Patent Publication Number: US-2019193284-A1

Title: Systems, methods and apparatuses for processing seedlings

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of 35 USC 119 based on the priority of copending U.S. Provisional Application No. 62/609,794 filed Dec. 22, 2017, which is herein incorporated by reference. 
    
    
     FIELD 
     This application claims the benefit of 35 USC 119 based on the priority of copending U.S. Provisional Application No. 62/609,794 filed Dec. 22, 2017, which is herein incorporated by reference. The present subject matter of the teachings described herein relates generally to systems, methods and apparatuses for handling and/or processing seedlings. 
     BACKGROUND 
     European Patent Publication No. 2,193,193 (Stout) discloses an apparatus for preparing plant tissue (e.g., somatic embryos, embryogenic tissue, organogenic tissue, vegetative tissue, seeds, etc.) for plant production includes a first station having a first rack system configured to support at least one culture vessel, a second station having an automated member configured to manipulate the at least one culture vessel and a third station having a second rack system configured to support the at least one culture vessel after being manipulated by the automated member. The second station can be selectively adjusted to perform more than one operation required in the plant development. According to exemplary embodiments, the apparatus may include more than one second station (e.g., operational stations, etc.). 
     U.S. Pat. No. 9,572,300 (Jamruszka-Lewis) discloses methods of transferring a plurality of plant somatic embryos to germination medium. The method includes the steps of: (a) depositing a plurality of plant somatic embryos on a surface of a substrate, wherein the substrate has a top surface and a bottom surface; (b) inverting the substrate with the disposed plurality of plant somatic embryos over germination medium contained in a container such that the plurality of plant somatic embryos disposed on the top surface of the substrate are opposite to and facing a surface of the germination medium; and (c) applying a sufficient force to the bottom surface of the substrate such that the plurality of plant somatic embryos are dislodged from the substrate and fall onto the surface of the germination medium. Steps (b) and (c) of the methods can be performed manually or as part of an automated system. The methods also include subjecting the plurality of plant somatic embryos on germination medium to suitable environmental conditions for a period of time sufficient to promote germination of the plurality of plant somatic embryos. 
     U.S. Pat. No. 5,247,761 (Bigelow) discloses a computer controlled seedling transfer apparatus having a pair of free-wheeling conveyors for supporting a commercial grower&#39;s seed flat and pot flat. Each conveyor includes an associated indexing mechanism for gripping the respective flat and translating the flat along the conveyor so that certain of the flat recesses are aligned with a transfer station between the flats. A seedling transfer mechanism is supported above the conveyors so that the mechanism can be moved transversely between the seed flat and pot flat. The seedling transfer mechanism includes extendable gripping fingers for gripping a seedling, removing it from the seed flat, transferring it to a specific pot flat recess and replanting the seedling. The indexing mechanisms for the two flats are computer controlled, as is the seedling transfer mechanism, to optimize the seedling transfer operation and to ensure that the pot flat is completely filled with seedlings. In one embodiment, a sensor, such as a camera or an infrared sensor, are mounted over the seed flat and pot flat to sense the condition of the recesses in the flats. The computer responds to the sensed conditions of the recesses to control the sequence of transfer moves, for example to avoid attempted transfers from empty seed flat recesses. A nozzle is provided in another embodiment that is associated with the seedling transfer mechanism that is used to facilitate removal, transfer and replanting of the seedling. The seedling transfer mechanism includes a pair of resilient gripping fingers with a flexible web extending therebetween. The web slightly bends the seedling during the transfer so that the seedling does not get tangled with the transfer mechanism. 
     U.S. Pat. No. 7,117,634 (Pelton) discloses a method of making tree seedling plugs which permits the plug to be transplanted earlier. The tree seeds are planted in a structured soil growing medium, and a miniplug is formed which may is then transferred to a standard size growing cell for further development to form the plug. 
     U.S. Pat. No. 5,842,306 (Onosaka) discloses a transplanter for transplanting a plug seedling grown in each cell of a plug seedling tray to a certain size to a transplanted seedling tray or a pot comprising a plug seedling carrying means for carrying the plug seedling tray, a transplanted seedling carrying means spaced at a certain distance from the plug seedling carrying means for carrying the transplanted seedling tray or the pot, a seedling transfer mechanism disposed across the plug seedling carrying means and the transplanted seedling carrying means for transferring the plug seedling from the position above the plug seedling tray to the position above the transplanted seedling tray, the seedling transfer mechanism including an endless chain or belt passing above the plug seedling carrying means and the transplanted seedling carrying means and circulating in a plane made at a certain angle with respect to a horizontal plane, the endless chain or belt being provided at its outer peripheral surface with receptacles for containing plug seedlings to be spaced at a predetermined distance with respect to each other, a seedling picking-out mechanism for picking out the plug seedling from the cell of the plug seedling tray and introducing it into one of the receptacles of the seedling transfer mechanism, and a seedling planting mechanism for picking out the plug seedling from the receptacle and planting it in the cell of the transplanted seedling tray or the pot. 
     US Patent Publication No. 2012/0003074 (Rubatino) discloses a pick-up and delivery system including a pick-up assembly and a delivery assembly. The pick-up assembly includes a robotic arm, a pick-up device rotatably mounted on the robotic arm, and a first vacuum pressure supply port operably connected to the pick-up device. The delivery assembly includes an insertion device and a second vacuum pressure supply port. The insertion device may include an insertion member and a release assistance rod arranged inside the insertion member. The release assistance rod is moveable between an extended position and a retracted position. When the release assistance rod is in the extended position, a proximal end extends beyond an end of the insertion member. Further aspects are directed towards methods for grasping and releasing an object with a pick-up and delivery system. 
     The process of removing seedlings from germination media, selecting suitable seedlings, picking up the suitable seedlings and inserting the seedlings into growth media such as soil plugs is typically laborious and inefficient. 
     A skilled technician may be involved in evaluating morphological features of each seedling and manually selecting desirable seedlings. The skilled technician may then transfer the selected seedlings to growth medium. This can provide a major production bottleneck when thousands of seedlings are being processed. 
     Although systems have been developed that are effective in transporting seedlings, problems are encountered. For example, in some applications, seedlings are hydrated to prevent damage from desiccation causing them to often stick to delivery systems and incur damage during removal attempts. Sticking can cause orientation or placement issues and difficulty in inserting seedlings in growth media with the possibility of wasting viable seedlings. 
     Thus, there is a need in the industry to develop new systems, apparatuses and methods for plant seedling identification, pick-up and/or delivery. 
     SUMMARY 
     An aspect of the disclosure provides a method of inserting seedlings into soil plugs, the method comprising: 
     automatically identifying a target seedling located in a pick-up area using seedling detection apparatus; 
     picking-up the target seedling with an automated seedling handling apparatus; 
     transporting the target seedling to an insertion area; 
     providing a first soil plug in the insertion area to receive the target seedling, the first soil plug having a first plug end, a second plug end longitudinally spaced apart from the first plug end and a longitudinal slit extending from the first plug end toward the second plug end; 
     spreading the slit in the first soil plug; 
     inserting a root portion of the seedling into the slit while a stem portion of the seedling is positioned outside the first soil plug; 
     stripping the target seedling from the handling apparatus whereby the seedling remains received within the slit in the first soil plug. 
     In an embodiment, the soil plug is a stabilized soil plug, optionally stabilized with a stabilization compound and/or polymeric compound. 
     In an embodiment, the seedling handling apparatus comprises a body having a vacuum channel configured to receive the root portion of a seedling and is operable to pick-up the target seedling by sucking the root portion of the target seedling into the vacuum channel. 
     In another embodiment further comprising longitudinally aligning the vacuum channel with the slit, whereby the root portion of the target seedling is oriented substantially parallel to the slit. 
     In another embodiment, step f) comprises inserting a tip of the seedling handling apparatus containing the target seedling into the first plug to insert the root portion of the seedling within the slit. 
     In yet another embodiment, the slit in the first soil plug is spread by the seedling handling apparatus. 
     In an embodiment, the seedling handling apparatus comprises a ploughshare portion proximate the tip and positioned so that the ploughshare precedes the tip as the seedling handling apparatus is translated relative to the first soil plug to spread/open the slit in advance of the tip. 
     In another embodiment, step f) is performed while imparting relative, longitudinal movement between the handling apparatus and the first soil plug. 
     In another embodiment, step f) is performed while translating the tip of the handling apparatus longitudinally through the slit in the first soil plug. 
     In yet another embodiment, the target seedling is mechanically stripped from the handling apparatus in step g). 
     In an embodiment, the target seedling translates with the handling apparatus until engagement between the stem portion of the target seedling and the first soil plug inhibits translation of the target seedling relative to the first soil plug, after which continued translation of the handling apparatus strips the target seedling from the handling apparatus. 
     In another embodiment further comprising closing the slit around the root portion of the target seedling to enclose the root portion within the first soil plug. 
