RFID Tagging of Seedlings
JETOMA Design Team
Matt Ringstad
Thomas Mohr
Jeremy Tryall
Problem Owners
• Mr. Doug St. John
– Executive Director of the Precision Forestry
Cooperative
• Dr. Jim Fridley
– Professor in the Mechanical Engineering and
Forest Engineering Departments at the
University of Washington
Stakeholders
• Dr. David Briggs
– Director of the Stand Management Cooperative
• Mr. Jeff Mehlschau
– Resident Engineer at the Weyerhaeuser Regeneration
Facility at Rochester, WA
• Prof. Denise Wilson
– Assistant Professor in the Electrical Engineering
Department at the University of Washington
• Mr. Sean Hoyt
– Electrical Engineer in charge of developing the tag
reader
Expectations
Problem Owners
• Determine a method and process to attach
RFID tags to seedlings
• Consider factors such as manufacturing
implementation, location on seedlings,
mortality of seedlings, and newly developed
technology to read RFID tags
Professor Briggs
• Concerned about stand reforestation issues
• Represents stand managers’ and
landowners’ expectations
• Expects that tag attachment does not
succumb to vandalism
Jeff Mehlschau
• Introducing a mortality rate that exceeds
current mortality rates of planted seedlings
is unacceptable
• Tags should not hinder growth of seedlings
in the field
• Delaying production up to a week is
unacceptable
• Injection not viable
Prof. Denise Wilson & Sean Hoyt
• Attach a tag to a tree in such a way that it
will not interfere with the reader’s abilities
Problem Background
• RFID Tagging of trees is a new field of
interest
• Want to be able to give a tree a serial
number to develop a stand database
– can record different management activities,
such as pruning, PCT, date planted, etc.
Different Tags Available
• Nail Tags
• Glass capsule tags (for
animal identification)
• Heavy duty tags
Nursery Background
• Two types of nurseries to focus on:
– container
– bareroot
• Busy season starts right after Christmas and
runs until late February
• Whatever else happens, our process has to
keep up with production!
• Seedling types
– 1-0 & 2-0
– 1D0
• leads to 1+1 (inexpensive, grows well)
• one year at high density, one year at low density
• 73% of seedlings
– 2D0
• leads to 2+1, 2+2
• two years at high density, then one or two years at
low density
– Plug 1
Production rates
• Container Nursery
–
–
–
–
–
7 1/2 hour days
30,000 to 50,000 trees per day with 48 cavities
75,000 to 80,000 trees per day with 60 cavities
up to 125,000 trees per day with 77 cavities
hope to get production up to 80,000 to 100,000
trees per day with the 48 cavity boxes by
automating the sorting system process
• Mima Facility
– largest Douglas fir nursery in the world
• produces up to 50 million seedlings a year
– seedlings are grown in beds out in the open
• Once at sorting lines:
– 7 conveyer lines
– process between 9,000 and 17,000 seedlings
per hour per line
– two 7 1/2 hour shifts per day
• After sorted
– bundled, roots pruned, bagged, and put into the
freezer at 28° F
• Minimum Dimensions
– 1+1 seedlings
• 4mm caliper
• 10” stem
– 2+1 seedlings
• 7-8mm caliper
• 21-28” stem
Functional Requirements
• Choose a location for the RFID tag on the
seedling
• Develop a method for RFID tag attachment
• Choose a time within the sorting process at
which to apply the method
• Tags must be durable
Constraints
• Above all, tagging process must keep up
with the nursery processing rates
• Seedling mortality rate is not to exceed 5 to
10 percent once planted in the field
• The tag should somehow be inside the tree
or under the ground
• Tags must not slow the seedling’s growth to
less than three feet in four years
• The distance between the tag and the reader
can be at maximum about 10 inches
• Tagging orientation has to be perpendicular
to the reader for maximum reading range
• The tag needs to be of a certain type and
dimension to be determined later, but
should ideally be no larger than 4 mm wide
We Propose the Following:
• A process of attachment to bareroot seedlings that
can be implemented at a typical nursery
– Focus on 1+1, bareroot seedlings
– Attachment done after the seedlings are sorted
and before they are put in the freezer
– Attachment done on the rootball
– Use a tag with a staple/pin/nail/brad as a
method of attachment
Recommendation
• We strongly recommend that a survivability study
be done
– We don’t know exactly how the seedlings will react to
the tagging process
– The idea is that we do not want to start tagging at a
nursery and induce unacceptable mortality rates or
severely hamper seedling growth
– Acquire a test batch of bareroot seedlings
– Tag and then plant them at a test plot at Pack Forest
– Can construct a database and monitor seedlings for
growth over the critical first four years