predicted Canopy

Basic data

Programme name
Woodland tree costCost of planting a whip or feather en masse in a woodland setting	£
Urban tree costCost of planting a standard tree in an urban setting	£
Target hectaresOptional: Overall target for canopy increase in hectares by the end of the period of prediction
Base yearThe calender year at the start of prediction
Predict for Number of years ahead to predict	years

Name
Status To include or exclude the plan from the programmme	Include Exclude
Plan Type
Plan period	Start year Number of years
Hectares For woodland planting	hectares/annum
Spacing For woodland planting	m
Number of trees For individual trees, -ve for trees which have been lost	number/annum
Age at plantingAge of the tree when planted or when lost	years
Species Planted
Site
Radius increase Override species/site growth rate	mm/annum
Age at maturity Override species/site maturity	years
Life expectancy Override species life expectancy	years
DBH to Canopy model Calculate Canopy width from DBH

predicted Canopy

Summary

Prediction years	2026 to 2056
Results at	2057
Net trees planted	0
Final number of trees	0
Hectares planted	0.0
Final hectares	0.00
Breakeven year
Total cost	£0

Year	Total

Tree plans

A tree programme is defined by a number of overall parameters and one or more plans. Three kinds of plans are supported:

Woodland Planting

Trees are planted in an area with a given spacing between trees. Total canopy area is limited to the area planted.

Individual trees

Each tree can develop a full canopy, so the total area is the sum of the individual canopies.

Tree loss

Trees lost in one or slowly over a number or years..

The same plan can be undertaken for a number of years in succession.

Tree growth rate

The first step in modelling the growth of a tree requires the prediction of the Girth (circumference) or equivalently the Diameter at Breast height (DBH) over time. There have been a number of studies of the related problem, that of estimating the age of a tree given its girth. A commonly quoted rule is that trees put on an inch of girth per annum i.e. 4mm radius per annum.

In practice, growth rates depend on species and the site. One source of data is the paper by John White from the Forestry Commission Information Note FCIN12 "Estimating the Age of Large and Veteran Trees in Britain" In this model, the tree puts on rings of constant width up to the age of maturity, and then rings of constant area until senescence. This model is also used in our Tree Age Calculator

Another source which we have not yet integrated is this paper by a Veteran Tree Association

Ring radius /year in mm	Age at Maturity	DBH cm 5 years	DBH cm 25 years	DBH cm 100 years
2	25	2	10	26.23
2	50	2	10	34.53
2	100	2	10	40
3	25	3	15	39.34
3	50	3	15	51.79
3	100	3	15	60
4	25	4	20	52.46
4	50	4	20	69.05
4	100	4	20	80
5	25	5	25	65.57
5	50	5	25	86.31
5	100	5	25	100
6	25	6	30	78.69
6	50	6	30	103.58
6	100	6	30	120
7	25	7	35	91.8
7	50	7	35	120.84
7	100	7	35	140

Lifespan and mortality

Trees have lifespans which depend on a number of factors: species, situation, climate and diseases. Data on the expected lifespan of tree species is sparse and for urban trees even sparser. The table below shows some typical values. To compute the effect of limited lifespan on both the lost tree and the replacement trees, this age is used to compute the mortality of the tree, based on the assumption that annual mortality is constant throughout the life of the tree and that the lifespan represents the actuarial life expectancy = -1/ln(1-mortality). No adjustment is yet made location. Mortality of urban trees, especially in the early, vulnerable years is quite high as the paper by Lara Roman et al shows, where mortality is estimated to be between 3.5 and 5% / annum. The planting site has a particular influence on mortality, with small tree-pits containing structural soil reducing lifespan to 12-15 years.

Lifespan of tree species

This table shows data from Hellis .