     In another embodiment, identifying the target seedling comprises inspecting a plurality of seedlings in the pick-up area using a camera vision system, identifying at least one of the plurality of seedlings that satisfies a pre-determined seedling selection criteria using a controller, and designating at least one seedling as the target seedling to be picked-up. 
     In yet another embodiment, the pre-determined seedling selection criteria comprises at least one of seedling area, elongation and spread. 
     In an embodiment, the pick-up area comprises a pick-up table for holding a plurality of seedlings and the target seedling is picked-up from amongst the plurality of seedlings. 
     In another embodiment, the pick-up table rotates about a table rotation axis, and wherein the target seedling is picked-up while the pick-up table is rotating. 
     In another embodiment, the pick-up table rotates to transport the plurality of seedlings from a deposit region where the plurality of seedlings are deposited on the pick-up table to an ejection region and further comprising ejecting unselected seedlings from the pick-up area when they enter the ejection region. 
     In another embodiment, the unselected seedlings are ejected from the pick-up table via a stream of air. 
     In another embodiment the method further comprises receiving a plurality of seedlings from a growing station and washing the plurality of seedlings to remove excess growing material at a washing station before the plurality of seedlings are positioned in the pick-up area. 
     In yet another embodiment, the method further comprises transferring the first soil plug containing the first seedling to a packing station and automatically packing the first soil plug containing the first seedling into a holding tray using an automated packing apparatus. 
     Another aspect of the disclosure includes an apparatus for handling seedlings, the apparatus comprising: 
     a body having an attachment portion that is connectable to a driving member (e.g. robot); 
     a vacuum channel comprising a first end fluidly connectable to a vacuum generator, an open tip spaced apart from the first end and a hollow channel interior extending therebetween, the tip terminating in a rim that is sized to slidingly receive a root portion of a seedling and engage a stem portion of the seedling, whereby when a vacuum is applied to the vacuum channel the root portion of the seedling is sucked into the channel interior and the stem portion of the seedling remains outside the vacuum channel. 
     In an embodiment, the vacuum channel further comprises a throat portion disposed between the first end and the tip, and wherein the throat portion has a smaller area than the tip and the vacuum channel generally narrows from the tip to the throat portion. 
     In another embodiment, the body has a base surface that is substantially downward facing when the apparatus is in use, and wherein the tip extends beyond the base surface. 
     In yet another embodiment, the base surface has a base width in a lateral direction and the tip has a tip width in the lateral direction that is less than 25% of the base width. 
     In another embodiment, the rim has a first portion lying in a first plane, and a second portion lying in a second plane that intersects the first plane at an oblique angle. 
     In another embodiment, the second plane is substantially parallel to the base surface. 
     In an embodiment, the vacuum channel extends along a channel axis and wherein the first plane is orthogonal to the channel axis. 
     In another embodiment, a line of intersection between the first plane and the second plane is spaced apart from the channel axis. 
     In yet another embodiment, the channel axis is inclined at an oblique angle relative to a plane containing the base surface. 
     In an embodiment, the body is rotatably connected to the driving member and can rotate about a rotation axis. 
     In another embodiment, the tip is configured to be inserted into a soil plug to deposit the root portion of the seedling within the soil plug. 
     In another embodiment, the tip is positioned such that when the tip is inserted into the soil plug the base surface bears against an upward facing side surface of the soil plug. 
     In another embodiment the apparatus further comprises a ploughshare portion positioned below the base surface and aligned with the tip, the ploughshare portion configured to be inserted into the soil plug and form an opening/slit in the soil plug into which the root portion of the seedling is deposited. 
     In an embodiment, the apparatus is translatable relative to the soil plug in an insertion direction to translate the ploughshare and tip through an interior of the soil plug, whereby the tip trails the ploughshare portion through the interior of the soil plug. 
     In another embodiment, the ploughshare has a base adjacent the tip of the vacuum channel and a leading edge spaced from the base in insertion direction, and wherein the leading edge is narrower than the base. 
     In another embodiment, the ploughshare tapers from the base to the leading edge. 
     In yet another embodiment, the ploughshare portion extends between the base surface and an outer surface of the tip. 
     In an embodiment, the body and vacuum channel are of integral, one-piece construction. 
     In another embodiment, the vacuum channel extends along a channel axis and when the vacuum apparatus is in use the channel axis is inclined at an oblique channel angle relative to a vertical axis. 
     In another embodiment, the channel angle is between about 15 degrees and about 60 degrees, and preferably is about 45 degrees. 
     A further aspect of the disclosure includes a system for inserting seedlings into soil plugs, the system comprising: 
     a primary transport apparatus; 
     a soil plug station configured to receive a plurality of soil plugs and having a plug handling apparatus to transfer a first soil plug from the soil plug station to the transport apparatus; and 
     a seedling handling station downstream from the soil plug station and configured to receive a plurality of seedlings, the seedling station having a seedling handling apparatus; 
     wherein the transport apparatus is operable transport the first soil plug from the soil plug station to the seedling station and when the first soil plug is at the seedling station the seedling handling apparatus is configured to insert a first seedling into the first soil plug. 
     In an embodiment, the seedling handling station comprises a pick-up area to receive the plurality of seedlings and an inspection apparatus configured to inspect the plurality of seedlings in the pick-up area and automatically identify at least one seedling that is acceptable to be selected as the first seedling. 
     In another embodiment, the inspection apparatus comprises at least a first camera to visually inspect the plurality of seedlings and a controller communicably linked to the camera process the visual data received from the camera and identify acceptable seedlings. 
     In yet another embodiment, the controller is configured to identify acceptable seedlings by comparing at least one physical attribute of each seedling to a pre-determined seedling criteria threshold. 
     In another embodiment, the pick-up area comprises a rotatable pick-up table that supports the plurality of seedlings such that the plurality of seedlings rotate with the pick-up table. 
     In yet another embodiment, the seedling handling apparatus comprises a robot having an end effector configured to pick-up seedlings from the pick-up table. 
     In an embodiment, the seedling handling apparatus is operable to pick-up seedlings from the pick-up table while the pick-up table is rotating. 
     In another embodiment, the end effector comprises:
         a) a body having an attachment portion that is connectable to a driving member;   b) a vacuum channel comprising a first end fluidly connectable to a vacuum generator, an open tip spaced apart from the first end and a hollow channel interior extending therebetween, the tip terminating in a rim that is sized to slidingly receive a root portion of a seedling and engage a stem portion of the seedling, whereby when a vacuum is applied to the vacuum channel the root portion of the seedling is sucked into the channel interior and the stem portion of the seedling remains outside the vacuum channel.       

     In another embodiment, the system further comprises a washing station configured to receive the plurality of seedlings and to wash the plurality of seedlings to separate the plurality of seedlings from excess growing material, and a secondary transport apparatus to transfer the washed plurality of seedlings from the washing station to the seedling handling station. 
     In yet another embodiment, the system further comprises a packing station downstream from the seedling handling station to receive the first soil plug containing the first seedling and automatically packing the first soil plug containing the first seedling into a holding tray using an automated packing apparatus. 
     In various embodiments, the methods use a system described herein. In various embodiments, the system comprises an apparatus for handling seedlings described herein. 
     This summary is intended to introduce the reader to the more detailed description that follows and not to limit or define any claimed or as yet unclaimed invention. One or more inventions may reside in any combination or sub-combination of the elements or process steps disclosed in any part of this document including its claims and figures. 
    
    
     
       DRAWINGS 
       The drawings included herewith are for illustrating various examples of articles, methods, and apparatuses of the teaching of the present specification and are not intended to limit the scope of what is taught in any way. 
       In the drawings: 
         FIG. 1  is a perspective view of one example of a system for processing seedlings; 
         FIG. 2  is another perspective view of the system of  FIG. 1 ; 
         FIG. 3  is a perspective view of a portion of the system of  FIG. 1 ; 
         FIG. 4  is the perspective view of  FIG. 3  with the portions of the system in a different configuration; 
         FIG. 5  is the perspective view of  FIG. 3  with the portions of the system in a different configuration; 
         FIG. 6  is a perspective view of a portion of one example of a seedling handling apparatus; 
         FIG. 7  is a front view of the portion of the seedling handling apparatus of  FIG. 6 ; 
         FIG. 8  is a top view of the portion of the seedling handling apparatus of  FIG. 6 ; 
         FIG. 9  is a bottom view of the portion of the seedling handling apparatus of  FIG. 6 ; 
         FIG. 10  is a cross-sectional view taken along line  10 - 10 ; 
         FIG. 11  is a rear view of the portion of the seedling handling apparatus of  FIG. 6 ; 
         FIG. 12  is a schematic illustration of the portion of the seedling handling apparatus of  FIG. 6  in a first position relative to a soil plug; 
         FIG. 13  is a cross-sectional view taken along line  13 - 13 ; 
         FIG. 14  is a schematic illustration of the portion of the seedling handling apparatus of  FIG. 6  in a second position relative to a soil plug; 
         FIG. 15  is a cross-sectional view taken along line  15 - 15 ; 
         FIG. 16  is a perspective view of one example of a plug carrier that is usable with the system of  FIG. 1 ; 
         FIG. 17  is a top view of the plug carrier of  FIG. 16 ; 
         FIG. 18  is a front view of the plug carrier of  FIG. 16 ; 
         FIG. 19  is a cross-sectional view taken along line  19 - 19 ; 
         FIG. 20  is a cross-sectional view taken along line  20 - 20 ; 
         FIG. 21  is a schematic, cross-sectional view of a portion of the system of  FIG. 1 ; 
         FIG. 22  is a flow chart showing one example of a method of processing seedlings. 
