkota, and Bangalore are far more diverse and systematically planted  than  in  the newer townships and  suburbs. A comparison of  the  trees planted  in major cities before or  just  after  independence with  those being  planted  now  would  be  very revealing.  The  British  introduced hardwood trees in India from their other colonies  through  specially  created arboretums  and  gardens  in  Kolkata, Bangalore,  Darjeeling,  Ooty,  Dehradun,  Saharanpur,  Panchmari,  Manali and  elsewhere.  Establishment  of  city national parks in Mumbai and Chennai and  botanical  gardens  in  Lucknow, Bangalore  and  Kolkota  are  some examples of well thought out and well planned  urban  green  belts.  The reforestation of Delhi Ridge (1912) and declaration of Delhi Ridge as a Reserve Forest is also a milestone in conservation of urban greenery. Considering the strategic  importance  of  these  green belts, species selection, introduction of exotics  and  landscape  features  were given  considerable  attention.  In the concrete jungles these still serve as green lungs.  The  present  day municipalities, despite their huge budgets and jet-set  executives  and  councillors, neither  follow  the  traditions  nor  have introduced any innovations in their tree plantation programmes. Trees that can be multiplied easily and require no post-plantation care are the favourites. Thus, we  can  see  on  most  of  the  roads  a mixture  of  big  and  small  trees  of eucalyptus, casuarina, ashoka, alstonia, neem,  banyan,  mulberry  and  sisoo. Beautiful palms, conifers and ornamental  trees  such  as  corals,  flame  of  the forest,  silk  cotton,  bauhinias,  crape myrtle, temple  tree, bottle brush,  Indian laburnum, gulmohur and squirtwort are rarely  planted  now  as  these  are considered  'commercial',    prone  to pilferage  and  difficult  to  sustain.  The regulation  and  publication  of Gazette Notification defining  the  trees  that can be  planted  by  official  agencies  in  a major  city  also  leaves  horticulturists with much  less  choice  in  selection  of species. Dr M.S. Randhawa, in his book entitled 'Flowering Trees, ' has mentioned that during the British rule evergreen tree plantations gained more attention. Trees such as tamarind, arjuna and African sausage tree were seen as good for hot summer climate. Plantation of beautiful deciduous trees which formed an important component of the vegetation was seriously neglected. By recommending  a  preponderance  of ever green species' for the arid habitat in  Delhi  many  native  species  were edged  towards  local extinction.

Incidentally,  many  trees  with  wind borne  pollen,  which  cause  allergic disorders  in  a  substantial  part  of  the human  population,  still  find  place  on city  roadsides. Such trees, including eucalyptus, wattle and mulberry are in the lists of permissible trees in many cities.  It  is  observed  that  in  Delhi multiple  government  agencies  viz. Delhi  Development  Authority  (DDA), Municipal Corporation of Delhi (MCD), Cantonment   Board  and  Forest  Department  continue  to  plant  several allergenically  significant  trees.

Selection of trees for plantation in urban areas revolves around convenience. The basis of selection is very narrow. Saplings  raised  on  mass  scale  are distributed and planted without  taking into  account  the  importance  and  the role  the  tree  is  going  to  play  in  a particular  habitat.  The  concept  of landscaping is still alien to our planners with  the  result  that  the  trees  are haphazardly  planted,  and  the  trees planted  on  roadsides  are  no  different from  those  in parks or  schools, offices and  hospitals.  Some of the most beautiful trees flower during February-March, coinciding with breeding season of several birds.  The  flowers  provide nectar  to  the  birds  in  return  for pollination  service  essential  for  their reproductive cycle. To attract birds, the trees produce beautiful flowers.  The bird-pollinated trees, such as silk cotton, flame of the forest, Indian coral tree and Bauhinia spp. make the landscape majestic. The African sausage tree is pollinated by bats. The Arjuna has fruits that are chewed up by bats that help in seed dispersal. Manila tamarind has a red aril covering a part of the seed which attracts birds.  Thus, a variety of trees support different birds, bats and insects and make the human habitat lively and biodiversity rich. Rare and endangered species of trees can be reintroduced in certain pockets as is being done in the Aravalli foot hills in the NCR. Kala siris (Albizia  odoratissima),  frankincense tree  (Boswellia  serrata),  kulu  tree (Sterculia urens) and pisangan (Grewia flavescens)  which  were  the  charac-teristic of Aravallis can be reintroduced in  the  city  forests of Delhi  and  Jaipur.  Many cities can be safe heavens for RET trees.  Multipurpose  trees,  especially those of medicinal importance, can be introduced  in  some  selected  pockets where  adequate  care  can  be  taken. Since, natural products are already catching frenzy of city populations,  such introductions can also help  in revenue generation.  Trees  such  as  emblic myobalam,  soapnut,  marking  nut, drumstick, neem and butter tree which were  once  important  components  of vegetation  of  many  cities  should  be grown more frequently. A planted area as  a  whole  with  trees,  shrubs  and  a ground  cover  forms  a  living  and dynamic system with better ecological services.  The  selection  of  trees  for plantations  should  be  done  in  accordance  with  the  type  of  land/pysico-chemical properties of the soil available for plantation.