Species	Common name	Lifespan	Source
Acer campestre	Field Maple	200	Hellis
Acer platanoides	Norway Maple	150	Hellis
Acer pseudoplatanus	Sycamore	220	Hellis
Acer saccharinum	Silver Maple	150	Hellis
Aesculus hippocastanum	Horse Chestnut	350	Hellis
Ailanthus altissima	Tree of Heaven	200	Hellis
Alnus glutinosa	Common Alder	200	Hellis
Araucaria araucana	Monkey Puzzle	150	Hellis
Betula pendula	Silver Birch	80	Hellis
Carpinus betulus	Hornbeam	300	Hellis
Castanea sativa	Sweet Chestnut	450	Hellis
Catalpa bignoides	Indian Bean Tree	150	Hellis
Cedrus libani	Cedar of Lebanon	350	Hellis
Corylus avellana	Hazel	70	Hellis
Eucalyptus gunnii	Cider Gum Eucalyptus	120	Hellis
Fagus	Beech	200	Hellis
Fraxinus	Ash	200	Hellis
Ginkgo biloba	Ginkgo	250	Hellis
Ilex aquifolium	Holly	120	Hellis
Juglans regia	Walnut	200	Hellis
Larix decidua	European Larch	350	Hellis
Liriodendron tulipifera	Tulip Tree	300	Hellis
Malus	Apple	80	Hellis
Morus nigra	Mulberry	150	Hellis
Nyassa sylvatica	Tupelo	220	Hellis
Picea abies	Norway Spruce	200	Hellis
Pinus pinaster	Maritime Pine	180	Hellis
Pinus sylvestris	Scots Pine	300	Hellis
Platanus x acerifolia	London Plane	400	Hellis
Populus nigra ‘Italica’	Lombardy Poplar	150	Hellis
Populus tremula	Aspen	100	Hellis
Prunus avium	Wild Cherry	150	Hellis
Quercus cocinea	Scarlet Oak	150	Hellis
Quercus rubra	Red Oak	200	Hellis
Quercus rubur	English Oak	350	Hellis
Robinia pseudacacia	Robinia	250	Hellis
Salix fragilis	Crack Willow	100	Hellis
Sorbus aucuparia	Rowan	120	Hellis
Taxus baccata	Yew	400	Hellis
Tilia x europaea	Common Lime	400	Hellis
Ulmus	English Elm	100	Hellis
Ulmus glabra	Wych Elm	250	Hellis

DBH (Diameter at Breast Height) to Canopy

Tree canopy is typically measured by the area as seen from above. For a single tree, this can be measured on the ground by measuring the distance from the trunk to the outer edge at the 4 directions north, south, east and west to find an average radius. Measuring the canopy across an area is more dfficult and several approaches can be used. Our mapping of Canopy area in Bristol uses the i-Tree Canopy method.

Canopy area can be estimated from the DBH in a number of ways.

RPA (Root Protection Area)

Biodiversity Net Gain Calculator 3.1 uses BS 5837 : Trees in relation to design, demolition and construcion - Recommendations. to calculate the habitat area of an urban tree. It is a species-independent method which uses the Root Protection Area (RPA) of a tree as a proxy for its habitat value (effectively canopy). This method calculates RPA radius as 12 * DBH to calculate the RPA in metres.

Allometric modelling

In practice, canopy area will depend on the tree shape and hence the species. The table below shows typical values of the parameters found in research reports and our own analysis of Bristol's urban trees.