     
    
    
     DETAILED DESCRIPTION 
     Various apparatuses or processes will be described below to provide an example of an embodiment of each claimed invention. No embodiment described below limits any claimed invention and any claimed invention may cover processes or apparatuses that differ from those described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention. Any invention disclosed in an apparatus or process described below that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicants, inventors or owners do not intend to abandon, disclaim or dedicate to the public any such invention by its disclosure in this document. 
     As used herein, the term “seedling” refers to a young plant that has developed out of a plant embryo or seed, and includes as an example, a somatic seedling (i.e. a seedling produced via somatic embryogenesis). Each seedling may include a root (e.g. primary root or radicle), the hypocotyl or shoot, the cotyledons (seed leaves or embryonic leaves/needles) and optionally one or more true leaves or needles (secondary needles), depending on the stage of development of the seedling. Seedlings may be of any suitable species of plant, including coniferous or deciduous trees, bushes, shrubs, food crops and the like. For the purposes of this description, each seedling is understood to generally include a root portion that is typically below ground when the seedling is planted (including the radicle), and a stem portion that is understood to include the “non-root” portions of the seedling that are typically above ground when the seedling is planted, including, for example, the shoot/stem/stalk, leaves and needles if any, and the like. 
     As used herein, the term “media”, or growing media, refers to solid or semi-solid material in which a plant embryo, seed or seedling can grow. For example, the media can include soil plugs into which a seedling can be inserted. The soil plugs (also referred to as soil pellets) may be of any suitable type of soil plug and may have any suitable composition. For example, the soil plugs may be made of peatmoss or a peatmoss blend such as a peatmoss/coconut fibre (coir) blend. Optionally, the soil plugs can be stabilized, for example by using a soil stabilization compound and/or polymeric compound, to help provide a desired level of mechanical strength and/or resiliency. Some examples of suitable soil plugs that can be used with the teachings herein include Jiffy-Preforma Plugs or Grow-Tech FlexiPlugs. 
     Referring to  FIGS. 1 and 2 , one example of a system  100  for processing seedlings is shown. The system  100  includes several modules (which may also be referred to here as “systems”, “sub-systems”, “assemblies” and/or “stations”), including an optional washing module  102 , media handling module  104 , seedling handling module  106  and an optional packing module  108 . A controller  122  can be connected to some or all of the modules to control their functions individually (optionally based on some predetermined programming and/or operating parameters and the like), or optionally may be configured to coordinate the operation of two or more of the modules (including as described herein). The controller  122  may be a generally centralized controller, or alternatively may include two or more sub-controllers that are distributed around the system  100 , including some sub-controllers associated with the modules. The controller  122  may include a computer, PLC and any other suitable hardware and/or firmware. 
     The washing station  102  is configured to receive an incoming plurality of seedlings to be processed. In some embodiments, the seedlings may be mixed with growing media (for example from a growing tray in which the seedling was sprouted), debris and other contaminants. To help separate the seedlings from the growing media and debris, the incoming seedlings can be placed into the inlet hopper  110  of the washing station  102 , and then cleaned in the washing section  112 . The cleaned seedlings can then be carried by the exit conveyor  114  and optionally transferred to an intermediary conveyor mechanism that conveys the seedlings to the seedling handling module  106 . Alternatively, the exit conveyor  114  may be directly connected to other portions of the system  100 , eliminating the need for an intermediary conveyor mechanism. The washing station  102  may be of any suitable configuration, and one example of a suitable washing station is a tank with air knives to facilitate separating the seedlings from gel germination media. Alternatively, in some embodiments, the seedlings may be pre-cleaned before being provided to the system  100 , in which case the washing module  102  may not be needed. 
     The intermediary conveyor  116  can be any suitable apparatus that can transport the seedlings to the seedling handling module  106 , for example when used with washing station  102 , it transports the seedlings from the washing module  102  to the seedling handling module  106 . In the illustrated example, the intermediary conveyor  116  includes an upstream conveyor  118  and a downstream conveyor  120 . The conveyors  118  and  120  may be operated at the same speed or, alternatively, may be operated at different speeds. For example, the downstream conveyor  120  may be operated at a faster speed than the upstream conveyor  118  which may help separate and/or space out the seedlings as they travel along the intermediary conveyor  116 . Optionally, the intermediary conveyor  116  may include more than the two conveyors  118  and  120  illustrated. 
     Alternatively, instead of having two or more separate conveyors, the intermediary conveyor  116  may include only a single conveyor belt or an alternative transport mechanism. Optionally, the intermediary conveyor  116  may include moisture module that can be used to help keep the seedlings sufficiently moist as they are transported. This may include a mister or other such mechanism that can spray water or other liquids onto the seedlings, or any other suitable apparatus. Moisture modules may also be provided in some or all of the other modules or stations in the system  100  so that the seedlings are kept sufficiently moist during the entire handling process. 
     In some embodiments, the seedlings provided to the system  100  may be “pre-washed” (i.e. washed in a separate location and/or as part of a separate process). In such embodiments, the system  100  need not include its own washing station  102 , and instead the seedlings may be introduced directly into the seedling handling module  106  or at any other suitable location in the system  100 . 
     Media Handling Module 
     The media handling module  104  can be any suitable apparatus that can receive and handle the growing media into which the seedlings are to be inserted/planted. In the illustrated example, the system  100  is configured to utilize soil plugs, see soil plugs  126  in  FIG. 3  as an example, as the growing media, and the media handling module  104  is configured to receive and manipulate the soil plugs. In other embodiments, the media handling module  104  may be configured to handle a different type of growing media, and may include different handling and transfer mechanisms. 
     In the illustrated example, the media handling module includes an input hopper and feeding module  124  that is configured to receive a batch of soil plugs  126  and to arrange and feed the soil plugs to the rest of the media handling module  104  at a desired rate and in a desired orientation, and the like. One example of a suitable hopper and feeding module  124  is vibratory bowl feeder model 30CWJJ (Feed Rite Automation). In some examples, the hopper portion and feeding portions of the hopper and feeding module  124  may be provided as separate components that are arranged to work together as described. In other embodiments, they may be part of the same apparatus. In some embodiments, the feeding module may include a vibration table that can vibrate the soil plugs  126  and cause them to walk up a ramp/shoot to help ensure they are arranged in a desired orientation as they exit the hopper and feeding module  124 . 
     Optionally, the media handling module  104  can include a pick-up station downstream from the hopper and feeding module  124 , where soil plugs  126  exiting the hopper and feeding module  124  can be collected. The pick-up station may be of any suitable configuration, and may include a table, hopper, conveyor or the like for receiving the soil plugs  126  pending further handling. 
     Referring also to  FIGS. 3-5 , in which portions of the system  100  are illustrated in more detail, with other aspects of the system  100  removed for clarity. As seen in these figures, the media handling module  104  includes a pick-up station  128  that includes a pick-up table  130  for receiving and temporarily holding the soil plugs  126 . The pick-up table  130  may be of any suitable configuration, and in this embodiment is a generally circular, planar table that can rotate about a table axis  132  ( FIG. 4 ). In this arrangement, soil plugs  126  resting on the table  130  can rotate with the table  130  to move through the pick-up station  128 . This may help move the soil plugs  126  into one or more desired pick-up locations and/or may help the system  100  accommodate additional incoming soil plugs  126  on the table  130  when in use. 
     In addition to the pick-up table  130 , the media handling module  104  also preferably includes at least one automated media handling apparatus that can pick up individual ones of the soil plugs  126  and move them to another portion of the system  100  for further handling/processing. Optionally, the automated media handling apparatus can include a robot (such as a multi-axis robot, an articulated robot arm and the like) that can perform a variety of tasks and movements. One example of a suitable robot that can serve as the media handling apparatus is the ABB pick and place robot IRB 910SC-3/0.55. 
     Referring to  FIGS. 3-5 , in the illustrated example the system  100  includes a media handling apparatus in the form of a robot  134  that includes a base  136 , a first linkage  138  that is pivotable relative to the base  136  about a first axis  140 , a second linkage  142  that is pivotable relative to the first linkage  138  about a second axis  144  and an end effector  146  that is operable to pick-up individual soil plugs  126 . The end effector  146  is, in this example a suction gripper that can grip on side of the soil plugs  126  via suction. The end effector  146  is connected to the second linkage  142  via a connector rod  148  that can both rotate about and translate along a third axis  150 . This can enable the end effector  146  to be moved closer to and farther away from the pick-up table  130 , and the rotation can enable the end effector  146  to align the soil plugs  126  in a desired orientation for downstream processing. The robot  134  can be controlled by the controller  122  or any other suitable control mechanism. While one example of the robot  134  has been illustrated, other suitable robots and mechanisms may be used in other embodiments. 
