Patent Publication Number: US-2021181078-A1

Title: Rapid stalk strength assessment

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage of International Application No. PCT/US2019/034602, filed May 30, 2019, which claims the benefit of U.S. Patent Provisional Application No. 62/679,179 filed on Jun. 1, 2018. The disclosure of the above applications are incorporated herein by reference in their entirety. 
    
    
     FIELD 
     The present teachings relate to the testing of corn stalk strength testing for plant breeding programs, and particularly to post-harvest systems and methods for evaluating the pre-harvest strength of a corn plant stalk. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     Stalk strength is crucial to preventing lodging in maize (corn plants). Unfortunately, accurate and reliable scoring of stalk strength is difficult as the trait does not manifest in an external and easily visible way. A common used method to assess stalk lodging has been a field-count method where lodged plants are counted at harvest, thereby placing plants into two categories: lodged or standing. This field-count method generated stalk lodging percentages that satisfactorily served corn breeders in efforts to improve stalks by identifying germplasm most likely to lodge. However, as stalk strength of germplasm improved, additional progress using the field-count method became increasingly difficult, in part, because it is highly dependent on environmental conditions that do not occur at a frequency consistent enough to assure continued progress among germplasm with increasingly stronger stalks. 
     Hence, a variety of additional methods that are correlated with stalk lodging but are less affected by environmental fluctuations were evaluated and used to measure stalk strength as related to lodging potential. These methods included measures such as: breaking strength of internodes, crushing strength of excised stalks segments, thickness of stalk rind tissues, rind puncture measurements using rind penetrometers, stalk diameter measurements, internode length measurements, three-point bending and load bearing assessments, stalk flexural stiffness, elliptical section modulus, lignification of stalk tissues, density of pith tissues, water content in stalk and pith tissues, soluble solids in stalks, specific gravity of stalk tissues, stalk push tests, stalk pinch test, and assessments of fungal stalk rots. Additionally, some current methods for assessing stalk strength include sensors that are pressed against the stalk and/or devices that blow air against the stalk to determine how much force is needed to cause lodging. 
     Most of these methods require a laboratory and/or controlled conditions to measure the strength of stalks so the data they generate are independent of the environmental forces that affect lodging. Additionally, they require sampling of stalks during the reproductive period of grain-fill or measurements taken on stalks sampled before or at harvest. More particularly, aside from the lack of accuracy and scientific reproducibility, current methods of assessing stalk strength are based on the idea that if one desires to assess a corn stalk at the strongest point in its life cycle, it is necessary to test the stalk&#39;s strength when the plant is at that stage of its life cycle. In other words, if a breeder wants to score stalks for stalk strength, they need to conduct their stalk strength tests while the plants are growing, generally in the middle or last half of the life of the plant (e.g. while the corn plant is flowering or during grain fill). Furthermore, because current methods typically involve pressing a hand or sensor (e.g. the push test) or forcing air against the stalk until the stalk lodges and/or breaks, these methods usually kill or disrupt the plant&#39;s development so much that it is unusable for further scientific testing (e.g. collecting yield data). 
     SUMMARY 
     Plant refuse remaining in fields after a corn crop has been mechanically harvested with a combine is typically considered to be trash, and only useful as animal bedding or other purposes not directly-related to food production. There are generally two major components of corn harvest refuse: 1) plant materials such as leaves, stalks, tassels, husks, cobs, light-weighted grain, etc., that pass through the combine and are then deposited on the ground as chopped or cut pieces of various sizes after being separated from corn grain that is retained in the combine, and 2) corn stalk stumps which consists of the lower stalks and roots that pass under the combine when the combine head cuts and collects the upper portions, e.g., three-quarters, of the corn plant from which the grain is harvested. The amount and length of corn stalk stumps depends on the height at which the combine head is operated which varies within and among fields. The concept that corn stalk stumps have informational value as an alternative method to measure the potential of stalk lodging has not been realized previously, i.e., methods to assess stalk lodging have not been done utilizing post-harvest stalk stumps that remain after the combine has harvested the desired portion of the plants. 