Species	a	b	Canopy Area m^2 5cm	Canopy Area m^2 25cm	Canopy Area m^2 50cm	Canopy Area m^2 100cm	Source
BS 5835			1	28	113	452
Abies alba	-0.14	0.4239	9	36	65	118	Pretzch
Abies sachalinensis	-1.10	0.6894	3	29	77	199	Pretzch
Acer campestre	-1.332	0.777	3	33	96	281	BTF
Acer campestre	-0.36	0.45	7	28	52	96	Montiero
Acer negundo	-1.428	0.802	2	32	96	292	BTF
Acer platanoides	-1.232	0.757	3	35	100	285	BTF
Acer platanoides 'Crimson King'	-1.054	0.719	4	39	106	287	BTF
Acer pseudoplatanus	-1.003	0.683	4	34	88	228	BTF
Acer pseudoplatanus	-0.44	0.5339	7	41	85	178	Pretzch
Acer pseudoplatanus 'Purpureum'	-1.494	0.842	2	36	115	369	BTF
Acer saccharinum	-1.005	0.713	4	41	111	299	BTF
Aesculus hippocastanum	-1.188	0.702	3	27	71	188	BTF
Aesculus hippocastanum	-0.55	0.6011	7	50	115	265	Pretzch
Aesculus x carnea	-1.278	0.748	3	30	85	239	BTF
Alnus cordata	-1.12	0.716	3	34	91	245	BTF
Alnus glutinosa	-1.661	0.87	2	31	102	342	BTF
Alnus incana	-1.235	0.742	3	32	88	247	BTF
Alnus nigra	-0.86	0.6507	5	37	91	225	Pretzch
Araucaria cunninghamii	-0.68	0.3899	3	10	17	29	Pretzch
Average species	-0.7129	0.6049	5	37	86	198	Pretzch
Betula pendula	-1.205	0.762	3	38	110	315	BTF
Betula pendula	-0.97	0.6483	4	29	72	177	Pretzch
Betula pendula	-0.4	0.75	16	176	499	1412	Montiero
Betula utilis var. jacquemontii	-1.197	0.808	4	52	160	489	BTF
Buxus sempervirens	0.319	0.336	18	52	82	131	BTF
Carpinus betulus	-1.418	0.804	2	33	99	303	BTF
Carpinus betulus	-0.1744	0.5470	13	75	160	342	Pretzch
Carpinus betulus 'Fastigiata'	-1.728	0.874	2	28	92	311	BTF
Castanea sativa	-1.111	0.68	3	27	70	179	BTF
Cedrus libani	-1.556	0.769	2	20	57	167	BTF
Chamaecyparis lawsoniana	-1.191	0.641	2	18	44	106	BTF
Corylus avellana	0.207	0.288	12	30	45	67	BTF
Corylus colurna	-1.943	0.97	1	33	127	489	BTF
Crataegus monogyna	-0.791	0.501	3	16	33	65	BTF
Crataegus x persimilis 'Prunifolia'	-0.666	0.58	5	35	78	173	BTF
Cupressus macrocarpa	-0.807	0.595	4	29	66	150	BTF
Cupressus x leylandii	-0.719	0.516	4	21	42	86	BTF
Fagus sylvatica	-1.315	0.759	3	30	86	246	BTF
Fagus sylvatica	0.01	0.4710	15	66	128	245	Pretzch
Fagus sylvatica	-0.26	0.68	17	149	382	980	Montiero
Fagus sylvatica 'Purpurea'	-0.92	0.69	5	42	110	287	BTF
Fraxinus angustifolia	-1.055	0.733	4	43	118	326	BTF
Fraxinus excelsior	-1.211	0.752	3	35	100	284	BTF
Fraxinus excelsior	-0.81	0.6052	4	31	71	164	Pretzch
Fraxinus excelsior	-0.34	0.77	19	226	658	1914	Montiero
Fraxinus excelsior	-0.3	0.64	14	106	258	626	Montiero
Ginkgo biloba	-1.446	0.795	2	29	88	264	BTF
Ilex aquifolium	-0.045	0.313	8	22	33	51	BTF
Juglans regia	-1.485	0.84	2	36	115	369	BTF
Khaya senegalensis	-0.59	0.6461	8	62	151	371	Pretzch
Larix decidua	-1.287	0.769	3	34	98	285	BTF
Larix decidua	-1.29	0.7131	2	23	63	169	Pretzch
Liquidambar styraciflua	-1.851	0.977	2	42	162	627	BTF
Liriodendron tulipifera	-1.212	0.739	3	32	90	251	BTF
Malus trilobata	-1.51	0.77	2	22	63	184	BTF
Malus tschonoskii	-1.305	0.71	2	22	60	160	BTF
Metasequoia glyptostroboides	-1.361	0.696	2	18	48	126	BTF
Picea abies	-0.56	0.505	5	26	53	107	BTF
Picea abies	-0.67	0.5083	4	22	44	89	Pretzch
Picea glauca	-1.79	0.8276	1	18	57	179	Pretzch
Pinus nigra	-1.158	0.696	3	27	72	189	BTF
Pinus nigra subsp. laricio	-1.076	0.697	3	32	85	224	BTF
Pinus nigra subsp. nigra	-1.065	0.692	3	32	84	219	BTF
Pinus sylvestris	-1.426	0.744	2	22	61	172	BTF
Pinus sylvestris	-1.03	0.6381	3	24	59	143	Pretzch
Platanus x acerifolia	-0.756	0.643	5	43	106	259	BTF