     Preferably, the media handling module  104  can include an automated inspection apparatus that is configured to inspect/analyze the soil plugs  126  that are resting on the soil pick-up table to identify soil plugs  126  that are suitable for further use in the system  100  and, if necessary, identify soil plugs  126  that are damaged, misshapen or are otherwise unsuitable for further use. For example, if a soil plug is  126  broken it may no longer have the desired shape/geometry to be properly handled throughout the rest of the system  100 , or may no longer be of the right size to adequately support a seedling. To help prevent such soil plugs from proceeding through the system  100 , the robot  134  may be operated to pick only acceptable soil plugs  126  from the pick-up table  130 , and to leave any unwanted soil plugs  126  on the pick-up table  130  for removal/disposal. 
     Optionally, the automated inspection apparatus may include any suitable type of sensor or other detection mechanism to inspect and differentiate between the soil plugs  126  on the pick-up table  130 . For example, an automated inspection apparatus may include a camera or other type of optical sensor, a weight or mass based sensor, an IR or light based sensor or the like for determining the condition of the soil plugs  126 . In the illustrated example, the media handling module  104  includes an inspection apparatus having a camera  152  ( FIG. 3 ) that is positioned so that it can see the soil plugs  126  on the pick-up table  130 . The camera  152  can be connected to the controller  122 , for example via wire  154  or wirelessly, which may control the camera  152  and/or may process the images captured by the camera  152 . For example, the controller  122  may include an image processing module that may be operable to, for example, compare the images of the soil plugs  126  to pre-set reference images and to designate a soil plug  126  as being acceptable if it conforms to the reference images (within a given tolerance), and to flag a soil plug  126  as being unacceptable if it does not match the desired reference image. 
     Once designated as acceptable, the system  100  may then track the location of a given soil plug  126  on the pick-up table (optionally via the camera  152  and controller  122 ) so as to be able to direct the robot  134  to pick-up the desired soil plugs  126  and avoid the unwanted soil plugs. 
     Having identified at least one acceptable soil plug  126 , the robot  134  can then be used to grasp the soil plug ( FIG. 3 ), transport the soil plug  126  away from the pick-up table  130  ( FIG. 4 ) and then deposit the soil plug  126  on a subsequent portion of the system  100  for further processing ( FIG. 5 ). 
     In the illustrated example, the system  100  includes a main conveying module  156  that is configured to receive the soil plugs  126  form the media handling module  104  and to convey the soil plugs  126  to the seedling handling module  106  to receive a seedling. The conveying module  156  may have any suitable configuration, and in the illustrated example includes a conveyor track  158  that extends along a conveyor axis  160  and extends from the media handling module  104  to the seedling handling module  106  and terminates adjacent the optional packing module  108 .[0098] 
     In the illustrated embodiment, the conveyor track  158  includes a plurality of plug carriers  162  that are spaced apart from each other along the length of the conveyor track  158  and are configured to removably retain the soil plugs  126  in a desired orientation as they are conveyed along the conveyor track  158 . This may help keep the soil plugs  126  in a desired orientation and in some embodiments, the plug carriers  162  may also help support the soil plugs  126  and reduce the likelihood of a soil plug  126  being damaged during the seedling insertion process and the like. 
     Preferably, the system  100  may also include an apparatus to form a slit/groove in the soil plugs  126  into which a seedling, or at least the root portion of a seedling, can be inserted. This may help facilitate a desired placement of a seedling relative to the soil plug. For example, the system  100  may include any suitable type of plug slitting module that can cut a slit in the soil plugs  126 . The slit may be formed in the soil plugs  126  before they enter the media handling module  104 , or as illustrated in this example, may be formed as the soil plugs  126  are conveyed from the media handling module  104  to the seedling handling module  106 . 
     Referring to  FIG. 4 , in this example conveying module  156  includes a plug slitting module  164  that is positioned above the conveyor track  158  so as to be able to cut a slit in an upward facing surface of the soil plugs  126  as they are held in their respective carriers  162  and conveyed along the conveyor track  158 . In this arrangement, the plug slitting module  164  remains stationary and the soil plugs  126  are translated past the plug slitting module  164  in the direction of axis  160 . Alternatively, the plug slitting module  164  may be movable so that it can be translated relative to a static soil plug  126 , or both the soil plug  126  and the plug slitting module  164  may be movable. 
     Referring also to  FIG. 16 , one example of a plug carrier  162  includes a body  166  that can be secured to the conveyor track  158 , for example by passing fasteners (such as bolts) through respective fastener apertures  168  (see also  FIG. 17 ). 
     The plug carrier  162  includes a central cavity  170  that has a bottom wall  172 , opposing side walls  174 , a front end wall  176  (with reference to the direction of travel of the conveyor track  158 ) and an opposing rear wall  178 . The upper side of the cavity  170  is open to receive a soil plug  126  in a generally vertical insertion direction, as indicated by arrow  180 . 
     Referring also to  FIG. 21 , in the present example, the soil plugs  126  are asymmetrical and have an generally tapered configuration and extend axially along a plug axis  186  between an upper end  182  (with reference to the orientation of the soil plug when planted in the ground) that is larger than the longitudinally opposed lower end  184 . To help accommodate soil plugs of this configuration, the cavity  170  is similarly tapered, with its front end  188  being larger than its rear end  190 , and the side walls  174  taper from front to back. The bottom wall  172  may be inclined (see  FIG. 19 ) to help accommodate the 3D, tapered configuration of the soil plugs  126 . In some embodiments, the plug carrier  162  is suitable for receiving soil plugs  126  with a length of about 43 mm, a maximum width  304  of about 16 mm and a volume of about 12 cc. Other sizes of soil plugs  126  can also be used with plug carriers  162  of different dimensions. 
     Optionally, to help facilitate the placement of the soil plug  126  within the cavity  170  the side walls  174 , and optionally the end walls  176  and  178 , may be tapered in a top/bottom direction, such that the open upper end of the cavity  170  is slightly larger than the bottom wall  172 . 
     Optionally, the plug carriers  162  can be configured so that the soil plugs  126  can be longitudinally slit while being retained within the plug carrier  162 . To help accommodate the activities of the plug slitting module  164 , one or more of the walls bounding the cavity  170  may be sized so as to avoid interference with the plug slitting module  164 , and/or may include one or more relief regions to accommodate the plug slitting module  164 . 
     Referring to  FIGS. 16, 18 and 20 , in the illustrated example the plug carriers  162  include a front relief formed as a gap  192  in the front wall  176  and having gap sidewalls  194  that are laterally spaced apart from each other by a width  196  that is sufficient to accommodate a cutting tool or other such portion of the plug slitting module  164 . A corresponding rear relief is formed as a gap  198  having sidewalls  200  that are spaced apart by a width  202 . Optionally, the width  202  may be the same as, or different than the width  196 . Optionally, the sidewalls  200  may be parallel to and/or co-planar with the sidewalls  194 . The portion of the cavity  170  extending between the gaps  192  and  198  is also generally free of obstructions and/or intervening material, such that a generally clear cutting path is provided between the gaps  192  and  198  to receive the slit cutting tool. 
     For example, referring also to  FIG. 21 , the arrangement of the soil plugs  126  can allow the cutting blade  208  on the plug slitting module  164  to pass through the gaps  192  and  198  and to cut a longitudinally extending slit  210  in an exposed, upper portion of the soil plug  126  as the plug  126  and carrier  162  are translated past the plug slitting module  164  via the conveyor track  158 . 
     In this example, the plug carriers  162  can define a carrier axis  204  ( FIG. 16 ) that extends between the front and rear walls  176  and  178 . When the plug carrier  162  is mounted to the conveyor track  158 , the carrier axis  204  may be at least substantially parallel to the conveyor axis  160 . 
     Optionally, the plug carriers  162  may include an aperture, such as ejection aperture  206  ( FIGS. 17 and 20 ) that can allow an ejection actuator (such as pneumatic actuator, solenoid, blast of compressed air or gas, or the like) to pass through the bottom wall  172  and enter the cavity  170  to mechanically dislodge a soil plug  126  from within the cavity  170 . This may be desired if a defect in the soil plug  126  is noticed after the soil plug has already been positioned within the cavity  170 , or if the soil plug  126  is damaged or otherwise rendered undesirable after having been placed in the cavity  170 . For example, if the slit cutting operation or seedling insertion process damages the soil plug  126 . 
     In the illustrated example, the plug carriers  162  are of integral, one-piece construction and are formed out of acrylic plastic, although they can also be metal. Alternatively, the plug carriers  162  may be formed from more than one piece. 
     After having been conveyed past the plug slitting module  164 , the soil plugs  126 , now including a longitudinally extending slit  210  (see also  FIGS. 14 and 15 ), are conveyed to the seedling handling module  106  to receive a seedling. 
