Table of Contents
Mazza, G. and C.G. Davidson. 1993. Saskatoon berry: A fruit crop for the
prairies. p. 516-519. In: J. Janick and J.E. Simon (eds.), New crops. Wiley,
Saskatoon Berry: A Fruit Crop for the Prairies
G. Mazza and C.G. Davidson
- Irrigation and Fertility
- Weed Control
- FRUIT COMPOSITION
- Table 1
- Table 2
- Fig. 1
- Fig. 2
The saskatoon (Amelanchier alnifolia Nutt., Rosaceae) is a fruit bearing
shrub native to the southern Yukon and Northwest Territories, the Canadian
prairies and the northern plains of the United States (Harris 1972). It is
extremely adaptable and grows under a wide range of environmental conditions.
Saskatoon plants begin to bear fruit when they are two to four years old and
with proper management can yield 8 to 10 tonnes of fruit per hectare (Harris
1972; St. Pierre 1991). The fruit, usually called a berry, is actually a pome.
Saskatoon berries were originally used as a major food source by the native
people and early settlers of the North American prairies and, until recently,
could be picked only in the wild (Harris 1972). In the past two decades,
however, there has been increasing interest in utilizing this berry as a unique
western Canadian fruit crop. Today, there are 100 to 200 ha of saskatoons on
the Canadian prairies in production and 200 to 400 ha planted but still too
young to produce significant quantities. Many of the most profitable orchards
are near urban centers where a pick-your-own system is used to harvest and
market the berries. Plants have access to irrigation and are grown under
favorable environmental conditions to ensure high fruit yield and quality.
Many cultivars have been named by horticulturists over the years. These have
been primarily chance seedlings that have been selected for superior plant
and/or fruit characteristics. Currently, 'Smoky' is recommended for production
of good quality, medium-sized fruit, and 'Honeywood' for large fruit of fair
quality. Other cultivars include: 'Forestburg', 'Moonlake', 'Northline',
'Parkhill', 'Regent', 'Success', 'Porter', 'Thiessen', 'Altaglow', and
'Sturgeon'. 'Smoky', the most widely grown cultivar, has medium-sized, fleshy,
round, sweet, mild-flavored fruit growing in clusters (Fig. 1). Selected
physico-chemical characteristics of five cultivars are listed in Table 1.
Saskatoons can be propagated from seed, divisions, root cuttings, softwood
cuttings, and cuttings from etiolated shoots (Nelson 1987). In vitro
propagation of 'Northline', 'Pembina', 'Smoky', and 'Thiessen' saskatoon
berries has been reported (Harris 1980; Pruski et al. 1990). However, rooting
and post-rooting dormancy remains a problem for some cultivars. Growing
saskatoons from seed is relatively simple, but plants grown from seed differ
from parent in size and fruit characteristics (Davidson and Mazza 1991).
A comparison of plantings in sandy loam vs clay loam indicates much better
success in the former. A slight slope to provide for both air and water
drainage is also important. This is in agreement with the natural habitat of
the saskatoon which is often found in sandy and other well drained locales.
Row planting in contrast to spaced single plants has led to the best plant
establishment and growth. Rows planted 3.5 to 4 m apart with plants 1 m within
rows led to a high plant population with abundant in-row suckering. Over the
row mechanical harvesters require a minimum of 5 m, while pull-type harvesters
require 6 m spacing.
Irrigation under normally dry prairie conditions is essential for plant
establishment, and to maximize growth and fruit yield. Both trickle and
overhead irrigation systems are acceptable. While trickle irrigation is
generally more economical and efficient, particularly with wide row spacing,
overhead irrigation can provide frost protection and crop cooling. While
fertility requirements have not been investigated, fall applications are not
recommended since these may reduce winter-hardiness of plants.
Row cultivation can give relatively easy weed control if long rows are used at
a spacing which enables use of various size cultivators as the planting grows.
