3
Biology
Primary bud break
Plants break bud in early spring. Initial, or primary,
bud break, which occurs from late April to early
May, produces the inflorescence and two or three
basal leaflets. The time period for the bud stages
described in Table 1 is approximately two to three
weeks in an average year, but cold or warm spring
temperatures can cause this period to vary.
Saskatoon berries are prone to uneven ripening,
which may be due to uneven bloom time. It is
therefore possible to have some buds in different
stages on the same bush, with the buds on the south
side more advanced than those on the north side
and growth on outside branches more advanced
than inside ones.
Also, budding in different varieties and in orchards
in different locations may not occur at the same
time (see chapter on Orchard Establishment). When
estimating the bud stage for the crop, it is important
to judge what stage most of the buds are in.
Saskatoon berry plants are 1 to 5 m tall
(3 - 16
ft.) shrubs with alternately arranged buds
and leaves. Flowers and fruit form in clusters on
the branches. Plants may be 3 to 6 m (10 - 20 ft.)
wide if left unpruned.
The reddish purple to black, fleshy, berry-like fruit
contains several seeds. Branches are smooth with
chocolate brown colouring, and twigs are reddish
brown.
Vegetative and
reproductive buds
An understanding of the bud stages is important for
the proper timing of sprays for pest management
(
see Appendix 1.11). Knowing the bud stages
of the crop is also significant for predicting and
understanding frost damage as well as the timing of
harvest operations.
During the first two development years of plants
growing from suckers or root cuttings (clonal plants),
all the alternately arranged buds produced on new
shoots are juvenile tissue or leaf or vegetative
buds. During the first three to four years of seedling
plant development, all the buds produced on new
shoots are juvenile tissue. Once the clonal or
seedling plants have passed the juvenile stage of
development, all the buds are mixed fruit-leaf buds,
and the plants will begin to produce fruit in addition
to leaves.