     Seedling Handling Module 
     To help facilitate the inserting of each seedling into a respective soil plug  126 , the system  100  can include any suitable apparatus and/or mechanism that is operable to manipulate the seedlings and insert them in the soil plugs  126 . In some embodiments, all or at least substantially all of the seedling handling can be automated. Alternatively, some aspects of the seedling handling processes described herein may be manually performed by system operators. Optionally, the system  100  may also be configured to automatically inspect the seedlings and identify those that are suitable for planting and those that are not. This inspection may be done at a variety of locations in the overall process described herein, and may be provided in a variety of different modules/portions of the system  100 . For example, the seedlings may be inspected as they enter the washing module  102 , while they are conveyed along the intermediary conveyor  116 , while they are in the seedling handling module  106  and/or after they have left the seedling handling module  106 . 
     Referring to  FIGS. 3-5 , in the illustrated example the seedling handling module  106  is positioned such that it can receive soil plugs  126  being conveyed by the main conveying module  156 , and is downstream from the media handling module  104 . The seedling handling module  106  is also downstream (with reference to the intermediary conveyor  116 ) from the washing module  102 , and is configured to combine the inputs from these modules  102  and  104 . 
     In the illustrated example, the seedling handling module  106  includes a seedling pick-up station  212  that includes a pick-up table  214  for receiving and temporarily holding a plurality of seedlings  216 . As noted herein, each seedling  216  can include a root portion  218  (see also  FIGS. 13-15 ) and a stem portion  220 . The pick-up table  214  may be of any suitable configuration, and in this embodiment is a generally circular, planar table that can rotate about a table axis  222  ( FIG. 4 ). In this arrangement, seedlings  216  resting on the table  214  can rotate with the table  214  to move through the pick-up station  212 . This may help move the seedlings  216  into one or more desired pick-up locations and/or may help the system  100  accommodate additional incoming seedlings  216  on the table  214  when in use. For example, in the illustrated example, the pick-up table  214  includes a receiving region  213  where seedlings  126  are deposited onto the pick-up table, a pick-up region  215  where seedlings  126  are grasped by a suitable pick-up apparatus, and an ejection region  217  where seedlings  126  that are not picked-up can be ejected from the pick-up table  214  (this may help prevent fouling and/or clogging of the system  100 ). These regions may be generally discrete regions on the pick-up table  214 , or may at least partially overlap each other. For example, the pick-up region may  215  may partially overlap one or both of the receiving region  213  and the ejection region  217 . 
     In addition to the pick-up table  214 , the seedling handling module  106  also preferably includes at least one automated seedling handling apparatus that can pick up individual ones of the seedlings  216  and move them to another portion of the system  100  for further handling/processing. Optionally, the automated seedling handling apparatus can include a robot, which may be generally the same as the media handling apparatus  134  or may be a different apparatus. The seedling handling apparatus may be, for example, any suitable multi-axis robot, an articulated robot arm and the like that can perform a variety of tasks and movements. One example of a suitable robot that can serve as the media handling apparatus is the ABB pick and place robot (IRB 910 SC-3/0.55). 
     Referring to  FIGS. 3-5 , in the illustrated example the system  100  includes a seedling handling apparatus in the form of a robot  224  that includes a base  226 , a first linkage  228  that is pivotable relative to the base  226  about a first axis  230 , a second linkage  232  that is pivotable relative to the first linkage  228  about a second axis  234  and an end effector  236  that is operable to pick-up individual seedlings  216 . The end effector  236  is, in this example a suction gripper described in more detail here that can grip the seedlings  216  via suction. The end effector  236  is connected to the second linkage  232  via a connector rod  238  that can both rotate about and translate along a third axis  240 . This can enable the end effector  236  to be moved closer to and farther away from the pick-up table  214 , and the rotation can enable the end effector  236  to align the seedling  216  in a desired orientation when being inserted into corresponding soil plug  126 . The robot  224  can be controlled by the controller  122  or any other suitable control mechanism. While one example of the robot  224  has been illustrated, other suitable robots and mechanisms may be used in other embodiments. 
     Preferably, the seedling handling module  106  can include an automated inspection apparatus that is configured to inspect/analyze the seedlings  216  that are resting on the pick-up table  214  to identify seedlings  216  that are suitable for further use in the system  100  and, if necessary, identify seedlings  216  that are damaged, misshapen or are otherwise unsuitable for further use. For example, a seedling that is lacking a root portion  218  or stem portion  220 , may be unsuitable for inserting in a soil plug  126 . To help prevent such seedlings  216  from proceeding through the system  100 , the robot  224  may be operated to pick only acceptable seedlings  216  from the pick-up table  214 , and to leave any unwanted seedlings  216  on the pick-up table  214  for removal/disposal. For example, suitable seedlings may include a stem portion  220  with a shoot and one or more leaves or needles and a root portion  218  that is for example about 10 mm to about 50 mm in length (e.g. where the radicle is for example between about 10 mm and about 50 mm in length, optionally between about 10 mm and about 40 mm in length). In some embodiments, the size of the lateral roots are also considered. 
     Optionally, the automated inspection apparatus may include any suitable type of sensor or other detection mechanism to inspect and differentiate between the seedlings  216  on the pick-up table  214 . The apparatus may be the same as, similar to or different than the system used to inspect the soil plugs  126 . Optionally, a single inspection system may be used to inspect both the soil plugs  126  and the seedlings  216 , and may be configured to perform all of the functions described herein. Alternatively, the system for inspecting the seedlings  216  may be at least partially separate from the system for inspecting the soil plugs  126 . This may be convenience as each system may then be configured to focus on attributes/features that are unique to the type of object being inspected. 
     For example, an automated inspection apparatus for use in the seedling handling module  106  may include a camera or other type of optical sensor, a weight or mass based sensor, an IR or light based sensor or the like for determining the condition of the seedlings  216 . In the illustrated example, the seedling handling module  106  includes an inspection apparatus having a camera  152  ( FIG. 3 ) that is positioned so that it can see the seedlings  216  on the pick-up table  214 . Optionally, the camera  152  may be positioned so that it sees seedlings  216  locating in the receiving region  213 , but does not inspect seedlings  216  that have moved to the pick-up region  215  or ejection region  217 . This may help facilitate operation of the system  100 , as the camera  152  may have a relatively unobstructed view of the seedlings in the receiving region  213  and its field of view will not be obstructed by the activity of seedling handling apparatus  224 . Alternatively, the camera  152  may be configured so that it can view and inspect seedlings  216  in multiple regions of the pick-up table  214 , and optionally may be configured to view the entire surface of the pick-up table  214 . 
     The camera  152  can be connected to the controller  122 , for example via wire  154  or wirelessly, which may control the camera  152  and/or may process the images captured by the camera  152 . For example, the controller  122  may include an image processing module that may be operable to, for example, compare the images of the seedlings  216  to pre-set reference images or selected parameters and to designate a seedlings  216  as being acceptable if it conforms to the reference images or selected parameters (within a given tolerance), and to flag a seedlings  216  as being unacceptable if it does not match the desired reference image or the selected parameters. For example, the image processing module may use a blob tool to identify seedlings  216 . The identification can comprise one or multiple assessments, for example seedlings  216  that meet an area threshold or range, and/or optionally a color threshold or range, can be identified or further assessed or graded. For example, images of seedlings  216  can first be located in a primary screen and then assessed for area, elongation and/or spread as described for example in Example 1. 
     Once designated as acceptable, the system  100  may then track the location of a given, target seedling  216  on the pick-up table (optionally via the camera  152  and controller  122 ) so as to be able to direct the robot  134  to pick-up the desired seedlings  216  and avoid the unwanted seedlings  216 . 
     For example, after designated as acceptable, the system  100 , optionally via the camera  152  and controller  122 , may identify the position and orientation of the desired seedling  216  by creating a rectangular bounding box that constrains the seedling to determine the angle of the seedling (e.g. the angle of the box in a Cartesian plane) to tell the robot the orientation for pickup. 
     In some embodiments a filter may be used, to help eliminate bright specks or other noise from the image. 
     Seedlings  216  that are not selected for further processing can remain on the pick-up table  214  and travel into the ejection region  217 . The seedling handling module  106  can include an ejection apparatus that is operable to eject the unwanted seedlings  216  from the ejection region  217  so that they do not continue rotating and re-enter the receiving region  213 . The ejection apparatus can include a mechanical pushing or scrapping mechanism that can engage the seedlings  216  travelling on the pick-up table  214 , an air knife or other concentrated blast of air that pushes the seedlings  216  off of the pick-up table  214  and the like. A similar mechanism can be used on the media handling module  104 . Suitable seedlings are optionally identified according to the method provided in Example 1. 
