BTF Comments – 04 December 2024

2

Broad Heathland and shrub habitats are identified in the UKHab as a category of h3 Dense

scrub, which is defined as ‘patches of shrubs that are <5 m in height with continuous (> 75%)

cover.’ h3h Mixed scrub is defined as ‘comprising a mixture of species without a single species

dominant or stands with dominant species not listed in h3a-h3k.’2

The applicant’s arboricultural evidence identifies three tree features growing along the edge

of the canal:3

Tree

Number

Tree

Count Tree Species Scientific Name

Height

(m)

Number

of Stems

Stem Ø

(cm)

T1 1 Goat willow Salix caprea 4.5 MS 21

T2 1 Goat willow Salix caprea 6 MS 83

G1 14 Dogwood, holm oak

and buddleia Various 5 MS 13

While tree T1 might be designated as Mixed scrub habitat, because it is only 4.5 metres high,

the applicant has chosen to designate it and T2 as Individual trees habitat.

However, the applicant has designated tree group G1 as Mixed scrub habitat. This is incorrect

because it does not meet the UKHab definition – it is not less than 5 metres high. It is Urban -

Individual trees habitat. On this basis these three trees have a habitat area of 0.0977 ha.

We have reduced the baseline Mixed scrub habitat area by 35% to 0.013845 ha in light of this,

though this causes a small mismatch between the combined ground-based pre and post-

development habitat area that will need to be adjusted.

Strategic Significance

Urban trees are given express protection under the local Plan – BCS9 and SADMP DM17. On this

basis we have assigned both these baseline and post-development habitats as having high

strategic significance.

Individual trees habitat creation

The applicant will plant ‘approximately’ small BNG category 26 trees in the post-development

phase. The arboricultural evidence states that 18 trees will be planted at ground level and a

further eight trees on the root terrace. We assume that these will be in some sort of planter.

Trees in planters should not be designated as Individual trees habitat. Instead, they should be

classified these as part of the Urban Ground level planters habitat though, of course, they

would not be on the ground. We have excluded these eight trees to be planted on the roof in

our Individual trees habitat calculation, though we accept they should be given some sort of

habitat value.

2 UKhab Ltd (2023). UK Habitat Classification version 2.0 - https://ukhab.org/. 3 24_04568_F-ARBORICULTURAL_IMPACT_ASSESSMENT_AND_TREE_PROTECTION_PLAN-3805204

BTF Comments – 04 December 2024

3

The post-development habitat creation delay

There is going to be a delay between the baseline habitats being removed – we assume in the

demolition phase – and the new habitats being created so have factored in a two-year delay for

habitat creation.

The net gain calculation

On the basis of the changes set out above, we calculate that there will be a net loss of area

biodiversity of 20.33%, with a shortfall of 0.31 habitats on the assumption that a 10% net gain

target has been used.

In addition, there is a breach of the trading rules caused by a shortfall of 0.66 habitat units of

Individual trees habitat. This will also need to be addressed.

BTRS

We calculate that 14 replacement trees will be required under SADMP DM17 and the Bristol

Tree Replacement Scheme SPD (BTRS) to replace the 14 trees that make up tree group G1.

However, as the applicant plans to plan more than 14 on site, no offsite compensation will be

necessary.