     Disclosed herein is a discovery that the stalk strength of a corn plant, pre-harvest, during flowering and/or seed production, as measured by a “push test”, are highly correlatable to certain types of cross-section analysis conducted post-harvest at the end of the plant&#39;s life on the discarded stalk stumps that are left in the field after harvesting (e.g., the refuse or stubble of the corn plants that is typically discarded). These methods enable accurate estimation of what a corn stalk&#39;s strength was an different points of the plant&#39;s life cycle (e.g. during grain fill) by analyzing the pith and/or rind of the stalk in cross-section after of its life cycle (e.g. post-harvest analysis of the discarded stalk stumps). Thus, plant breeders no longer need to disturb or halt a corn plant&#39;s growth and/or development with mechanized tests to score the plants for stalk strength. Rather, the plants can be allowed to mature normally, so they are still scientifically valid subjects for other experimental comparisons throughout the plant&#39;s life (e.g. yield, disease resistance, etc.). 
     In various embodiments, after or at substantially the same time as the corn plants have been harvested the exposed pith and/or rind of the discarded stalk stumps are viewed and/or imaged, analyzed and scored on its integrity, e.g. scored or rated based on empty spaces around the pith/rind or deterioration of the pith/rind tissue. The greater the spaces and/or deterioration of the pith/rind, that is the lower the integrity of pith/rind, the lower the resulting score will be. The scores are then translated into a stalk strength score for each plant at a pre-harvest growth stage (e.g., R6 or later), whereby a breeder can use the scores when making breeding decisions. In various embodiments, a device or system can be used to cut the post-harvest stalk stumps growing in a field to provide a substantially clean and smooth cross-section (at any desired angle) prior to viewing and/or imaging the pith and/or rind. 
     Although this disclosure is not limited to certain method(s) of creating the cross-section, nor how the cross-section is scored (e.g. manually, with electronic optical/visual analysis equipment, etc.), the following are general descriptions of various exemplary embodiments. 
     In various embodiment, post-harvest discarded stalk stumps are cut or severed (e.g., cut or severed between the second and third internode) with a stalk stump cutter, e.g., a saw, knife, combine chopping head etc., optionally mounted to and suspended from a mobile platform that is capable of traversing the growing area (e.g., the field in which the stalk stumps have grown). The saw can be arranged on the mobile platform such that, as the mobile platform moves over or alongside a row of stalk stumps protruding out of the ground (or alternatively a row of corn plants), the stalk stump cutter rapidly cuts or severs the discarded stalk stumps (or corn plants) at substantially the same height to provide a substantially clean and smooth cross-section (at any angle), and expose the piths/rinds at a high throughput rate (e.g., 1-3 stalks per second). 
     In various embodiments, the discarded stalk stump cross-sections are scored by the human eye, or with an electronic camera mounted to a mobile platform capable of traversing the field. In various instances, the camera can be configured to automatically and rapidly capture images of the cross-sections of the discarded stalk stumps (e.g. 1-3 plants per second), whereafter the image data can be analyzed by a computer based data processing system that can be remotely located separate from the other components of the system, or locally located and/or combined with any one or more of the other components of the system. 
     In various embodiments, plant and other debris in and/or around the discarded stalk stumps can be removed to facilitate visual or image data scoring. For example, in various embodiments a blower that uses forced air to move debris away from the stalk stumps can be used, thereby providing a background of substantially bare earth substantially free of plant debris. This permits the system to more accurately distinguish the pith/rind of the stalks and improve stalk integrity assessment. 
     It is envisioned that the system(s) of the present disclosure can be fully-automated, capable of using electronic geo-location to perform all of the activities necessary to assess the stalk integrity of thousands or more plants per hour, thereby providing plant breeders with accurate and high-throughput system(s) and method(s) of estimating the pre-harvest stalk strength, for example during the grain fill period, for a plurality of corn plants without damaging the plants until after or during harvest. The stalk strength data obtained by the system(s) and method(s) described herein can be combined with other types of data collected about the plants&#39; performance (e.g. yield, disease resistance) to provide plant breeders a highly-accurate, high-throughput method of assessing overall crop performance. 
     This summary is provided merely for purposes of summarizing various example embodiments of the present disclosure so as to provide a basic understanding of various aspects of the teachings herein. Various embodiments, aspects, and advantages will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. Accordingly, it should be understood that the description and specific examples set forth herein are intended for purposes of illustration only and are not intended to limit the scope of the present teachings. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present teachings in any way. 
         FIG. 1  is a schematic of a post-harvest stalk strength determination system, in accordance with various embodiments of the present disclosure. 