     Suction Tip 
     To pick up a given seedling  216  from the pick-up table  214 , the optionally, the end effector on the seedling handling apparatus, robot  224 , may be any suitable type of manipulator that can grasp and manipulate the seedlings in a desired manner, and preferably without damaging the seedlings or their root structure. For example, the end effector may include a manually gripper or the like. Another example of an apparatus for handling the seedlings is a vacuum or suction based manipulator that can hold, carry and manipulate the seedlings using suction to hold the seedlings in place. Optionally, the end effector can be configured to engage primarily the root portion  218  of the seedling  216 , and may or may not be configured to exert suction on or otherwise engage the stem portion  220  of the seedling  216 . For example, the end effector may be configured to engage the root portion  218  and at least some of the stem portion  220  (for example some of the stem portion  220  that is adjacent the root portion  218 ) and may not directly engage the remainder of the stem portion  220 . 
     Referring to  FIGS. 8 to 11 , one example of a vacuum handling apparatus  242  that can be used as the end effector  236  on the seedling handling apparatus (e.g. robot  224 ) includes a body  244  having an attachment portion  246  that is connectable to a driving member, such as the connector rod  238  of the robot  224 . In this example, the attachment portion  246  includes apertures  247  for receiving a fastener, such as a bolt or screw, but may have other configurations in other embodiments. 
     The apparatus  242  also includes a vacuum channel  248  that has an upper, first end  250  that is configured to be fluidly connected to a suitable vacuum generator, for example via a flexible hose  252 . 
     The opposing end of the vacuum channel  248  is configured as a lower, open tip  254  that is spaced apart from the first end  250  along a channel axis  256 , that is inclined relative to a horizontal plane at an oblique angle  257  ( FIG. 10 ). The channel axis angle  257  may be between about 35 degrees to about 60 degrees, from about 40 degrees to about 55 degrees, about 45 degrees to about 50 degrees or any angle between 35 degrees and 60 degrees, and may be about 45 degrees, about 46 degrees or about 47 degrees. In the illustrated example, the vacuum channel  248  is substantially linear, as is the channel axis  256 . This may help facilitate manufacturing of the apparatus  242  as the vacuum channel  248  may be formed as a generally linear bore, with optional additional machining being conducted at its ends as desired. A linear vacuum channel  248  may also help facilitate air flow through the vacuum channel, which may help reduce backpressure in the vacuum system. Alternatively, the vacuum channel  248  need not be linear, and may be curved or the like. In such embodiments, the channel axis  256  may be defined locally at the upper end  250  and tip  254  as being generally parallel to the direction that air travels through the vacuum channel at that location (i.e. being generally parallel to the flow direction of air through the channel). 
     Referring to  FIG. 10 , the vacuum channel  248  in this example has a hollow channel interior  258  providing fluid communication between the tip  254  and the upper end  250 , and that is bounded by an inner channel surface  260 . 
     The tip  254  of the apparatus  242  is preferably configured to receive some or all of a seedling  216  that is being manipulated, and preferably can help facilitate the pick-up of the seedlings  216  from the pick-up table  214 . The tip  254  may have different configurations in different embodiments (for example to accommodate seedlings of different sizes and/or configurations), but in the illustrated example terminates in a rim  262  that surrounds a tip aperture  264 . The tip aperture  264  may be any suitable shape, including round, and in the present example is a generally oval-like, oblong configuration. Configuring the tip apertures  264  in this manner may help provide a desired flow area/size of the tip aperture  264  while helping to reduce the lateral width  266  of the tip  254  ( FIG. 11 ). As explained in further detail herein, in some embodiments some or all of the tip  254  may be inserted into a soil plug  126  during the seedling insertion process. In such instances, reducing the lateral width  266  of the tip  254  (i.e. at least the portion that is to be inserted within a soil plug  126 ) may help reduce the amount of impact the tip  254  has on the soil plug  126 , and may help reduce the width the slit  210  needs to be opened to receive the seedling  216 . Reducing the width that the slit  210  is spread by the tip  254  may help reduce damage to the soil plug  126 , may help facilitate closing of the slit  210  when the tip  254  exits the soil plug  126  (for example if the soil plug  126  is resilient it may generally self-close if not spread beyond its elastic limits), and may help facilitate stripping of the seedlings from the apparatus  242  by helping to increase the likelihood of engagement between the stem portion  220  and the end face of the soil plug  126  (as described herein). 
     Optionally, the tip  254  can be configured so that the tip aperture  264  lies in more than one plane. That is, the tip aperture  264  may have at least two different regions that are provided in different planes. This may help reduce the likelihood of the aperture  264  becoming completely blocked, for example if pressed against a surface. This may also help increase the chances that a root portion  218  can be drawn into the tip aperture  264  in a variety of orientations. 
     Optionally, the interior  258  of the vacuum channel  248  may be slightly larger toward the tip  254  than it is toward the upper end  250 . This may help facilitate sucking the root portion  218  into the tip  254 , and may help facilitate sucking the root portion  218  into the tip  254  in a wider variety of alignments/orientations of the apparatus  242  relative to the seedling  216 . For example, the robot  224  may be operated such that when attempting to grasp a seedling  216  the apparatus  242  is rotated about axis  240  so that the vacuum channel  248  is generally aligned with the direction the root portion  218  of the seedling  216  is extending. However, in some instances the root portion  218  may have a non-linear arrangement or the apparatus  242  may not be exactly aligned with the root direction. In such instances, providing a relatively wider/larger tip aperture  264  may help facilitate the desired engagement and capture of the root portion  218 . This arrangement may also help facilitate engagement of the root portion  218  if the apparatus  242  contacts the root portion  218  at various locations along its length. Preferably, the apparatus  242  can be positioned adjacent the tip of the root portion  218  of a given seedling  216 , and the vacuum suction can draw the root portion  218  longitudinally into the channel interior  258 . In other instances, the tip  254  may engage a root portion  218  at an intermediate location (i.e. somewhere between its free tip and the stem portion  220 ). Providing a tip  254  with a rim  262  and tip aperture  264  as described herein may, in some embodiments, help increase the likelihood that a root portion  218  engaged in such an intermediate location will be sucked into the channel interior  258 . 
     Referring to  FIG. 10 , in the illustrated example, the tip  254  is configured such that the rim  262  has a first portion  274  that lies in a first plane  276  and a second portion  278  that lies in a second plane  280  that is not parallel to the plane  276 , and intersects plane  276  at an oblique intersection angle  282 . The intersection angle  282  may be for example from about 35 degrees to about 60 degrees, from about 40 degrees to about 55 degrees, about 45 degrees to about 50 degrees or any angle between 35 degrees and 60 degrees such as about 45 degrees, about 46 degrees, about 47 or about 48 degrees. In this example, the rim  262  is configured such that the line of intersection of the planes  276  and  280  is offset from (i.e. is not intersected by) the channel axis  256 , and that the channel axis  256  is generally orthogonal to the plane  276 . This may help provide the desired tip  254  configuration described herein. 
     Preferably, the tip aperture  264  can be sided to generally freely receive the root portion  218  of a seedling  216 , such that the root portion  218  can be relatively easily sucked into the vacuum channel  248  and relatively easily removed from the vacuum channel  248  when desired. That is, when the apparatus  242 , and specifically the tip  254  is positioned proximate the root portion  218  of a seedling  216  on the pick-up table  214  and vacuum is applied to the vacuum channel  248  the root portion  218  will be sucked into the channel interior  258 . The tip aperture  264  is also sized so that its flow area (i.e. a cross-sectional area taken in a plane that is generally orthogonal to the direction air flows into the channel interior  258 —i.e. orthogonal to the channel axis  256  in this example) is smaller than the expected size of the stem portion  220  of the seedlings  216  to be manipulated. Sizing the tip apertures  264  to be smaller than the stem portion  220  may help prevent the seedlings  216  from being completely sucked inside the vacuum channel  248 . For example, in the present embodiment, the root portion  218  may be sucked into the vacuum channel  248  until a non-root portion of the seedling  216  contacts and abuts the rim  262  (and/or surrounding portions of the tip  254 ). When the non-root portion abuts the rim  262  further movement of the seedling  216  into the vacuum channel  248  may be inhibited and/or prevented. That is, when a seedling  216  is fully seated within the apparatus  242 , the root portion  218  may be contained within the vacuum channel  248  while at least some of the non-root portion remains exposed and external the vacuum channel  248 . For example, the seedlings  216  may be drawn into the vacuum channel  248 , and optionally at least a portion of the stem portion  220  may also be drawn into the vacuum channel  248 , until there is contact between some of the stem portion  220  and the rim  262 . In some embodiments, parts of the stem portion  220  that are adjacent the root portion  218  and have a similar size may be drawn into the vacuum channel  248  until other, generally wider parts of the stem portion  220 , such as the leaves and/or needles and the like, abut the rim  262  and restrain the movement of the seedling  216 . In such an arrangement, movement of the seedlings  216  into to the suction channel  248  can be referred to as being inhibited by engaging the stem portion  220 , even though some parts of the stem portion  220  are in fact received within the suction channel  248 . A similar understanding applies when discussing stripping of the seedlings  216  from the suction channel  248 , inserting the seedlings  216  into the soil plugs  126  and the like. For example, there may be engagement between an end face of a soil plug  126  and the stem portion  220  of a seedling  216 , such as the leaves or needles, even if part of stem portion  220  (i.e. some of the non-root material) is actually received inside the soil plug  126 . 