Currently, only the herbicide linuron is registered for use in saskatoon
production in Canada. On an experimental basis, pre-plant incorporated
trifluralin at 2.2 to 4.4 kg ai/ha provided excellent control of weeds at
planting. Post-plant dormant application of linuron has provided nearly full
season control of annual grasses and broad leafed weeds. Fall application is
preferred. Spring application must be made prior to budbreak and must be
followed by rain or irrigation.
Saskatoon plants begin to bear fruit when they are 2 to 4 years old. The fruit
is produced on the previous year's growth and on older wood. Usually young,
vigorous branches yield the highest quality fruit. Pruning should be done in
early spring after the danger of severe cold weather is past and before the
plants start to grow. Removal of all weak, diseased, damaged and low branches
as well as thinning of the center growth to keep it open is recommended.
Generally, major pruning is not required until the plants are 6 to 8 years old.
A number of insects and diseases can damage the plants and fruit. Important
insects that feed on flower buds, flowers, and fruit include lygus
(Lygus sp.), saskatoon budmoth (Epinota bicordana), saskatoon
sawfly (Hoplocampa montanicola), apple curculio (Anthonomas
quadrigibbus), and a leaf rolling caterpillar (Argyrotaenia
quadrifasciana) (St. Pierre 1989, 1991). In Canada, only deltamethrim
(Decis) is registered for use, and it is effective in the control of such
insects as the budmoth, cherry shoot borer, apple curculio, and saskatoon
sawfly. Saskatoons are also attacked by various fungi and a few bacteria, but
so far no viruses or mycoplasmas are known (Davidson 1987). Important diseases
include saskatoon-juniper rust (Symnosporangium sp.), leaf and berry
spots (Entomosporium sp.), dieback and cankers (Cytospora sp.,
Nectria sp.), blackleaf and witches broom (Apiosporina sp.),
brown rot (Monilinia amelanchieris), and fireblight [Erwinia
amylovora (Burrill) Winslow et al.] (St. Pierre 1991). Control procedures
include pruning to remove infected parts, site selection (especially for
saskatoon-juniper rusts) and agronomic practices (irrigation and cultivation).
Saskatoon fruit grows in clusters. The fruit ripens almost evenly and the
whole crop can usually be picked at one time. Yields of up to 10 tonnes/ha can
be obtained with proper management.
The fruit can be picked by hand, or mechanically, using a hand-operated
vibrator or a self-propelled blueberry harvester. For the fresh fruit market,
the fruit should not be overripe or crushed, torn, or bruised.
The nutritional value of saskatoon berries on a dry weight basis is listed in
Table 2. Saskatoon berries contain higher levels of protein, fat, and fiber
than most other fruit. Tuba et al. (1944) indicated that fresh saskatoon
berries might be a useful source of vitamin C. Panther and Wolfe (1972),
however, reported a negligible ascorbic acid content and that an ascorbic acid
oxidizing enzyme system was present in the berries.
Total solids content ranges from 20 to 29.4% fresh weight with 15.9 to 23.4%
sucrose and 8 to 12% reducing sugars (Mazza 1979, 1982). Wolfe and Wood (1971)
found that the sugar content increases slowly as the fruit matures and then
accelerates markedly before ripening. Their results also indicated that
fructose content decreased rather markedly (25%) after the fruit ripened while
the glucose content remained unchanged. Berry pH values range from 4.2 to 4.4
and titratable acidity values (% malic acid) from 0.36 to 0.49% (Mazza 1979;
Green and Mazza 1986). The predominant acid in saskatoon berries is malic
(Wolfe and Wood 1972) and the predominant aroma component is benzaldehyde
(Mazza and Hodgins 1985). There are at least four anthocyanins in ripe
saskatoon berries; cyanidin 3-galactoside accounts for about 61% and
3-glucoside for 21% of total anthocyanins (Mazza 1986).
The saskatoon berry is a very new commercial fruit, yet several food processors
are already using wild and cultivated berries in their food products (Fig. 2).
There seems to be considerable potential for expansion of production and
processing of saskatoon berry as many processors and distributors have reported
they would use large quantities of this unique fruit if they had an assured
supply at a reasonable price. For successful mass production of saskatoons,
however, consistently higher yields and quality and improved pest control are
required. This can only be achieved through increased research efforts.