         FIG. 2  is a schematic of the post-harvest stalk strength determination system shown in  FIG. 1 , in accordance with various other embodiments of the present disclosure. 
         FIG. 3  is an exemplary front isometric illustration of the post-harvest stalk strength determination system shown in  FIG. 1  having the various components thereof mounted to a walk-behind mobile platform, in accordance with various embodiments of the present disclosure. 
         FIG. 4  is an exemplary rear isometric illustration of the post-harvest stalk strength determination system shown in  FIG. 3  having the various components thereof mounted to a walk-behind mobile platform, in accordance with various embodiments of the present disclosure. 
         FIG. 5  is an exemplary front illustration of the post-harvest stalk strength determination system shown in  FIG. 3  being used in a field, in accordance with various embodiments of the present disclosure. 
         FIG. 6  is an exemplary illustration of a plurality of substantially flat and even prepared cross-sections of various stalk stumps provided using the post-harvest stalk strength determination system shown in  FIGS. 1 through 3 , in accordance with various embodiments of the present disclosure. 
         FIG. 7  is an exemplary isometric illustration of the post-harvest stalk strength determination system shown in  FIG. 1  having the various components thereof mounted to a corn harvester mobile platform, in accordance with various embodiments of the present disclosure. 
         FIGS. 8A and 8B  are exemplarily schematics of the post-harvest stalk strength determination system shown in  FIG. 3  wherein an example sensor system capable of detecting and differentiating healthy vs. unhealthy piths of post-harvest corn stalk stumps is deployed on a combine harvester, permitting simultaneous harvest and stalk health image and/or data collection, in accordance with various embodiments of the present disclosure. 
         FIG. 9  exemplarily illustrates three examples of how the post-harvest stalk strength determination system show in  FIGS. 1 through 3, 7 and 8  deployed on a 4-row combine harvester with onboard stalk pith-analysis capabilities, can be used to harvest research plots in a corn field at the same time it is used to collect data and/or images of corn stalk stumps, in accordance with various embodiments of the present disclosure. 
         FIG. 10  exemplarily illustrates the results of a 2016 leaf-stripping-induced carbohydrate stress trials at Waterman, Ill. and Evansville, Ind., in accordance with various embodiments of the present disclosure. 
         FIG. 11  exemplarily illustrates the correlations of means of the 58 hybrids common to two sets of trials in the 2016 trials at Waterman, Ill. and Evansville, Ind., in accordance with various embodiments of the present disclosure. 
         FIG. 12  exemplarily illustrates the results of a 2017 leaf-stripping-induced carbohydrate stress trials at Waterman, Ill., in accordance with various embodiments of the present disclosure. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of drawings. 
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is in no way intended to limit the present teachings, application, or uses. Throughout this specification, like reference numerals will be used to refer to like elements. Additionally, the embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art can utilize their teachings. As well, it should be understood that the drawings are intended to illustrate and plainly disclose presently envisioned embodiments to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views to facilitate understanding or explanation. As well, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention. 
     As used herein, the word “exemplary” or “illustrative” means “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” or “illustrative” is not necessarily to be construed as preferred or advantageous over other implementations. All of the implementations described below are exemplary implementations provided to enable persons skilled in the art to practice the disclosure and are not intended to limit the scope of the appended claims. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps can be employed. 
     When an element, object, device, apparatus, component, region or section, etc., is referred to as being “on,” “engaged to or with,” “connected to or with,” or “coupled to or with” another element, object, device, apparatus, component, region or section, etc., it can be directly on, engaged, connected or coupled to or with the other element, object, device, apparatus, component, region or section, etc., or intervening elements, objects, devices, apparatuses, components, regions or sections, etc., can be present. In contrast, when an element, object, device, apparatus, component, region or section, etc., is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element, object, device, apparatus, component, region or section, etc., there may be no intervening elements, objects, devices, apparatuses, components, regions or sections, etc., present. Other words used to describe the relationship between elements, objects, devices, apparatuses, components, regions or sections, etc., should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). 
     As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, A and/or B includes A alone, or B alone, or both A and B. 
     Although the terms first, second, third, etc. can be used herein to describe various elements, objects, devices, apparatuses, components, regions or sections, etc., these elements, objects, devices, apparatuses, components, regions or sections, etc., should not be limited by these terms. These terms may be used only to distinguish one element, object, device, apparatus, component, region or section, etc., from another element, object, device, apparatus, component, region or section, etc., and do not necessarily imply a sequence or order unless clearly indicated by the context. 