     In the illustrated example, the vacuum channel  248  includes a generally narrowing throat portion  268  ( FIG. 10 ) that separates a relatively larger region  270  of the interior from a relatively smaller region  272 . The throat portion  268  is illustrated as being closed to the tip  254  than the upper end  250 , but may be in other locations in other embodiments. The relatively larger region  270  may also help facilitate a desired level of air flow around the root portion  218  (when a root portion  218  is received in the tip  254 ) which may help prevent choking or throttling of the vacuum channel  248 , and may in some instances help prevent the root portion  218  from blocking air flow through the vacuum channel  248  an being subjected to the blockage/break suction force. 
     Having picked-up a target seedling  216  to be planted, the robot  224  can move the end effector  236 , including apparatus  242 , into an insertion location, in which the apparatus  242  is positioned above a corresponding soil plug  126  (held in a carrier  162  on the conveyor track  158 . To deposit the seedling  216  into the soil plug  126 , a portion of the tip  254 , and optionally the entire tip  254 , can be inserted into the soil plug  126 . The tip  254  can then be used to help spread open the slit  210  in the upper side of the soil plug  126  so that the seedling  216  can be placed in the interior of the soil plug  126 . When the tip  254  is removed from the slit  210 , the resilient nature of the soil plug  126  (or an external closing force) may tend to urge the slit  210  closed, thereby enclosing the root portion  218  of the seedling  216  within the soil plug  126 . 
     The tip  254  may have any suitable configuration to help facilitate the seedling  216  insertions, and one example of the tip  254  design is shown on the apparatus  242  of  FIGS. 6-11 , and its use when inserting a seedling in a soil plug is schematically illustrated in  FIGS. 12-15 . In this example, in addition to the tip aperture  264 , the tip  254  includes a generally wedge-like ploughshare portion  284  that is positioned adjacent the tip aperture  264  and located such that it will lead (i.e. travel in advance of) the tip aperture  264  if the apparatus  242  is translated relative to a soil plug  126  with the tip  254  inserted in the soil plug  126  (i.e. from right to left as illustrated in  FIGS. 10 , and  12 - 15 ). With reference to the direction of translation of the apparatus  242 , the ploughshare portion  284  can be considered to be forward of the tip aperture  264 . 
     The ploughshare portion  284  is intended to extend into the slit  210  in the soil plug  126  and to be translated along the length of the slit  210  to help spread/open the slit  210  in advance of the arrival of the tip aperture  264  and the seedling  216  held therein. The ploughshare portion  284  may have any suitable configuration, and in the illustrated example is a generally tapered, wedge-like member that has a base  286  adjacent the lower tip  254 , and tip aperture  264 , and a leading edge  288  narrower than and that is spaced forwardly from the base  286  by a ploughshare length  290 . In this example, the ploughshare portion  284  generally tapers from the base  286  to the leading edge  288 . Referring to  FIG. 11 , the base  286  of the ploughshare portion  284  has the same width  266  as the tip  254 . In other embodiments the ploughshare portion  284  may have a different configuration. 
     To insert a seedling  216 , the tip  254  and ploughshare portion  284  are inserted into the slit  210 , and the apparatus  242  is translated axially relative to the soil plug  126  (or vice versa).  FIGS. 12 and 13  illustrate the apparatus  242  toward the beginning of the insertion process, in which the leading edge  288  of the ploughshare portion  284  is beginning to engage and widen the slit  210 , while the tip  254  and seedling  216  remain spaced from the soil plug  126 . Optionally, the apparatus  242  can be maneuvered such that the ploughshare portion  284  is vertically inserted into the slit  210 , or so that the ploughshare portion  284  is positioned at the desired elevation and then translated horizontally to engage the slit  210 . 
     As the insertion process advances, the apparatus  242  is translated along the length of the soil plug  126 , whereby the ploughshare portion  284  continues to open the slit  210  and the tip  254  moves into engagement with the soil plug  126 . 
     To help transfer the seedling  216  from the apparatus  242  to the soil plug  126  the seedling  216  can be stripped from the vacuum channel  248 . In some embodiments, the apparatus  242  may include a stripping apparatus that can extract the seedling  216  from the vacuum channel  248 . For example, a mechanical gripper or the like may be used to manually extract the seedling  216  from the vacuum channel  248 . Alternatively, the pressure in the vacuum channel  248  may be reduced, such that pressurized air is introduced into the channel  248  to blow the seedling  216  out of the channel  248 . Optionally, pressurized air may also be blown through the vacuum channel  248  while the channel  248  is empty. This may be used to help clean the vacuum channel  248  and dislodge any debris that may accumulate within the vacuum channel  248 . Optionally, this pressurized air cleaning step can be conducted after each seedling insertion, after a pre-determined number of seedling insertions (such as after every 10, 100 etc.), at another desired frequency and/or manually upon user input. 
     In yet other embodiments, the seedling  216  may be stripped from the vacuum channel  248  by engagement with an external surface or apparatus. 
     In the illustrated example, the tight fit between the tip  254  and the slit  210  may open the slit  210  to a width that is wider than the root portion  218  (e.g. at least the radicle) of the seedling  216 , but is less than a width/area of the stem portion comprising leaves and/or needles  220 . In this arrangement, the tip  254  and seedling  216  may move through the interior of the soil plug  126  together until the stem portion  220  comes into contact with the end face  292  at the upper end  182  of the soil plug  126 . When the stem portion  220  abuts the end face  292 , translation of the seedling  216  through the slit  210  can be inhibited. As the apparatus  242  continues to translate, the root portion  218  is extracted from the vacuum channel  248  and is deposited within the slit  210 . When the apparatus  242  is moved such that the root portion  218  is completely removed from the vacuum channel  248 , as shown in  FIGS. 15 and 16 , the tip  254  can be withdrawn from the soil plug  126  leaving the seedling  216  behind. 
     Using the engagement between the stem portion  220  and the soil plug  126  to strip the seedling  216  from the apparatus  242  can help accommodate for variations in seedling sizes, roots lengths, stem configuration and the like. 
     Optionally, the apparatus  242  may include more or more additional bearing surfaces that are intended to contact the soil plug  126  during the insertion process. For example, the apparatus  242  may contact the soil plug  126  to help keep the soil plug in position while the tip  254  and ploughshare portion  284  are being dragged through the slit  210 . In the illustrated example, the apparatus  242  includes a flared, base surface  294  that is generally downward facing when the apparatus  242  is in use, and lies in a plane  296  ( FIG. 10 ) which, in this example, is parallel to and offset from the plane  280 . 
     The base surface  294  is positioned such that the tip  254  and ploughshare portion  284  extend beyond the base surface  294  by a desired depth  298  ( FIG. 11 ). The depth  298  can be selected so that the base surface  294  can bear against (or at least be closely offset from) an upward facing surface  300  of the soil plug  126  ( FIGS. 12 and 15 ). In some instances, the tip depth  298  may be equal to, or optionally less than, the depth of the slit  210 . 
     The base surface  294  also has a width  302  ( FIG. 7 ) that can be selected so that it is equal to or greater than a maximum width  304  ( FIG. 14 ) of the soil plug  126 , or alternatively may be less than the plug width  304 . In some embodiments, the width  302  of the base surface may be about 12, about 13, about 14, about 15, about 16, about 17 or about 18 mm. 
     Preferably, the apparatus  242  is configured so that the base surface width  302  is greater than the tip width  266  ( FIG. 11 ), and may be configured so that the tip width  266  is between about 5% and about 25% (i.e. less than 25%) of the base surface width  302 , and may be between about 10% and about 20% or between about 12% and about 16% of the width  302 , and may be about 15% of the width  302 . 
     Optionally, the apparatus  242  may include an inclined ramp surface  306  positioned where the leading edge  288  of the ploughshare portion  284  meets the rest of the body ( FIGS. 9 and 10 ). The ramp surface  306  may be inclined relative to the plane  296  and may help inhibit soil and other debris from accumulating on the apparatus  242 , and in some embodiments may help prevent the apparatus  242  from snagging or otherwise damaging the soil plugs during the insertion process. 
     Optionally, the base surface  294  can include an overhanging shelf portion that can extend rearwardly (relative to the direction of translation of the apparatus  242 ) beyond the tip  254  and overhang the stem portion  220  of a seedling  216  being carried. This may help inhibit portions of the soil plugs  126  and/or portions of the seedlings  216  carried in the apparatus  242  from curling up and/or wrapping upwardly around the trailing edge of the tip  254 . For example, if a stem portion  220  of a seedling  216  were to curl substantially upwardly, the stem portion  220  could arrive at a position where it is above the slit  210  in the soil plug  126 . In such a configuration, the stem portion  220  may fail to engage the end face  292  of the soil plug  126 , thereby inhibiting stripping of the seedling  216  from the vacuum channel  248 . This could result in the seedling  216  being pulled completely through the soil plug  126  and failing to remain inserted in the plug. In the illustrated embodiment, the base surface  294  includes a shelf portion  308  that extends rearwardly of the tip  254  by an offset length  310 . 
