Dormant Service Tree
aka Sorb-Apple, True Service Tree, not to be confused with Wild Service Tree (Cornus domestica) and Service Berry (Amelanchier spp.)
Unspecified (pear form)
Description and site preference
Type and size – large tree, 45-60 feet if not pruned
Hardiness zone – 4-8
Exposure – full- to half-day sun
Soil – wide range
Drainage – well-drained
Years to harvest –2-3 (Carandale Farm did not harvest for up to 6 years)
Maintenance – minimal, except pruning
Life of planting – 100 years or more
Machine harvest potential – none
Suitable markets – unknown
Nutritional highlights – unknown
Adaptability – high
Pest issues – few (could be subject to fire blight)
Invasive potential – minimal
Environmental benefits – may be a good dynamic accumulator
Shared management – intermediate, similar to most other fruit trees
Shared equipment – pruning
Shared processing – low, with specialized needs
Co-marketing – low, specialty marketing for local sales
Low economic potential as a companion crop, though it would add ecological diversity.
History and background
Service tree is a species of Sorbus native to western, central and southern Europe, northwest Africa and southwest Asia. Known to live 300-400 years in parts of Britain, the tree typically grows 45-60 feet if not pruned. Self-fertile flowers are produced on cymes and pollinated by insects. The fruit is a pome about an inch long and can be either apple- or pear-shaped.
Picked straight off the tree, the fruit is said to be astringent, but it becomes sweet, soft and aromatic if properly bletted (an over-ripening process), with the taste of spiced pears. There is little known about its uses or nutritional profile.
Observations at Carandale Farm
Carandale Farm ordered the pear form of service tree from Northwoods Nursery (see One Green World) in 2006 for their trial.
- Trials showed no sign of disease or insect damage in six years since establishment.
- Plants are winter hardy and showed no sign of winter damage.
- The catalog description said they should bear fruit in 2-3 years, but no fruiting has occurred in the six years they have been in the Carandale test plot.
- The trees are healthy, vigorous and have a strong, semi-upright branching pattern.
The trees have shown impressive adaptability and insect and disease resistance during the six years they have been in the Carandale test plot. With no fruiting to observe, the potential of service tree as a fruit crop could not be determined.
Even if the fruit is proven to be enjoyable for fresh consumption after bletting, the fruit will be soft and difficult to transport. Sales will probably be limited to local retail. Service tree’s potential for processing is yet to be determined. As a tree fruit, mechanical harvesting will probably not be an option. Carandale will continue to observe it in the test plot until it produces fruit and a more definitive evaluation can be made.
Wikipedia entry on Service Tree