     Moreover, it will be understood that various directions such as “upper”, “lower”, “bottom”, “top”, “left”, “right”, “first”, “second” and so forth are made only with respect to explanation in conjunction with the drawings, and that components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the concept(s) herein taught, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as illustrative and non-limiting. 
     The apparatuses/systems and methods described herein can be implemented at least in part by one or more computer program products comprising one or more non-transitory, tangible, computer-readable mediums storing computer programs with instructions that may be performed by one or more processors. The computer programs may include processor executable instructions and/or instructions that may be translated or otherwise interpreted by a processor such that the processor may perform the instructions. The computer programs can also include stored data. Non-limiting examples of the non-transitory, tangible, computer readable medium are nonvolatile memory, magnetic storage, and optical storage. 
     As used herein, the term module can refer to, be part of, or include an application specific integrated circuit (ASIC); an electronic circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor (shared, dedicated, or group) that performs instructions included in code, including for example, execution of executable code instructions and/or interpretation/translation of uncompiled code; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip. The term module can include memory (shared, dedicated, or group) that stores code executed by the processor. 
     The term code, as used herein, can include software, firmware, and/or microcode, and can refer to one or more programs, routines, functions, classes, and/or objects. The term shared, as used herein, means that some or all code from multiple modules can be executed using a single (shared) processor. In addition, some or all code from multiple modules can be stored by a single (shared) memory. The term group, as used above, means that some or all code from a single module can be executed using a group of processors. In addition, some or all code from a single module can be stored using a group of memories. 
     As used herein, a test plot will be understood to mean a single field, or one of a plurality plots within a research field that has been subdivided into a plurality of plots. Each test plot typically comprises one or more rows of plants comprising from about 5 to about 15 or 20 plants in each row, wherein the plants are subject to various crop breeding and analytics research procedures and tests for developing various strains, hybrids, genotypes, etc. of plants. For example, test plots in a growing area can receive certain treatments (e.g. chemical applications to the plants and/or growing environment), and/or can comprise plants of certain genetics, and/or combinations thereof. Each test plot within a field is purposely separated from other test plots by a gap, or alleys, where no plants are grown. The gaps or alleys maintain the identity of the plant material within each respective test plot. Hence, there are typically many alleys in a research field, often comprising 10-30 feet of space with no plants. 
     As used herein, a microbe will be understood to be a microorganism, i.e. a microscopic living organism, which can be single celled or multicellular. Microorganisms are very diverse and include all the bacteria, archea, protozoa, fungi, and algae, especially cells of plant pathogens and/or plant symbiots. Certain animals are also considered microbes, e.g. rotifers. In various embodiments, a microbe can be any of several different microscopic stages of a plant or animal. Microbes also include viruses, viroids, and prions, especially those which are pathogens or symbiots to crop plants. 
     As used herein the term plant refers to a whole plant, any part thereof, or a cell or tissue culture derived from a plant, comprising any of: whole plants, plant components or organs (e.g., leaves, stems, roots, etc.,), plant tissues, seeds, plant cells, and/or progeny of the same. A plant cell is a biological cell of a plant, taken from a plant or derived through culture from a cell taken from a plant. 
     As used herein the term fungus refers to a whole fungus, any part thereof, or a cell or tissue culture derived from a fungus, comprising any of whole fungus, fungus components or organs, fungal tissues, spores, fungal cells, including cells of hyphae and/or cells of mycelium, and/or progeny of the same. A fungus cell is a biological cell of a fungus, taken from a fungus or derived through culture from a cell taken from a fungus. 
     As used herein the phrase population of plants or plant population means a set comprising any number, including one, of individuals, objects, or data from which samples are taken for evaluation, e.g. estimating QTL effects and/or disease tolerance. Most commonly, the terms relate to a breeding population of plants from which members are selected and crossed to produce progeny in a breeding program. A population of plants can include the progeny of a single breeding cross or a plurality of breeding crosses, and can be either actual plants or plant derived material, or in silico representations of the plants. The population members need not be identical to the population members selected for use in subsequent cycles of analyses or those ultimately selected to obtain final progeny plants. Often, a plant population is derived from a single biparental cross, but can also derive from two or more crosses between the same or different parents. Although a population of plants can comprise any number of individuals, those of skill in the art will recognize that plant breeders commonly use population sizes ranging from one or two hundred individuals to several thousand, and that the highest performing 5-20% of a population is what is commonly selected to be used in subsequent crosses in order to improve the performance of subsequent generations of the population. 
