Monitoring At-Risk Trees Using Spectral Reflectance Data from Satellites

A desktop early warning method for arborists and tree management to carry out migitating actions.
Uses data from two commercial satellites: WorldView-2 and WorldView-3.
Satellite data processed by remote-sensing software to generate spectral reflectance of individual trees, and compared with the data of previous year(s).
Have to be using cloud-free images, although software could compensate for other atmospheric effect on images.
Spectral reflectance relates to chlorophyll content and leaf cellular structure, which correlates to tree stress and/or structural stability. These symptoms could not be readily observed by the naked eye.

For the following analysis, data of the spectral bands of red, red edge, and near-infrared 1 and 2 on 25 May 2010 and 17 April 2015 (five years apart) were acquired from WorldView2 satellite.
- Three Banyan trees (Ficus microcarpa) in Hong Kong.

Over the five years, the drop in the spectral reflectance of the near-infrared band for Tree #1 was 4%, Tree #2 was 3.5%, and Tree #3 was over 7%.
The author believes that there is a direct correlection between the drop in spectral reflectance and the closeness to the date of collapse.
Based on the indicators, all three trees were stressed and structurally unstable, leading to their failure after 96, 94 and 2 days, respectively.

In a back-dated analysis for a tree that has already fallen on 10 August 2016, data dated 2 September 2014 and 8 September 2015 (one year apart) were acquired from WorldView2 satellite.
- Three Elm trees (Ulmus sp.) in Oslo, Norway.

In just one year, the drop in the spectral reflectance of the near-infrared band for Fallen Tree #1 was 5%. There was not much variation in spectral reflectance in the adjacent Alive Tree #2 and Alive Tree #3.

Conclusion:
This method is not meant to diagnose the cause of stress and structural instability.
Presents more objective and quantitative means to measure the health of trees.
Could be combined with field inspection to enhance the management of trees by implementing timely mitigating actions.

Reference:
International Society of Arboriculture's Arborist News, Volume 26, Number 2, April 2017

Terrarium Basin/Sink Countertop

 A basin/sink countertop with a terrarium, which can be accessed from the doors in front.

Can be used from both sides with a swivel tap. LED light strip illustrates how the waste water would flow, obviously.

The tap was not connected to a water source here, but this is a working model that can function as designed.

My attempt in instructing the fabrication of this countertop. Using a CAD software that is not Autocad.

 Maybe a rectangular basin like this would be more suitable?

A fish tank sink that was a inspiration to the above design.

Alternatively, it can be used to contain a Zen garden.

News Sharing: At Rs 22 lakh a month, Mumbai Metro gets specialist to transplant trees

The Times of India 12 Mar 2017

MUMBAI: Facing the heat from citizens over the indiscriminate cutting of trees for the Rs 23,000 crore Metro III project, an arborist has been appointed for a tree preservation management plan.

An arborist is a specialist in cultivation and care of trees, including prevention of tree diseases.

The arborist, Simon Leong from Singapore, has been appointed by Mumbai Metro Rail Corporation Ltd's (MMRCL) general consultants, Maple Consortium, for six months at US $33,000 -that's about Rs 22 lakh-a month besides accommodation and return air fare (four trips). The appointment was approved in January this year after the MMRCL had already identified trees to be cut. Till date, around 100 trees in south Mumbai have been cut.

Activists are questioning the cost being incurred for transplanting trees, given the fact that in the past no transplanted tree has survived. "It's a complete eyewash. Tree plantation or transplantation is a complete scam in the city as norms are very lax," said Zoru Bathena of Aarey Conservation Group.

The MMRCL has proposed to cuttransplant 5,012 trees along the 33.5 km route comprising 26 stations. The last station is proposed at Aarey Colony where the metro car shed is to be located.

Nina Verma, a Churchgate resident, filed a petition against cutting of trees while Pervin Jehangir, aCuffe Parade resident, filed a writ against due process not being followed besides other issues.The Bombay high court, which, in February , stayed the cutting of trees is hearing both matters together.

Through the Right to Information Act, residents learnt that trees from ColabaCuffe Parade are to be transplanted at Wadala in marshland where even mangroves do not grow . Also, new trees meant for Colaba and Cuffe Parade are to be planted as compensatory afforestation in Wadala in the marshland.

