Singapore Botanic Gardens (SBG), A Short Walk Along "Main Street"

Going past the scene of "the incident". As if nothing happened, but just so happened there was some improvement works.

Taken on 31 Aug 2017 at Palm Valley. As if the Tembusu tree was never there in the first place.

Taken on 31 Aug 2017 at Palm Valley. Note the asphalt patchwork on the pavement.

Taken on 9 Mar 2018 at Palm Valley. Note that the whole stretch of pavement was milled and re-surfaced.

Palaquium obovatum - would exudate a white latax, which is said to form a low quality rubber. Note that this tree was not protected by a barricade.

If people knew that this tree would ooze latax when its bark is cut like the rubber tree, it would be caged up as well.

Like this fella, Hevea brasiliensis or Para Rubber tree. It has some visible "scar marks" on the trunk already.

Hence this notice for people to keep their itchy hands off.

A gift from afar.

Cola gigantea planted by Nelson Mandela when he was president of South Africa in 1997. What is currently happening in South Africa is a shame though.

"its relative, Cola nitida, should be better known as it was the source of the original flavouring used in, and the name given to popular cola drinks such as Coca-cola and Pepsi-cola."
A few decades ago, there was a hoo-ha alleging that Coca-cola and/or Pepsi added cocaine to their drinks, and it was pointed that that was the reason why they were so "addictive".

"seen as a street tree in Singapore, e.g., along Alexandra Road..."

Above, some Cola gigantea photographed along Alexandra Road. Of course, looking nothing like the heritage tree aesthetic-wise.

Some larger Cola gigantea beside Kallang MRT station.

Pity that the trees along this stretch, including the adjacent Ficus trees were crown raised. Photo taken on 24 Oct 2016.

Specifications for Soil Mixture for General Landscaping Use

Specifications for Soil Mixture for General Landscaping Use
CS A03: 2013

Formerly CS A01:2009 (Specifications for Soil Mixture for General Landscaping Use) and CS A02:2009 (Specifications for Composts and Mulches).

Seems that the Centre for Urban Greenery and Ecology (CUGE) have combined the earlier two standards into one. CS A03: 2013 sells for S$10 incl. GST at the Singapore Botanic Gardens Shop.

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Changes from CS A01:2009 and CS A02:2009 to CS A03: 2013
1.3    Definitions, page 7 -> 1.3    Definitions, page 6

Addition of definitions of Soil Quality, Top Soil, Bioassay, Soil pH, Foreign Matter
Transfer of definitions of Pasteurisation, Compost Maturity, Plant Propagule, Mulch

Added section on soil profile in CS A03: 2013
1.4    Soil Profile, page 9

i.e., O horizon, A horizon, B horizon, C horizon, R horizon

No change from CS A01:2009 to CS A03: 2013
1.4    Soil Texture Classification, page 8 -> 1.5    Soil Texture Classification, page 8

Addition from CS A01:2009 to CS A03: 2013
1.5    Limits of the Various Classes of Soil Texture, page 9 -> 1.6    Various Classes of Soil Texture, page 11

Composition of sand, silt and clay of different soil textural class.

Changes from CS A01:2009 to CS A03: 2013
2.4    Soil Mix Composition, page 18 -> 2.1 Soil Mix Composition, page 12

CS A03: 2013 omitted soil mix composition for "general landscape uses which requires soil mix with higher porosity", and changed the soil mix composition for "general landscape applications" to 3 parts top soil, 2 parts compost and 1 part sand "by dry weight", as opposed to 3 parts clay loam, 2 parts compost and 1 part sand "by volume" in CS A01:2009.

CS A03: 2013 added a note that mixture of ASM by volume (as it was in CS A01:2009) applies only when the components have similar bulk densities. But they do not, as show below (units in g/cm3).