     Optionally, the seedling handling apparatus, e.g. robot  224  can have a seedling pick rate “P” that can be expressed in number of seedlings that can be picked and inserted into corresponding soil pods within a given time period, such as one minute. For example, the seedling handling apparatus may be operable to pick and insert about 20 to 60 seedlings per minute. 
     Optionally, the rotation of the pick-up table may be coordinated with the seedling handling apparatus, for example by configuring the controller accordingly. For example, it may be desirable in some embodiments that a given seedling only travel on the pick-up table for one revolution, before being ejected. This may help the system  100  operate a desired production rate. That is, a batch of seedlings, containing n seedlings may be deposited in the deposit region of the pick-up station, and may rotate with the pick-up table. The system can optionally be configured so that the pick-up table rotates slowly enough such that if each of the n seedlings is identified as being acceptable for inserting in a soil pod, the seedling handling apparatus will have enough time to pick and insert each seedling before the seedlings reach the ejection region. To help provide sufficient time for the seedling handling apparatus to pick each seedling, the pick-up table may be rotated at a rate that is less than or equal to n/P revolutions per minute. For example, if 30 seedlings are provided on the pick-up table and if the seedling handling apparatus has a picking rate P of 60 seedlings per minute, the pick-up table can rotate at a speed of up to about 2 rpm or less to and still allow sufficient time for the seedling handling apparatus to pick all of the seedlings before they reach the ejection region. 
     While described with reference to the seedling handling module  106 , the media handling module  104  may have an analogous configuration, based on a pick-rate of the media handling apparatus. 
     While illustrated as separate modules in the present example, in other embodiments of the system  100  the mechanism for cutting slits (e.g. plug slitting module  164 ), or other suitable formations, in the soil plugs  126  may be provided as part of the seedling handling module  106 , and optionally may be mounted on and may be movable with the end effector  236  of the robot  224 . For example, an end effector may be configured to include a cutting mechanism positioned such that it would lead the ploughshare portion when the end effector  236  is translated relative to a soil plug  126 . In such an arrangement, the soil plug  126  may be slit and receive a seedling  216  in what is effectively a single step in the process. In other embodiments, the system  100  need not include a separate plug slitting module  164 , but instead the end effector  236  may be used to insert a seedling  216  into a soil plug  126  that has not been pre-slit. This may not be desirable in some circumstances, as it may tend to damage the soil plugs  126 . 
     Packaging Module 
     After the seedlings  216  have been received in respective soil plugs  126 , the soil plugs  126  can be further conveyed by the conveyor track  158  to the packing module  108 . The packing module  108  may optionally include an automated packing apparatus that can pick the soil plugs  126  out of their carriers  162  and insert the soil plugs  126  into a container or tray for further processing and/or shipping to a customer. 
     Referring to  FIGS. 3-5 , In the illustrated example, the packing module  108  includes an automated, gantry style robot  312  (such as a Linear axis apparatus model: EGC-80-600 (Festo) that has an end effector in the form of a mechanical gripper  314 , with opposing, movable tines  316  for grasping the outer surface of the soil plug/seedling combinations. In the illustrated example, the soil plugs  126  are arranged generally horizontally in their carriers  162 , and the robot  312  has at least one pivot axis  318  that can allow the gripper  314  to pivot about 90 degrees. This can allow the gripper  314  to grasp the soil plugs  126  in their generally horizontal arrangement ( FIG. 5 ) and to deposit the soil plugs  126  into a corresponding cavity  320  in a holding tray  322  in a generally vertical orientation (i.e. with the stem portion  220  above the root portion  218 — FIG. 4 ). Optionally, either the tray  322 , robot  312  or both can be movable to allow the gripper  314  to deposit soil plug/seedling combos into each cavity  320  in the tray  322 . When the tray  322  is full, it may be moved for further processing and another tray  322  provided. 
     Referring to  FIGS. 16, 17 and 19 , the carriers  162  may be configured to help facilitate gripping and removal of the soil plugs  126  using the gripper  314 . In this example, in addition to the front and rear relief gaps  192  and  198 , the sidewalls  174  of the carriers  162  may also include a generally laterally extending gripper relief channel  320  that is sized to receive the tips of the tines  316  on the gripper  314 . This can help allow the gripper  314  to grasp the side surfaces of the soil plugs  126  without grasping or otherwise interfering with the carrier  162 . 
     Referring to  FIG. 22 , one example of method  500  of processing/handling seedlings and specifically for inserting the seedlings in soil plugs. In this example, the method can include the step of, at step  502 , automatically identifying a target seedling located in a pick-up area using any suitable seedling detection/inspection apparatus (including those described herein). The method can also include picking-up the target seedling with an automated seedling handling apparatus (step  504 ) and transporting the target seedling to an insertion area (step  506 ), which can be a portion of the seedling handling module  106  or any other suitable location. The system can then, at step  508 , provide a first soil plug in the insertion area, for example from the media handling module  104 , to receive the target seedling. 
     Step  510  can then include spreading the slit in the first soil plug, and step  512  can include inserting a root portion of the seedling into the slit while a stem portion of the seedling is positioned outside the first soil plug. 
     With the root portion nested with the soil plug, the method can proceed to step  514  that includes stripping the target seedling from the handling apparatus whereby the seedling remains received within the slit in the first soil plug. 
     The method  500  may also include a number of optional steps (as indicated by dashed lines), including step  516  that includes closing the slit around the root portion of the target seedling to enclose the root portion within the first soil plug. Optionally, the method can include step  518  that can be performed before step  502  and can include receiving a plurality of seedlings from a growing station and washing the plurality of seedlings to remove excess growing material at a washing station before the plurality of seedlings are positioned in the pick-up area. 
     Having completed step  514 , the combination of the first soil plug and the first seedling can be transferred to an optional a packing station at step  520  and automatically packing the first soil plug containing the first seedling into a holding tray using an automated packing apparatus. 
     EXAMPLES 
     Example 1 
     Identifying a Target Seedling Located in a Pick-Up Area Using Seedling Detection Apparatus 
     A machine vision camera, such as the In-Sight® vision system by Cognex Corporation is used in order to locate and grade seedlings as they come into view. The In-Sight vision system software, In-Sight Explorer® allows various parameters to be determined and set based on the desired objects, here seedlings, to be selected. The parameters are selected for example by trial and error and selected according to desired criteria specificity. Preselected seedlings were used to determine suitable ranges for parameters used for selection and grading for example such us as elongation and area, and optionally spread. The settings are selected to reduce the misidentification of debris such as growth gel that may be present in the field and maximize the identification and selection of seedlings. Once the seedlings are found and graded, the best candidate from each image is chosen, and its coordinates are sent to the robot for picking. Each cycle, a new image is taken. An exemplary process using the In-Sight vision system and Explorer software is described below: 
     1. Each cycle, the camera will take an image. From this image, assuming there are seedlings present, a blob tool is used to select each seedling in the image, up to 30 total. A blob is defined, in this case, of any grouping of touching pixels. Any pixels above the selected colour threshold will cause a discontinuity in the blob. Pixels are evaluated according to the scale below. Criteria used can be:
         a. Area: Between 750 and 13,000 pixels   b. Color: up to 200 grayscale, out of a maximum of 255 where 0 is black and 255 is white       

     2. Once the seedlings are found, they can be graded using the following criteria:
         a. Area: Blobs between 2000 and 4000 pixels are accepted (including the root and needles)   b. Elongation: An elongation between 0.5 and 4.5 is used. Elongation is a determination of how ‘stretched’ the pixels are from the center of mass (determined from the centroid of the blob). For example, circle would have 0 elongation whereas a long thin line has a high elongation   c. Spread: Spread is optional. This is a measure of how the pixels are spread out from the centroid. For example, an oval has a greater spread than a circle.       

     3. Based on step 2 above, the best graded seedling is selected. After selection, a rectangular bounding box is created that completely constrains the seedling. This determines the angle of the seedling (angle of the box in a Cartesian plane to tell the robot the orientation for pickup), as well as the general size. Also, an ‘Erode’ filter is used, to help eliminate any bright specks or noise from the image. 
     4. To accurately determine the pick location on the root of the seedling, 6 rectangular regions are created inside the bounding box, approximately ¼″ from the bottom of the bounding box (other locations can also be used). Once each region is created, a Histogram tool is used within. This tool grades the average pixel color. 
     5. Once all of the Histograms are performed, the region with the lowest pixel color (e.g. region with the darkest area, and typically for example less than 200) is selected as the candidate where the root resides. From this, another Blob tool is used. The centroid coordinate from this resultant blob is used for the pick point sent to the robot. With this coordinate, as well as the above described angle, the robot is able to correctly pick up the seedling. 
     What has been described above has been intended to be illustrative of the invention and non-limiting and it will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto. The scope of the claims should not be limited by the preferred embodiments and examples, but should be given the broadest interpretation consistent with the description as a whole.