GRAPE HARVESTERS PICKING HEADS
How's and Why's of Picking Heads
Trunk shaker heads feature the best quality picking of cordon trained grapes. Imagine picking first quality grape berries, leaving most of the rot, raisins, and second crop behind! You still can pick everything if you want to, but as grape quantities increase, quality will become more important!
A TRUNK SHAKER WORKS
The principle is acceleration and instant deceleration of mass. Have you
ever gone fly fishing, snapped your leader too hard and returned with
a leader tip with no fly? In other words:
The grape trunk shaker head moves the vine with berries to the right perpendicular
to the vine row, and while the berries are moving right, the head reverses
direction, moving the trellis to the left. This is accomplished be a pair
of horizontal picking rails moving along the trellis. The picking rails
address the trunk and grape stakes below the cordon height level, so as
not to damage cordon and spurs or canes. The action the berries receive
is similar to cracking the whip.
You can adjust the frequency of the shake by raising or lowering the picking head RPM. You can adjust the stroke by changing the rotational weights enclosed in the picking head. All adjustments are easily made.
Machine harvesting of grape berries results in individual loose berries.
The trunk shaker harvests grape loads that are higher in sugar compared
to the identical hand harvest, contains the best of the berries and has
a lower MOG (Material Other Than Grapes; leaves rot etc.). Machine harvesting
with a trunk type shark er head doesn't fracture the canes nor defoliate
the leafing zones like a pivotal striker or bow rod shaking head. Trunk
shaker picking heads do exactly as their name implies.
Pivotal striker and bow rod picking heads are canopy or foliage shark
ers. Whenever you pass a shaking devise through the foliage or canopy,
you will remove and fragment some leaf particles. Canes are also broken
more often. You see vineyard defoliation within 10-15 days following harvesting.
Much of the defoliation occurs from broken leaves and the leaf being coated
with crushed grape juice. Canopy Shakers were designed for cane pruned
or young vineyards.
Please note: Developing new vineyards are flexible and really emulate
cane pruned vineyards. Trunk shakers do not work well in these young
vineyards and or cane pruned vineyards. On the other hand as the vineyards
matures and becomes more rigid,the energy of the trunk shaker readily
transmits to the vine. The mature vineyard becoming more rigid will break
and defoliate easier using the pivotal striker or bow rod head.
By using the trunk shaker head the grapevines aren't defoliated, they
have time to recover from the growing season and harvest; storing carbohydrates
prior to going dormant. The grapevines which have stored carbohydrates
have more energy the following spring at bud break.
Using bow rod and pivotal striker heads verses the trunk shaker on spur pruned vineyards, will show a decrease vineyard vigor and yields over time.
We also offer the AIM "Soft Touch"; a hydraulically controlled
system that automatically adjusts the picking rail spacing and applied
forces to the vine/stake diameter allowing large and small vines in the
same row the same applied force.