     Referring now to  FIG. 1 , the present disclosure generally provides systems and methods for post-harvest determination of pre-harvest strength of a corn stalk. That is, the present disclosure generally provides systems and methods for determining the strength of corn stalks at a desired growth stage, e.g., growth stage R4, R5, R6, black layer, etc., after the corn stalks have been severed and the corn plants have been harvested. Implementation of the systems and methods of the present disclosure allow the corn plants to grow to maturity, or until harvested, without being damaged because the stalk strength analysis and determination is performed on the discarded stalk stumps that remain rooted in the ground in the field after harvest of the corn plants. 
     As used herein, it should be understood that post-harvest stalk stumps refer to the discarded stalk stumps that remain rooted in the ground in the field after harvest of the corn plants, and that the method and systems described herein are utilized and implemented on such discarded stalk stumps that remain rooted in the ground in the field after harvest of the corn plants. 
     In various embodiments, the present disclosure provides a post-harvest stalk strength determination system  10  for determining stalk strength at any desired growth stage prior to harvest that generally comprises at least one stalk stump cutter  14 , at least one imaging device  18  and at least one computer based data processing system  22 . Although the system  10  can include a plurality of stalk stump cutters  14  and/or a plurality of imaging devices  18  and/or a plurality of data processing systems  22 , for simplicity and conciseness the system  10  will be described herein as comprising a single stalk stump cutter  14 , a single imaging device  18 , and a single data processing system  22 . In various embodiments, the stalk stump cutter  14  can be structured and operable to cut, at any desired angle, a discarded post-harvest stalk stump  26  to provide a substantially flat and even cross-sectional surface  30  (often referred to herein simply as the cross-section  30 ) of the stalk stump  26 . The stalk stump cutter  14  can be any device operable to cut or sever discarded post-harvest stalk stumps  26  such that a substantially flat even cross-section  30  is provided. For example, in various instances the stalk stump cutter  14  can comprise a discus saw blade (similar to a hand-held power saw blade) and a motor that spins the discus saw blade to cut the post-harvest stalk stumps  26  to provide the prepared cross-sections  30 . In other instances, the stalk stump cutter  14  can comprise an automated scissor device that slices through the post-harvest stalk stumps  26  to provide the prepared cross-sections  30 . Alternatively, the stalk stump cutter  14  can comprise one or more spinning knife blade (similar to a lawn mower blade) and a motor that spins the knife blade to sever the post-harvest stalk stumps  26  to provide the prepared cross-sections  30 . 
     It is envisioned that in various embodiments, the stalk stump cutter  14  can comprise a combine chopping head that is structured and operable to cut the corn plants such that the discarded stalk stump that remains has a substantially flat even cross-section. 
     In various instances, the imaging device  18  is structured and operable to acquire image data of the stalk stump cross-section, and the computer based data processing system  22  is structured and operable to analyze the image data and determine a pre-harvest (e.g., prior to harvest) or at harvest (e.g., during harvest) stalk strength of the corresponding plant stalk. The imaging device  18  can be any imagining device or sensor suitable to gather desired image data of each prepared stalk stump cross-section  30 , such as charged coupled device (CCD) camera, an infrared (IR) camera, a high resolution digital camera, or any other suitable imaging device. 
     As used herein a post-harvest corn stalk stump  26  will be understood to mean the portion of a corn stalk extending from the ground after the stalk has been cut by a harvesting machine, e.g., a corn harvester, to harvest the corn of the respective stalk. More specifically, as used herein a post-harvest corn stalk stump  26  is the discarded stalk stump and left behind in the field as refuse to be tilled into the soil the next planting season. Discarded post-harvest stalk stumps  26  that have been cut by the stalk stump cutter  14  and have substantially flat and even cross-sections  30  will be referred to herein as being ‘prepared’ stalk stumps  26 . 
