Bs rating, I'm confused now...

[Thehardwaremonkey]

I don't know if I'm being treated as an idiot or not -help!

 

I have a single eucalyptus cider gum tree in my garden, it's stem is 510 in radius at 1.5m height, approx 12m tall and in a healthy state. Which makes an RP radius of about 6 metres(?).

The tree is on my land and close to a neighbouring development, so has been given a bs5837 rating of C3 by them/their report for the following reasons, is this correct, does lack of biodiversity make it a C3 tree always as a Eucalyptus?

 

Their response to me when I queried the category...;

With regards to the categorisation of the tree, this decision was made

following an appraisal of the tree, the species and its location.

Eucalyptus offer no foraging value to our native invertebrates and are of

little value to local biodiversity therefore the tree does not have the

'material or other cultural value' that would require it to be categorised

as a 'B'. Eucalyptus as a species are also particularly vulnerable to wind

throw which will direct future management in the future and limit its

wider amenity value.

[benedmonds]

I don't know if I'm being treated as an idiot or not -help!

The tree is on my land and close to a neighbouring development, so has been given a bs5837 rating of C3

 

If the tree is "unremarkable" I would probably of categorised it as a C. However this makes no difference to the level of protection it should receive if it is being retained.

 

Eucalyptus as a species are also particularly vulnerable to wind

throw which will direct future management in the future and limit its

wider amenity value.

 

I don't agree with this statement however..

[chrism3513]

especially as Eucalyptus is a genus not a species.

 

what do they mean by wind throw?

[Chris at eden]

If the tree is "unremarkable" I would probably of categorised it as a C. However this makes no difference to the level of protection it should receive if it is being retained.

 

 

 

I don't agree with this statement however..

 

 

I would agree with both of Ben's statements. I can't see why you would use subcategory 3 either for a Eucalyptus as its never likely to fit. C1 or C2 is more likely in my opinion.

 

Eucalyptus bend and sway a lot in the wind which is a process known as mass damping. This effectively dissipates dynamic energy gradually over the whole tree rather than point loading a specific area. This would be more likely to reduce the risk of windthrow as long as there are no associated defects.

[Paul Barton]

If it's 12 metres tall and in a healthy state, the chances are it may be a 'moderate' value tree (i.e. B category) rather than 'poor' ©. Either way, the developer needs to ensure that they don't damage your tree during construction.

 

If I were you I would take regular photos of the tree now, during construction and for a few seasons afterwards. If the tree dies because of root damage over the boundary then you'll want to be able to provide some evidence of its demise.

[Chris at eden]

especially as Eucalyptus is a genus not a species.

 

what do they mean by wind throw?

 

Picky but good point. I doubt it would get you far with the PINS inspector.

 

Eucalyptus gunnii or cider gum is the species. i.e. the full name.

 

What people usually refer to as the species (i.e. gunnii) is actually correctly termed the specific epithet.

 

 

Windthrow is failure from the rootplate during storms.

 

Cheers

[Thehardwaremonkey]

Wow, thanks so much for sharing your specialist knowledge on this so quickly, I love the quote that it is a Genus not a species

I've been googling and trying to get up to speed on the topic for hours/days now, so thanks a million.

I was worried that my tree had been 'set up for a fall' by getting a C3 rating, so I appreciate the feedback that it will/should still receive protection... Had they not of already dug the footings before planning consent

I really struggled with the difference between a B and a C, I appreciate its no way near an A. It is a beautiful tree, I did not plant it, so believe it's around 15+ years old and smells and sounds amazing in the wind.

I also could not find anything that suggested this tree type was more susceptible to windthrow.... if you don't dig a big hole in its RP area...

I will request planning to take it from here now I am reassured I'm not just a weird tree hugger that 'knows nothing' - THANKS so much folks, I will report back

[Thehardwaremonkey]

I meant to insert this.

 

I'm not sure how well this will paste; this was the details of the tree, to be fair they would have had to guess the diameter but I have measured it at 509.

(Off site) T6

cider gum, Eucalyptus gunnii)

Height (M) 12

Stem diameter at 1.5m 400mm

Branch spread: North 3m East 4m South 3m West 3m

2.5m

Age: Mature

Physiological condition: Good

Structural conditions: S a t i s f ac t or y .

Preliminary management: one

20+

C3

[Chris at eden]

I meant to insert this.

 

I'm not sure how well this will paste; this was the details of the tree, to be fair they would have had to guess the diameter but I have measured it at 509.

(Off site) T6

cider gum, Eucalyptus gunnii)

Height (M) 12

Stem diameter at 1.5m 400mm

Branch spread: North 3m East 4m South 3m West 3m

2.5m

Age: Mature

Physiological condition: Good

Structural conditions: S a t i s f ac t or y .

Preliminary management: one

20+

C3

 

There is no height of first branch and direction or canopy clearance which are very important.

 

The P and S condition fields are more in accordance with the 2005 standard, they tend to be grouped together under general observations now. Not a big deal though.

 

Writing satisfactory for structural condition is a cop out as it would indicate that the tree has some defects that can be remediated but give no details. These should be identified in detail in my opinion. e.g. cavity, fungal fruiting bodies, deadwood, over extended branches, weak forks, etc.

 

It would be interesting to see what was written for the impact assessment. In my experience most of these 5837 reports make no attempt to even identify impacts never mind evaluate or mitigate them.

[Chris at eden]

I was worried that my tree had been 'set up for a fall' by getting a C3 rating, so I appreciate the feedback that it will/should still receive protection... Had they not of already dug the footings before planning consent

 

It may have unfortunately. If they have already dug the footings and damaged the tree then it may need to be felled on safety grounds. I doubt that the council will see this as a planning consideration (unless its protected) so any loss you experience is likely to only be addressed as a civil claim. Even then they have a common law right to cut back the over hang which includes the roots so not straight forward.

[daltontrees]

The C3 categorisation is a nonsense, the surveyor is busted and his/her retrospective justification is equally nonsense. If the tree really is in good condition and with reasonable management will continue in existence for several decades, tehre is no reason for it being anything other than A or B.

 

But that's not teh real issue. Why on earth has 3 been chosen? If it's in a garden it shoud probably be a 1 (Arboricultural value). So I'd say A1 or B1. You could hardly get further away from that than C3. And you'd only get there if you were trying to justify unfettered damage and to create development value.

 

Eve by teh survey desctiption it has to be at least B. Even if it's in a Conservation Area, a 1 value would trump a 3 value.

 

Maybe write to the Council and make sure the planners know (if they don't already) that this categorisation is farcical.