Potential for Shake and Catch Harvesting of Hazelnuts

View the project final report

Commodities

• Nuts: hazelnuts

Practices

• Crop Production: agroforestry, silvopasture
• Education and Training: on-farm/ranch research
• Farm Business Management: feasibility study
• Production Systems: agroecosystems, integrated crop and livestock systems

Nearly all hazelnuts produced in the United States are grown in Oregon’s Willamette Valley.
Hazelnuts are typically harvested by sweeping them off the orchard floor every fall. This “sweep
harvest” method necessitates keeping orchard floors very flat, and free of vegetation/debris that
may interfere with harvest.
Keeping orchard floors “clean” is achieved through frequent flail mowing, leveling and herbicide
applications. These practices can lead to soil degradation. Additionally, because sweep
harvesting cannot begin until all nuts have fallen from the tree, harvest is often conducted after
the onset of the fall rains which can lead to additional compaction and difficulties separating the
nuts from debris and mud.
We are proposing to study the potential for shake and catch harvesting in hazelnut production. If
feasible, shake and catch harvesting could allow for a whole host of environmental benefits as
well as increase the economic viability of small to midsize hazelnuts orchards.
With shake and catch harvesting techniques, nuts are harvested straight from the tree by shaking
the trunk, causing nuts to fall onto an inverted umbrella and into a tote. This would allow for
much less intensive orchard floor management, as nuts do not have to be swept off a clean and
manicured orchard floor. Deep-rooted cover crops could be grown to maximize their soil
building potential, and animals could be integrated after the harvest to help control disease and
maintain fertility. Finally, harvest could happen earlier in the fall, decreasing the potential for
harvesting in the rain.
In order to test the viability of shake and catch harvesting, we are proposing to compare yield,
and timing of “shake and catch harvesting” vs “sweep harvesting” in order to assess whether
shake and catch harvesting has the potential to replace traditional sweep methods in hazelnut
production in Oregon and beyond.
We plan to share our experience and findings with the wider agricultural community through
online demonstration videos, a dedicated page on our website and regular updates via our
Facebook page, Instagram account and email list. We plan to host two field days on our farm and
to share our findings at the Oregon Small Farms Conference.

1) Compare yield of shake and catch to conventional harvest
a. We want to know if we can harvest as many nuts with a “shake and catch
harvester” as with a “conventional sweep harvester”. We will be measuring
yield by finding the percentage of total nuts we are able to harvest from a
given block of 118 trees (one acre). We will then compare our harvest
percentage to the industry average.
2) Compare quality of nut in shake and catch to conventional harvest
a. Conventional sweep harvesting waits for hazelnuts to fall to the ground at
maturity. Shake and catch harvesting will be conducted earlier in the fall
before nuts drop to the ground. Therefore, we want to know whether shake
and catch harvesting has any effect on the ability of the hazelnut to fully fill
its shell. We will be measuring quality much in the same way that major
hazelnut processors do: by looking at percentage of nut fill. We will crack
and separate nuts from shells for our given block of 118 trees. Then we will
divide weight of shell by weight of nut to get our nut fill percentage and
compare that to the industry average.
3) Compare percent blanks in shake and catch to conventional harvest
a. We want to know if shake and catch harvesting has any effect on the
percentage of nuts harvested that are blanks (have no nut inside). We’ll test
this much the same way that large processors do, by cracking random samples
of nuts from our test block one at a time and recording the percentage that are
blank. We will then compare this to the industry average as well as to other
blocks in our orchard.
4) Compare harvest timing of shake and catch to conventional harvest
a. Shake and catch harvesting has the potential to occur and be completed earlier
than sweep harvesting methods. We plan to document actual and preferred
harvest dates in 2018 and 2019 and then compare those with the industry
average harvest dates for those years.