     The data processing system  22  can be any computer or processor based system or device suitable for electronically communicating (wired or wirelessly) with the stalk stump cutter  14  and/or the imaging device  14  to receive image data from the imaging device  18 , and/or control the operation of the imaging device  18 , and/or receive operational data from the stalk stump cutter  14 , and/or control operation of the stalk stump cutter  14 , and process and analyze the image data to determine a pre-harvest stalk strength of the respective corn stalk. Particularly, in various instances, the data processing system  22  is structured and operable to process and analyze the image data to determine the stalk strength of the respective stalk at a desired growth stage of the respective corn plant, e.g., growth stage R4, R5, R6, black layer, etc. It is envisioned that the computer based data processing system  22  can comprise any combination of a general-purpose computer, any other computer based system or device, and one or more application specific integrated circuits (ASICs), electronic circuits, combinational logic circuits, field programmable gate arrays (FPGA), or other hardware components that provide various functionality of the system  10 , as described herein. Furthermore, the data processing system  22  can be a single component or multiple components that are located locally on/at the system  10  or remotely from the system  10 , or a combination thereof. 
     Furthermore, in various embodiments, one or more of the components of the system  10 , e.g., the stalk stump cutter  14 , the imaging device  18 , the data processing system, and all other components of the system  10  described herein can be standalone units such that they are not interconnected or mounted to a common structure, and can be utilized independently in separate sequential phases. For example, in various instances the stalk stump cutter  14 , the imaging device  18  and the data processing system  22  can each be an independent standalone unit wherein the stalk stump cutter  14  is carried, pushed, pulled, or driven through a plot and used to prepare (e.g., cut) a plurality of or all of the stalk stumps  26  in the plot such that a plurality or all the respective stalk stumps  26  have a substantially flat and even cross-section  30 , as a first step or process. It should be understood that the stalk stump cutter  14  can cut the respective stalk at any angle (e.g., 90°, 45°, 30°, etc.) relative to the length of the plant stalk (e.g., a longitudinal axis of the plant stalk) such that a substantially flat and even cross-sectional surface  30  is provided. In various instances, the stalk stumps  26  are cut (e.g., prepared) between the second and third internodes. Subsequently, in various instances, the stalk stump cutter  14  is set aside and the imaging device  18  can be carried, pushed, pulled, or driven through the plot and used to capture image date of each respective stalk stump flat and even cross-section  30 , and communicate the captured image data to the data processing system  10 , as a second step or process. Thereafter, the imaging device  18  is set aside and the data processing system  22 , located remotely or separately from the stalk stump cutter  14  and the imaging device  18  processes and analyzes, via execution of one or more stalk strength algorithms, the captured image data for each stalk stump cross-section  30  and determines a stalk strength value for each stalk stump  26  at a desired pre-harvest growth stage of the respective corn plants. For example, in various embodiments the image data can be assayed to determine the color of the tissue in a pith region of the stalk stump cross-section  30  (as exemplarily illustrated in  FIG. 6 ). 
     It is envisioned that in various embodiments, the system and method do not include the imaging device  18  or the data processing system  22 . In such instances, once the discarded stalk stumps  26  have been prepared by the stalk stump cutter  14 , which in various embodiments can be a chopping head within the harvesting head(s)  62  of a corn harvester or corn harvesting combine, manual visual data can be collected and recorded (recorded manually or electronically) by one or more data collecting person in the field, and subsequently analyzed by one or more data analysis person. 
     In various other instances, one or more of the components of the system  10 , e.g., the stalk stump cutter  14 , the imaging device  18 , the data processing system, and all other components of the system  10  described herein, can be mounted to a common structure or chassis such as a mobile platform  34  exemplarily illustrated in  FIGS. 3, 4, 5 and 7 . In such instances, the stalk stump cutter  14  can be mounted forward of the imaging device  18  on the mobile platform  34  (e.g., the common structure or chassis) and the mobile platform  34  can be pushed, pulled, or driven through the plot such that, as the mobile platform  34  traverses a row of discarded stalk stumps, the stalk stump cutter  14  prepares (e.g., cuts) each discarded stalk stump  26  and thereafter the imaging device  18  collects the image data of the respective stalk stump cross-sections  30 . In such instances, the stalk stump cutter  14  can be positioned on the mobile platform  34  a distance from the imaging device  18  such that one or more (e.g., 1, 2, 3 or 4) discarded stalk stumps  26  are prepared (e.g., cut) by the stalk stump cutter  14  before the imaging device  18  passes over the prepared discarded stalk stumps  26  to collect the image data of the respective cross-sections  30 . For example, the stalk stump cutter  14  can be positioned on the mobile platform  34  a distance from the imaging device  18  such that a first and a second stalk stump  26  will be prepared (e.g., cut) and the first stalk stump cross-section  30  will not be imaged by the imaging device  18  until after the second stalk stump  26  is prepared (e.g., cut). In various instances, the stalk stumps  26  are cut (e.g., prepared) between the second and third internodes. 