• Clay loam: 1.45-1.55 [UFL IFAS]
• Silt loam: 1.4 - 1.55 [UFL IFAS]
• Sand loam: 1.55-1.75 [UFL IFAS]
• Top soil: 1.0 - 1.4 [CS A03: 2013]
• Compost (depends on type): 0.4 - 0.6 [CS A03: 2013]
• Sand, wet : 1.9
• Sand, wet, packed: 2                           
• Sand, dry :1.6 [this figure is used in CS A03: 2013, page 11]
• Sand, loose :1.45

*UFL IFAS - http://hort.ifas.ufl.edu/woody/critical-value.shtml, last modified 27 Feb 2015, accessed on 11 Mar 2018.

CS A03: 2013 continues the note with "However in practice, while mixing the top soil for ASM, soil weight should be based on the moisture content of the soil". Does it mean that the moisture content of the sand and compost components should match the moisture content of the top soil before mixing?

Changes from CS A01:2009 and addition to CS A03: 2013
2.1 Soil Mix Specifications - Physical and Chemical Requirements, page 10 -> 2.1.3  Approved Soil Mix Specification, page 16

Changed values in C:N Ratio, Bulk Density, CEC, Pathogens
Added value in Moisture Content
Deleted Permeability, Heavy Metal Concentration, Organic Contaminants

Added section to CS A03: 2013
2.1.1    Top Soil Specifications - Physical and Chemical Requirements, page 12

Changes from CS A02:2009 and addition to CS A03: 2013
2.4    Physical and Chemical Requirements, page 10 -> 2.1.2    Compost Specifications - Physical and Chemical Requirements

Deleted column for "Mulch"
Added value for Bulk Density
Changed values for Particle Size, Foreign Matter / Physical Contaminents, Pest insects / Invertebrates

Added section in CS A03: 2013
2.1.2.1    Feedstocks for Composting, page 15

Changes from CS A01:2009 to CS A03: 2013
2.2 Soil Sampling, page 16 -> 2.2 Soil Sampling, page 11

Deletion of Definition of Landscape Management Unit and Site Analysis
Addition to Number of Samples within a Landscape Management Unit
Added Representative Sampling

Changes from CS A01:2009 to CS A03: 2013
2.5 Soil Mixing, page 18 -> 2.3 Soil Mixing, page 17

Deletion from CS A01:2009 to CS A03: 2013
2.6 Basic Tools, page 19

No change in CS A01:2009 to CS A03: 2013
Section 3 - Marking and Documentation -> Section 3 - Marking and Documentation

Not common in practice.

Deletion from CS A02:2009 to CS A03: 2013
2.2 Process Criteria, page 9
2.3 Storage and Protection, page 9
2.6 Product Sampling, page 11
2.7 Application in the field, page 12

Describes how composting should be done and how long it should be composted.
Describes how finished product (matured compost) should be protected from contamination.
Describes how representative samples should be collected.
Describes how compost is used as a soil organic amendment (component of soil mix) and mulch.

Gebiz Spiral Watch

Quotation No.: HDB000ETQ18000011 (Housing and Development Board)

QUOTATION FOR INTERNATIONAL SOCIETY OF ARBORICULTURE (ISA) CERTIFIED ARBORIST FOR CONSULTANCY SERVICES, SURVEYING & RECOMMENDATION FOR NPARKS SUBMISSION FOR THE DEMOLITION OF HDB RESIDENTIAL BLOCKS 1A, 2A, 3A, 4A, 5A & 6A AT WOODLANDS CENTRE ROAD

Company A - $4,948 (Awarded)
Company B - $18,000
Company C - $7
Company D - $20,800

Lowest bid is 99.8% lesser than second lowest bid.

But maybe there is confusion over the quantity, leading to one strange quote here.
Assuming there are 1000 nos trees, then the quote by Company C may be $7000. Using this assumption, then the following applies.

Lowest bid is 29.3% lesser than second lowest bid.
Highest bid is 4.2 times (420%) more than lowest bid.