The law mandates that for every tree that is cut, three have to be planted within 30 days. In this case, not one tree has been planted yet.

Ashwini Bhide, managing director, MMRCL, said the decision to appoint the arborist was approved by the Tree Authority in December 2016January 2017 with a large number of trees (1,700) which were slated to be transplanted.

"Based on search around India and abroad, our general consultants suggested that the Singapore expert had a good track record of tree plantation and survival. He (Leong) will visit Mumbai over the next 12-18 months and helping MMRC contractors address this crucial responsibility ," said Bhide.

Bhide said MMRCL has 43 hectares for tree plantationtransplantation of which 30 hectares are at Aarey . She said the marshland at Wadala would "obviously be avoided or suitable trees in consultation with the civic garden department will be planted."

Bhide did not respond to questions on whether the tree preservation management plan will be shared with citizens. She said the tree cover at metro stations will be restored but did not give a timeline.

[Also in: http://indianexpress.com/article/cities/mumbai/rs-21-lakh-a-month-mmrc-hires-tree-consultant-4565863/]

Biostimulant and Fish Liver Cod Oil Used on Trees

A recent TV show featured lesser known jobs in Singapore, called Sherlock at Work and it was hosted by Pornsak Prajakwit. In episode 5, the topic was on arborists, and Pornsak followed an arborist around for a "day in the life of an arborist". The show was uploaded to Toggle Video on 23 Nov 2016.

In one segment, after showing Pornsak on the use of resistograph and reasoned that the tree she was examining seemed to be in good health, she proceeded to ask Pornsak to apply mulch at the tree base. Following that, biostimulants and fish liver cod oil was applied into the ground near the tree using a hollow probe.

Liquid tank from which the biostimulant and fish liver cod oil was pumped from. (Screengrab credit: Mediacorp)

Ta-da biostimulant. (Screengrab credit: Mediacorp)

The host of the show applying the liquid mixture into the ground and the arborist supervised. Note the girth of the tree being treated and distance from the tree that probe was inserted. (Screengrab credit: Mediacorp)

Liquid emerging from the ground, or did the liquid not go into the ground? (Screengrab credit: Mediacorp)

Root spread of trees

The rule of thumb in arboriculture states the following regarding root spread:
1. Tree root systems extend out several times of the tree's diameter (depending on the age of tree).
2. More than 60 percent of the absorbing root system is beyond the dripline.
3. Most roots are in the top foot (30.5 cm) of soil.

The hollow probe should be inserted further away from the tree, given the advanced age of the tree, as most of the absorbing roots that takes in water and nutrients are located at the edge of the root system (beyond the dripline). In addition, since a fancy concoction was being used, it should be applied deeper than the surface of the ground, in order to avoid being absorbed by the grasses, being evaporated, and flowing away.

What are biostimulants?

Biostimulants are a group of compounds that promote favourable plant responses and are non-nutritional. Common commercial biostimulants contain many, if not all of the following ingredients:
- Plant hormones/Plant growth regulators
- Humic compounds
- Sea kelp extract and/or organic matter

Some of the claims reported by biostimulant manufacturers include:
- Stimulate plant responses and work in all weather conditions
- Increase natural plant toxins, repelling pests
- Increase microbial root protection from soil pathogens
- Improve root development
- Improve drought tolerance
- Increases nutrient uptake
- Stimulate plant's immune system
- Produce deeper roots
- Improve stress tolerance
- Accelerate establishment
- Increases Cation Exchange Capacity
- Enhances fertilisation and reduces leaching
- Detoxify chemical residues and heavy metals
- Increase stomata opening and plant transpiration

University studies on biostimulants do not fully agree with the claims usually made by manufacturers especially with regards to reducing fertiliser and pesticide use. However, there are positive reports that biostimulants show potential uses in turf under stress conditions and promote favourable nutrient mobilisation, although the responses to biostimulant may vary depending upon the biostimulant formulation and among species.

Harris et al. (1997) concluded that biostimulants appeared to be not useful if good transplanting methods were practiced with burlapped trees. This is consistent with the principle that under normal growing conditions, plants are self-sufficient and do not respond to an exogenous supply of hormones.