     Again, it is envisioned that in various embodiments, the stalk stump cutter  14  can be a chopping head within one or more corn harvesting head(s)  62  that cut(s) mature corn plants to harvest the corn plants leaving behind discarded stalk stump  26  that have been prepared by the harvesting combine harvesting head(s)  62  to have substantially flat and even cross-sectional surface  30 . 
     Referring now to  FIG. 2 , in various embodiments, the system  10  can further include a debris dispersion device  38  that is structured and operable to disperse or remove any debris from around each cut stalk stump  26  prior to imaging of the prepared stalk stumps  26 . The debris can include such things as twigs, leaves, splinters, chunks, pieces, or remnants of the corn plants and/or stalks that result from harvesting of the corn plants and/or preparing (e.g., cutting) of the stalk stumps  26  by the stalk stump cutter  14 . By dispersing or removing of the debris from around the stalk stumps  26  prior to imaging thereof, the image data of each stalk stump cross-section  30  collected manually/visual or by the imaging device  18  will not include and be substantially free of data representative of any such debris surrounding the respective stalk stump  26 , e.g., the image data will not be cluttered with data representative of any such debris, thereby making analysis of the acquired image data manually or by the data processing system  22  easier and more accurate. Accordingly, prior to manually viewing or passing the imaging device  18  over the tops of the prepared stalk stumps  26  to collect image data of the cross-sections  30 , the debris dispersion device  38  will clear the ground surrounding the base of respective stalk stump(s)  26  of debris (e.g., disperse or remove the debris from the ground surrounding the base of the respective stalk stumps  26 ) so that clean, clear, uncluttered image data of the respective cross-sections  30  can be obtained. The debris dispersion device  38  can be any device structure and operable to disperse or remove debris on the ground around the stalk stumps  26  such as a broom, brush, rack, vacuum device or blower device. In various embodiments, as exemplarily shown in 3, 4 and 5 the debris dispersion device  38  can be a blower device operable to generate a stream of air that can be directed toward the ground at the base of stalk stumps  26  to disperse or blow away debris surrounding the base of the stalk stumps  26 . 
     As described above, in various embodiments one or more of the components of the system  10  can be standalone units such that they are not interconnected or mounted to a common structure, and can be utilized independently in separate sequential phases or operations. In such embodiments, wherein the system  10  includes the debris dispersion device  38 , after the stalk stumps  26  have been prepared using the stalk stump cutter  14  in a first step or process, the debris dispersion device  38  can be carried, pushed, pulled, or driven through a plot and used to disperse or remove the debris from around at least the base of each stalk stump  26 , as a second step or process. Thereafter, in various instances, the imaging device  18  can be carried, pushed, pulled, or driven through the plot and used to capture image date of each respective stalk stump flat and even cross-section  30  and communicate the captured image data to the data processing system  10 , as a third step or process. As also described above, in various instances, the data processing system  22 , located remotely or separately from the stalk stump cutter  14 , debris dispersion device  38  and the imaging device  18 , processes and analyzes, via execution of one or more stalk strength algorithms by one or more processor of the data processing system  22 , the captured image data for each stalk stump cross-section  30  and determines a stalk strength value for each stalk stump  26  at a desired pre-harvest growth stage of the respective corn plants (e.g., R4, R5, R6 or black layer). 