Platanus × hispanica	-0.55	0.6532	9	70	173	429	Pretzch
Populus alba	-1.019	0.684	4	33	86	223	BTF
Populus nigra	-0.403	0.534	8	44	92	192	BTF
Populus nigra 'Italica'	-0.766	0.493	3	16	32	64	BTF
Populus x canadensis 'Robusta'	-0.815	0.656	5	42	104	259	BTF
Prunus avium	-1.285	0.781	3	37	108	320	BTF
Prunus avium 'Plena'	-1.651	0.925	2	45	161	580	BTF
Prunus cerasifera	-0.593	0.553	6	34	73	156	BTF
Prunus cerasifera 'Pissardii'	-0.843	0.6	4	28	64	146	BTF
Prunus domestica	-0.767	0.593	5	31	70	160	BTF
Prunus lusitanica	0.584	0.168	17	30	38	47	BTF
Prunus padus	-0.704	0.612	6	40	92	216	BTF
Prunus serrulata 'Amanogawa'	-1.107	0.658	3	24	59	147	BTF
Pseudotsuga menziesii	-1.416	0.802	2	32	98	299	BTF
Pseudotsuga menziesii	-1.28	0.7522	3	31	87	248	Pretzch
Pyrus calleryana 'Chanticleer'	-1.683	0.837	2	24	76	242	BTF
Quercus cerris	-1.394	0.805	3	34	105	321	BTF
Quercus ilex	-1.095	0.707	3	33	89	237	BTF
Quercus petraea	-1.756	0.951	2	43	160	597	BTF
Quercus robur	-1.21	0.727	3	30	83	226	BTF
Quercus robur	-1.44	0.8157	2	34	104	323	Pretzch
Quercus robur	-0.42	0.62	10	73	173	410	Montiero
Quercus rubra	-0.898	0.654	4	35	87	215	BTF
Robinia pseudoacacia	-0.814	0.632	5	36	87	208	BTF
Robinia pseudoacacia	-0.43	0.5822	9	56	126	283	Pretzch
Salix alba	-0.689	0.599	5	37	86	197	BTF
Salix caprea	-0.18	0.419	8	33	58	104	BTF
Salix fragilis	-0.413	0.528	8	41	86	178	BTF
Salix x sepulcralis 'Chrysocoma'	-0.691	0.613	6	41	95	223	BTF
Sambucus nigra	0.472	0.13	12	19	22	27	BTF
Sorbus aria	-1.445	0.796	2	29	88	267	BTF
Sorbus aucuparia	-1.023	0.665	3	29	74	186	BTF
Sorbus aucuparia	-0.35	0.4621	7	31	58	110	Pretzch
Sorbus intermedia	-1.306	0.734	2	26	72	199	BTF
Taxus baccata	-0.087	0.412	10	37	66	117	BTF
Taxus baccata 'Fastigiata'	-0.704	0.444	3	13	25	46	BTF
Thuja plicata	-0.493	0.441	5	20	37	68	BTF
Tilia cordata	-1.551	0.835	2	31	97	309	BTF
Tilia cordata	-0.34	0.5728	10	64	141	311	Pretzch
Tilia cordata 'Greenspire'	-1.631	0.938	2	50	185	680	BTF
Tilia platyphyllos	-1.17	0.756	3	39	112	320	BTF
Tilia x euchlora	-0.825	0.665	5	44	110	276	BTF
Tilia x europaea	-1.189	0.692	3	25	65	171	BTF
Ulmus glabra	-1.05	0.733	4	43	119	329	BTF
Ulmus glabra	-0.21	0.5763	13	84	187	417	Pretzch

Reference

BTF : fitted from BCC records
Pretzch : Crown size and growing space requirement of common tree species in urban centres, parks, and forests by Pretzch et al (2015)
Montiero : Growth rates of common urban trees in five cities in Great Britain: A dendrochronological evaluation with an emphasis on the impact of climate (2017)

Trees of Bristol Canopy prediction

Prediction URL

predicted Canopy

predicted Canopy

Summary

Tree plans

Woodland Planting

Individual trees

Tree loss

Tree growth rate

Lifespan and mortality

Lifespan of tree species

DBH (Diameter at Breast Height) to Canopy

RPA (Root Protection Area)

Allometric modelling

Reference

Trees of Bristol Canopy prediction

Programme Summary Prediction Data Prediction Chart About Full structure Prediction URL

predicted Canopy

predicted Canopy

Summary

Tree plans

Woodland Planting

Individual trees

Tree loss

Tree growth rate

Species table

The inverse: Age and Radius table

Lifespan and mortality

Lifespan of tree species Show

DBH (Diameter at Breast Height) to Canopy

RPA (Root Protection Area)

Allometric modelling

Allometric coefficients for estimating Canopy radius from DBH

Reference

Prediction URL

Lifespan of tree species