General
Most conifers are graded to heights appropriate for their age and development.
The following tables indicates the typical grades.
The overall height grades are different for the four root conditions in which conifers are supplied: bare root; cell grown; rootballed; container grown.
Bare Root
Figure 1: 1+2, TRANSPLANT
Many conifers do not transplant well bare root when older than 3 years. Older than this most conifers should be supplied root balled or container grown. For seedling and transplant conifers, up to three years old, the following overall height grades apply.
Height grades : Forestry seedlings and transplants
| cm |
Form |
| 10-15 |
Seedling |
| 15-20 |
Seedling |
| 20-25 |
Seedling |
| 25-30 |
Undercut seedling/Transplant |
| 30-40 |
Undercut seedling/Transplant |
| 40-50 |
Transplant |
| 50-60 |
Transplant |
| 60-80 |
Transplant |
e.g.
Pinus sylvestris
Pinus nigra
Picea abies
Picea sitchensis
Tsuga heterophylla
Cell Grown
Figure 2: CELL GROWN
(Pinus sylvestris, 100 cc cell,
20-40 cm height)
Height grades : Cell grown conifer seedlings
| cm |
Form |
| 10-20 |
Seedling |
| 15-30 |
Seedling |
| 20-40 |
Seedling |
| 40-60 |
Seedling |
e.g.
Pinus nigra
Pinus sylvestris
Picea abies
Picea sitchensis
Rootballed
Height or spread grades : Dwarf/bushy types
| cm |
|
|
cm |
|
|
cm |
|
| 12-15 |
|
40-50 |
blue |
|
90-100 |
blue |
| 15-20 |
blue |
50-60 |
yellow |
|
100-125 |
white |
| 20-25 |
yellow |
60-70 |
red |
|
125-150 |
blue |
| 25-30 |
red |
70-80 |
white |
|
150-175 |
red |
| 30-40 |
white |
80-90 |
yellow |
|
175-200 |
yellow |
| above 200 in 50 cm. steps. |
e.g.
Chamaecyparis obtusa 'Nana Gracilis'
Juniperus squamata 'Blue Star'
Picea glauca 'Alberta Globe'
Pinus mugo pumilio
The colours indicate the internationally accepted marking system for the height/spread grades
Height grades : Upright growing: medium
Figure 3: ROOTBALLED CONIFER
(Taxus baccata, 100-125)
cm |
|
cm |
|
cm |
|
30-40 |
white |
80-90 |
yellow |
175-200 |
yellow |
40-50 |
blue |
90-100 |
blue |
200-225 |
blue |
50-60 |
yellow |
100-125 |
white |
225-250 |
white |
60-70 |
red |
125-150 |
blue
|
250-275 |
yellow |
70-80 |
white
|
150-175
|
red |
275-300 |
red |
e.g. Chamaecyparis lawsoniana ‘Ellwoodii’, Pinus mugo, Thuja occidentalis ‘Rheingold’, Taxus baccata ‘Fastigiata’
The colours indicate the internationally accepted marking system for the height/spread grades.
Height grades : Upright growing: vigorous
Figure 4: ROOTBALLED CONIFER
(Chamaecyparis lawsoniana
'Columnaris', 150-175 cm)
cm |
|
cm |
|
cm |
|
40-60 |
blue |
100-125 |
white |
200-250 |
blue |
50-60 |
yellow |
125-150 |
blue |
250-300 |
yellow |
60-80 |
red |
150-175 |
red |
300-350 |
blue |
80-100
|
yellow |
175-200 |
yellow |
350-400 |
white |
e.g. Cedrus libani, Chamaecyparis lawsoniana, x Cupressocyparis leylandii, Thuja plicata + cvs.
The colours indicate the internationally accepted marking system for the height/spread grades.
Specimen conifers: The OVERALL HEIGHT and SPREAD is specified.
For species/cvs. With a vigorous growing top leading shoot, half of the annual top shoot is the upper limit for the measure of the height e.g. Pseudotsuga spp, Picea omorika.
Container Grown
Height and Spread grades : Dwarf/prostrate types
Figure 5: CONTAINER GROWN CONIFER
(Juniperus communis 'Compressa', 5 litre)
| cm |
e.g. |
| 15-20 |
Chamaecyparis spp.
Juniperus spp.
Picea spp.
Tsuga spp. |
| 20-30 |
| 30-40 |
Height and Spread grades : Medium and vigorous types
| cm |
e.g. |
| 20-30 |
Abies spp.
Cedrus spp.
Chamaecyparis spp.
x Cupressocyparis spp.
Juniperus spp. |
| 40-50 |
| 50-60 |
| 60-70 |
For species/cvs. with a vigorous growing top leading shoot, half of the annual top shoot is the upper limit for the measure of the height. e.g. Pseudotsuga, Picea omorika.