Belfast trees

I was poking around the Open Data NI website this evening when I stumbled across the Belfast trees dataset. The dataset provides a location for each of 37,557 trees in the city (as of November 2015) plus its species, health and diameter. There’s a nice tree map here but I thought I might practice my R mapping skills for a bit of fun. Where are Belfast’s most unusual trees?

First off, there are 53 different species of tree on the list, of which the six most frequent are:

Species Trees
Lime 6370
Maple 5423
Ash 2346
Oak 2259
Pine 2178
Cherry 1690

The bottom of the list is just as interesting. Our six least common trees are:

Species Trees
Magnolia 5
Plum 4
Tree Of Heaven 4
Liquidamber 2
Handkerchief 1
Rauli 1

What is a ‘Handkerchief Tree’? Rather lovely it turns out. Where is Belfast’s sole handkerchief tree? Turns out it’s in the Sir Thomas and Lady Dixon Park (red icon below). (The sole Rauli tree is in Belfast Zoo).

Finally, Belfast’s thickest tree (by trunk diameter) is in Belfast City Cemetery on the Falls Road and its tallest tree is in Cherryvale park, off the Ravenhill road. See the orange icons in the map below.

Finally, out of curiosity, where are Belfast’s sickest street trees? That is, as opposed to trees in parks. The map below contains street trees that are classed as low vigour and are either classed as being in poor condition or very poor condition or dying:

523 street trees in Belfast meet both these conditions. While street trees are clustered in general there do seem to be some streets with a lot of sick trees. Illness clusters too I imagine. In terms of species, we should perhaps worry about Belfast’s few Hawthorn bushes, but I can’t see a good pattern. A bit more digging might help (or not)…

Species Total Healthy Sick Sick %
Hawthorn 25 20 5 20
Chestnut 85 75 10 11
Poplar 38 34 4 10
Rowan 416 377 39 9
Apple 12 11 1 8
Beech 32 30 2 6
Crab Apple 37 35 2 5
Lime 5025 4739 286 5
Hazel 414 395 19 4
Maple 1083 1036 47 4
Cherry 818 791 27 3
Hornbeam 789 764 25 3
Oak 159 154 5 3
Ash 167 163 4 2
Birch 183 178 5 2

Gist with code here.

Ciarán O'Kelly
Ciarán O'Kelly
Senior Lecturer, School of Law

My research interests include corporate governance, law and technology and business language on human rights.