Estimation of green cover

A flaw with the estimation of green cover is another area which eludes the urban foresters. Tree records, based on number of saplings planted, and remote sensing data depicting everything green as a  part  of  tree  cover,  often  give exaggerated  data.  Phytosociological and  quantitative  vegetation  analysis procedures, giving more precise details of  about  density,  abundance,  basal cover area and canopy cover area, need to  reinstated  and  used  to  supplement satellite  data.  The  government machinery  is  often  confused  and  stands divided  on  many  aspects  related  to management  of  tree  cover.  Focus has always been on the number of trees planted each year. Monitoring  on  the basis  of  tree  clad  area  can  give  better picture of  the city's green area. Research in urban forestry and management of trees is yet another area where no public funding or interest is apparent.  Lot of research is carried out on management and improvement of forest tree species. However, urban trees growing in different ecological settings are not being studied.  Ministries and other funding agencies need to allocate funds for research on ecological, economic, aesthetic and psychological aspects of urban trees.

Mitigation of climate change

With  the  United  Nations  Framework Convention  on  Climate  Change (UNFCCC)  now  allowing  countries  to earn  credits  for  planting  trees,  which function as carbon sinks, the cities can earn  carbon  credits  under  the  clean development mechanism (CDM). Delhi and Himachal Pradesh have already identified land for tree plantation and agreed to increase the green cover and earn these credits to boost their economy. Such plantation drives are already taking place in tropical countries. Singapore  and Malaysia  are front  runners  in  their  profitable endeavour because of  enhanced  green cover  and  modern  scientific  tree management  strategies.


Urban forestry practices in India are anachronistic.  A  paradigm  shift  in planning  and management  framework is  required  for  tree  plantations  to  be aesthetic, cost-effective and of multiple utility. The choice of species needs to be expanded to include a much larger diversity of the indigenous and exotics. Ornamental trees, mostly insect and bird pollinated, will add some colour to drab landscape of Indian cities. Palms and conifers at appropriate locations can help break the monotony.  Trees deserve more care and hospitality, especially in the early stages.  Regulations  that  limit  replacement  of old,  diseased  and  crooked  trees,  or those at unsuitable  locations, need  to be dropped,  and  urban  greenery  should increasingly  be  treated  as  dynamic, productive systems. The  large,  resourceful  horticultural  and  forestry  departments  in major  cities  should  invest  in tree  improvement,  landscaping  and resource utilization technologies. Many RET and medicinal trees can be conserved in urban plantations, to take off the pressure in the wild. The present method  of  fixing  targets  based  on number  of saplings planted annually also needs to be replaced with modern methods  of  tree  cover  and  biomass assessment  by  remote  sensing. Trees that are good in carbon sequestration can help mitigate climate change, and in addition earn carbon credits.  Finally, involvement of citizenry, through education and incentives and individual choice and care of trees will go a long way in fostering good people-tree relationship.


*Assistant Professor, Department of Botany, Hans Raj College, University of Delhi, Delhi - 110 007 E-mail: drmkoul@gmail.com

**Professor, Department of Botany, University of Delhi, Delhi - 110 007 E-mail: akb_du@rediffmail.com

This article has been reproduced from the archives of EnviroNews - Newsletter of ISEB India.

Home | EnviroNews | International Conferences | Picture Gallery | Sponsor | Join/Contact | What others say | Search | Site Map

Please report broken links and errors on page/website to webmaster@isebindia.com