TIME TO CONSIDER
36
Almond Facts
JANUARY | FEBRUARY 2017
more information and check with your pest control advisor
for product availability and recommended rates.
Foliar Nutrients at Bloom
Boron and zinc foliar nutrients applied either in the
post-harvest period (e.g. September) or at pink bud have
been shown to increase yield in almond trees in many
orchard situations. Interestingly, applying these products
after pink bud have either failed to increase yield or
decreased kernel yields. Concentration of boron should
not exceed 400 ppm of boron in solution, and good results
have been shown with rates between 200 to 400 ppm,
depending on the tree’s boron status. Zinc applications
appear to have a synergistic effect with boron, meaning
that the combination of the treatments has been shown to
outperform either material sprayed alone. Interestingly,
zinc applied alone was not found to increase yields.
Other trials have found limited to no benefits from the
application of other micronutrients at bloom unless
nutrient deficiencies are present.
Be Careful with Bees
There has been a lot of concern about honeybee health
related to fungicide and insecticide applications within
orchards. More is being learned every year about the
impacts of pest management practices on hive health.
Recently, The Almond Board of California released an
excellent resource titled “Honey Bee Best Management
Practices for California Almonds (
.
com/pollination).” This resource provides an overview of
the research conducted and the recommendations generated
from the results and conclusions.
The University of California Agricultural and Natural
Resources Integrated Pest Management Program
has developed a nice website that provides toxicity
information of various pesticides (ipm.ucanr.edu/
beeprecaution/). Precaution rankings (I, II, III) have been
created based on all of the currently available scientific
studies. The table does include effects on bee brood if
research is not available. Lack of toxicity data for honey
bee brood means that there is no data currently available,
not that the material has no impact. Always proceed with
caution and err on the side of bee safety.
Proper Tree Planting
When planting a new orchard, it is important to take the
proper precautions to avoid tree loss. Trees should be
planted as soon as possible after delivery. Prior to delivery,
make sure the field is prepared, which includes ensuring
that soil fumigants have completely dissipated, soil clods
are broken down and workable, and large amounts of
organic material (e.g. grass clippings, compost) are not
present in the planting areas. Berms are recommended
for most soils to prevent crown infections by Phytophthora.
Berms may not be needed in soils with high infiltration
rates. If planned, berms should be pulled prior to tree
planting. Do not pull berms as an after-thought:
soil covering the graft union will increase the risk
of Phytophthora.
To prevent root drying, keep the roots moist and cover
with a tarp when being transported within the field. Do
not prune tree roots unless they are broken. Holes should
be dug at the time of planting if possible, but if not, as
close to the timing of planting to prevent “glazing” of the
soil by the sun. If the holes are dug with an auger or prior
to the planting day, slice the sides of the hole with a shovel
to break any crust that may have formed. When planting,
dig a large enough hole to fit the entire root system
without bending or wrapping. Forcing trees into planting
holes causes “J-rooting” and increases the chance of crown
Heavy rains can flood fields, preventing access. Driving
within these fields can create compaction issues that
will take several years to correct. Plan ahead!
Almond flowers are sensitive
to a wide variety of diseases.
Fungicides should be
considered when inclement
weather is in the forecast.