- Davidson, C.G. and G. Mazza. 1991. Variability of fruit quality and plant
height in populations of saskatoon berries (Amelanchier alnifolia
Nutt.). Fruit Var. J. 45:162-165.
- Davidson, J.G.N. 1987. The principal diseases of commercial saskatoons. Agr.
Forestry Bul., Univ. of Alberta. Spring, 1987, 6-7.
- Green, R.C. and G. Mazza. 1986. Relationships between anthocyanins, total
phenolics, carbohydrates, acidity and colour of saskatoon berries. Can. Inst.
Food Sci. Technol. J. 19:107-113.
- Harris, R.E. 1972. The saskatoon. Agr. Can. Publication 1246.
- Harris, R.E. 1980. Propagation of Amelanchier, Amelanchier alnifolia
cv. Smoky in vitro. West. Can. Soc. Hort. Sci. 19:32-34.
- Mazza, G. 1979. Development and consumer evaluation of a native fruit
product. Can. Inst. Food Sci. Technol. J. 12(4):166-169.
- Mazza, G. 1982. Chemical composition of Saskatoon berries (Amelanchier
alnifolia Nutt.). J. Food Sci. 47:1730-1731.
- Mazza, G. 1986. Anthocyanins and other phenolic compounds of saskatoon
berries (Amelanchier alnifolia Nutt.). J. Food Sci. 51:1260-1264.
- Mazza, G. and M.W. Hodgins. 1985. Benzaldehyde, a major aroma component of
saskatoon berries. HortScience. 20:742-744.
- Nelson, S.H. 1987. Effects of stock plant etiolation on the rooting of
saskatoon berries (Amelanchier alnifolia Nutt.) cutting. Can. J. Plant
- Panther, M. and F.H. Wolfe. 1972. Studies on the degradation of ascorbic acid
by saskatoon berry juice. Can. Inst. Food Sci. Technol. J. 5(2):93-96.
- Pruski, K., J. Nowak, and G. Grainger. 1990. Micropropagation of four
cultivars of saskatoon berry (Amelanchier alnifolia Nutt.). Plant Cell
Tissue Organ Culture 21:103-109.
- St. Pierre, R.G. 1989. Magnitude, timing and causes of immature fruit loss in
Amelanchier alnifolia (Rosaceae). Can. J. Bot. 67:726-731.
- St. Pierre, R.G. 1991. Growing saskatoons: A manual for orchardists. Univ.
of Saskatchewan, Saskatoon, Saskatchewan.
- Tuba, J., G. Hunter, and L.L. Kennedy. 1944. On sources of vitamin C. II.
Alberta native fruits. Can. J. Res. 22(2):33-37.
- Wolfe, F.H. and F.W. Wood. 1972. Non-volatile organic acid and sugar
composition of saskatoon berries during ripening. Can. Inst. Food Sci.
Technol. J. 4:29-30.
Table 1. Physico-chemical characteristics of five saskatoon
|Cultivar ||10 Berry weight (g) ||pH ||Titratable acidity (% malic acid) ||Total solids (% dry wt) ||Soluble solids (% sucrose) ||SS/Ac ||Anthocyanin content (mg/100 g berries)|
|Honeywood ||12.7 ||3.8 ||0.54 ||25.6 ||18.7 ||34.7 ||114|
|Northline ||8.0 ||3.9 ||0.45 ||25.1 ||16.1 ||35.5 ||111|
|Porter ||7.8 ||3.8 ||0.56 ||22.7 ||16.3 ||29.5 ||108|
|Regent ||6.8 ||4.4 ||0.29 ||20.8 ||14.8 ||52.8 ||72|
|Smoky ||10.1 ||4.5 ||0.25 ||27.0 ||16.3 ||66.2 ||68|
Table 2. Nutritional composition of 'Smoky' saskatoon berries.
(% dry wt±SD)
||Fig. 1. 'Smoky' saskatoon berries at maturity.
Fig. 2. Commercial products of saskatoon berry.
Last update September 15, 1997