Another group of researchers (Zhang and Schmidtt, 1999) found that biostimulants does not stimulate much plant growth. One could conclude that a balanced fertiliser and compost application produces biostimulant-like responses, i.e., shoot growth, increase nutrient uptake, and photosynthate ("food" made by the plant with photosynthesis) translocation.

References

Harris, J. R., Fanelli, J., and Knight P. 1997. SNA Research Conference. 42: 369-372

Zhang, X. and Schmidt, R. E. 1999. Biostimulating turf-grasses. Ground Maintenance. 34(11): 14-32

 Show credits (Screengrab credit: Mediacorp)

Arboriculture Happenings at Bugis Area

The reason why girth is measured by running a measuring tape around the trunk instead of using a huge pair of calipers.

Scholars Residence previously PUB Staff Quarters circa 2013

Tembusu Tree Fell in Singapore Botanic Garden, Killing One

On Feb 11 (Sat) at about 4.30pm, a Tembusu tree 40m tall with a 6.5m girth fell in the Singapore Botanic Gardens, killing a woman who was with her husband and two children, and a woman who was with her friends was injured. The Tembusu tree was estimated to be 270 year old and had been on the site of the Botanic Gardens when it was established in 1859. The site was managed by the National Parks Board (NParks).

 The fallen Tembusu tree being assessed by investigators. (Photo credit: Today Online)

 

The Tembusu tree in Palm Valley of Singapore Botanic Gardens, taken on May 2014. (Photo credit: Google Streetview)

Photos of the Tembusu tree, which was a Heritage Tree, was taken down from the NParks website after the incident. The unique ID of the tree is HT 2001-34.

Screenshot of cache of the National Parks Board website, as it appeared on 28 Jan 2017. Note the "Last updated on 11 May 2016" at the bottom.

Screenshot of cache of the National Parks Board website, as it appeared on 28 Jan 2017. Note the "Last updated on 11 May 2016" at the bottom.

Screenshot of the the National Parks Board website captured on 12 Feb 2017. Note the "Last updated on 12 Februrary 2017" at the bottom.

Mr Simon Leong, an arborist of Urban Forester said on evening news that the soil may be satured after heavy rain, and stability of the tree will be "compromised". Continuing, he mentioned that after a "slight movement of the soil condition", the wind load from the tree may be "too big" and that is why it "can come down by itself". He added that "root support system" could help stabilise trees. [source: https://www.youtube.com/watch?v=S8R6lBIwZ_Q]

Screenshot of the "root support system" that Simon Leong mentioned in that interview.

Mr Lahiru Wijedasa, a former senior arborist at Singapore Botanic Gardens said that the tree was "unlikely to have fallen due to the lack of space". And that recent winds and rain could cause a "compromised" tree to be uprooted. [source: http://news.asiaone.com/news/singapore/botanic-gardens-tragedy-not-likely-tree-fell-owing-lack-space]

Mr Ng Tze Peng, an arborist of TP Arbo Care suggested that the investigators would have to study the whole tree, especially its root system, and environment and weather at the time of the incident. [source: http://www.channelnewsasia.com/news/singapore/botanic-gardens-tembusu-tree-that-fell-last-inspected-in/3511820.html]

Mr Andy Tan, managing director of Tan Huan Arboriculture Services opined that the probable cause of the tree failure was attributed to "water-logging due to recent heavy rains, resulting in surrounding soil to loosen and roots to rot". He added that "strong winds... could have further exacerbated the problem".
[source: http://www.channelnewsasia.com/news/singapore/botanic-gardens-tembusu-tree-that-fell-last-inspected-in/3511820.html]

A few days after the incident, on 13 Feb (Mon), a Rain tree on the site of student apartments [Scholars Residence] at Yuan Ching Road fell and injured a woman. The site was managed by the Singapore Land Authority (SLA). [source: http://www.channelnewsasia.com/news/singapore/woman-in-icu-after-getting-hit-by-falling-tree-at-yuan-ching/3515594.html]
A manager of the student apartments said that "this was the second time a  tree had fallen there". An earlier incident happened "last year [2016] but no one was injured". [source: http://www.straitstimes.com/singapore/woman-seriously-injured-by-falling-tree-in-carpark]

The tree fell onto the door of a lorry and on a woman. (Photo credit: ST Reader via ST)