E-Paper
Chandigarh: Tree health survey in 45 sectors completed
MC has removed nine trees on the recommendation of the institute which were found hollow during the ultrasound survey. So far, the team of FRI has surveyed as many as 1,34,000 trees, covering more than 45 sectors in Chandigarh, and has also carried out ultrasound on more than 300 trees.
The Chandigarh municipal corporation (MC) along with Dehradun-based Forest Research Institute (FRI) has completed tree enumeration and health status assessment of trees in the city’s sectoral areas and will now start the survey in erstwhile villages.
So far, the team of FRI has surveyed as many as 1,34,000 trees, covering more than 45 sectors in Chandigarh, and has also carried out ultrasound on more than 300 trees. In response to it, the MC has already removed nine trees on the recommendation of the institute, which were found ‘hollow’ during the ultrasound survey.
Since September last year, FRI, the government institute, is doing enumeration of standing trees in MC’s jurisdiction, evaluating their health and tree hollowness status, at a cost of ₹23.33 lakh.
“The team from FRI Dehradun visited the city and carried out the survey from time to time which included physical survey as well as carrying out ultrasound of the vulnerable trees to be recommended for removal in order to avoid danger in the rains and strong winds. The team hopes to cover the entire area by the end of the year and submit their report as to health status of the trees and the trees which are dead and dry and the trees which are required to be removed based on the ultrasound survey being carried out by the institute,” said MC commissioner Anindita Mitra, adding that nine trees have already been cut which were found hollow during the survey.
The tree enumeration is being conducted after visiting each site and observations are being made for insect pests, such as sapsuckers, defoliators, borers, and terminating infesting trees followed by sample collection, insect identification and recommendations for their management. The institute then investigates individual trees for signs and symptoms of diseases, after conducting sample collection, laboratory isolation and identification of pathogens.
The institute also determines ultrasonic velocity along multiple transverse directions of the tree trunk to study tree trunk hollowness. Based on the ultrasonic velocity, central hollowness of the tree trunk is estimated. Only potential hazardous trees are being tested for this purpose, at an extra cost of ₹400 per tree.
Last census
In 2017, the civic body’s horticulture department had conducted the first tree census in the city, but they had no scientific methodology for counting trees and assessing their conditions. A total of 1.65 lakh trees were logged in the census and 262 trees were found to be dangerous and 1,029 dead or dry.
Chandigarh has a total forest cover of 22.88 sq km and the tree cover is estimated at 15 sq km, which is 33% of the geographical area of the union territory. With ageing, the vigour of trees may decline, making them susceptible to attacks by pathogens and insect pests. Many diseases such as heart rots and root rots, make the trees vulnerable to wind throw. The trees may get uprooted, or the trunk breaks in the hollow region becoming a threat to life and property. Thus, physiological examination of the trees as well as soil analysis is required to identify biotic and abiotic factors contributing to decline in tree health and factors for various problems.
On July 8, 2022, a heritage peepal tree had fallen at Carmel Convent School, Sector 9, Chandigarh, killing a 16-year-old girl and injuring 19 others. In addition, there have been numerous instances of vehicles and other property damage as a result of tree cutting.