     As also described above, in various embodiments, one or more of the components of the system  10  can be mounted to a common structure or chassis such as a mobile platform  34  exemplarily illustrated in  FIGS. 3, 4, 5 and 7 . In such instances, wherein the system  10  includes the debris dispersion device  38 , the stalk stump cutter  14  can me mounted forward of the imaging device  18  on the mobile platform  34  and the debris dispersion device  38  can be mounted between the stalk stump cutter  14  and the imagining device  18 . In operation, the mobile platform  34  can be pushed, pulled, or driven through the plot such that, as the mobile platform  34  traverses a row of stalk stumps  26 , the stalk stump cutter  14  prepares (e.g., cuts) each stalk stump  26 . Subsequently, in various instances, as the mobile platform continues along the row, and prior to acquisition of the image data, the debris dispersion device  38  is passed in close proximity to the base of each prepared stalk stump  26  to disperse or remove any debris around the base(s) of the respective prepared stalk stump(s)  26 . Thereafter, in various instances, as the mobile platform continues along the row, the imaging device  18  passes over each prepared stalk stump  26  that has had the debris dispersed or removed from its base and collects the image data of the respective stalk stump cross-sections  30 . In such instances, the stalk stump cutter  14  can be positioned on the mobile platform  34  a distance from the imaging device  18  such that one or more (e.g., 1, 2, 3 or 4) stalk stumps  26  are prepared (e.g., cut) by the stalk stump cutter  14 , and the debris is cleared from around the respective bases before the imaging device  18  passes over the prepared stalk stumps  26  to collect the image data of the respective cross-sections  30 . For example, the stalk stump cutter  14  can be positioned on the mobile platform  34  a distance from the imaging device  18  such that a first and a second stalk stump  26  will be prepared (e.g., cut), and the debris cleared from around their bases, and the first stalk stump cross-section  30  will not be imaged by the imaging device  18  until after the second stalk stump  26  is prepared (e.g., cut). 
     It is envisioned that the mobile platform  34  can be manually propelled, or automatically propelled, (e.g., propelled by a motor or engine) and can be a walk-behind platform (such as that shown in 3, 4 and 5) or riding platform (e.g., a tractor or a corn harvester modified to have the components of system  10  mounted thereto). It is envisioned that in various embodiments the mobile platform can be an unmanned vehicle whose movement and activities are controlled by automated systems. In the embodiments wherein the components of system  10  are mounted to a mobile platform  34 , in general operation, in various instances, after a field or plot (e.g., test plot) of corn plants have been harvested such that all that remains of the corn plants is their respective discarded post-harvest stalk stumps  26 , the mobile platform  34  having the components of the system  10  mounted thereon is traversed (e.g., manually motivated/propelled or automatically motivated/propelled) down or along a first row of stalk stumps  26 . As the mobile platform  34  travels down the row of post-harvest stalk stumps  26  are aligned with the stalk stump cutter  14  such that the stalk stump cutter  14  prepares (e.g., cuts, slices, or severs and any desired angle) the stalk stumps  26  to provide a substantially flat and even cross-section  30  for each prepared stalk stump  26 . In various instances the stalk stump cutter  14  cuts (e.g., prepares) each stalk stump  26  at substantially the same height (e.g., between the second and third internode) so that the image data acquired for each stalk stump cross-section  30  is consistent and representative of the same stalk strength data for each stalk stump  26 , thereby enhancing the accuracy of the analysis of the image data and the resulting pre-harvest stalk strength determinations. 
     After one or more of the stalk stumps  26  have been prepared by the stalk stump cutter  14 , and the mobile platform  34 /system  10  advances down the row, in various instances, the imaging device  18  is sequentially passed over each prepared stalk stump  26  and collects image data of the substantially flat and even cross-section  30  of each prepared stalk stump  26 . Simultaneously or subsequently, the imaging device  18  sends the collected image data to data processing system  22 . In such instances, the data processing system  22  executes one or more stalk strength algorithm on the collected image data for each prepared stalk stump  26  to determine a pre-harvest stalk strength for each respective stalk stump  26 . As described above, the collected image data can be utilized to determine the pre-harvest stalk strength for each stalk stump  26  at any desired growth stage of the corn plants, such as R4, R5, R6, black layer, etc. Particularly, in various embodiments, the data processing system  22  can analyze the collected image data and provide a score or an index value indicative of the desired growth stage stalk strength for each respective stalk stump  26 . More particularly, the data processing system  22  assays the image data to determine the amount of damaged or missing tissue in a pith region of the stalk stump cross-section and assigns a particular score or index number (e.g., a number between 1 and 10) that indicates the stalk strength of the respective stalk at the desired pre-harvest growth stage. That is, the data processing system  22  assigns a post-harvest score or index number to each stalk stump  26  based on the assay, wherein the score or index number corresponds to the pre-harvest stalk strength of the respective corn plant at the desired growth stage, e.g., R4, R5, R6, black layer, etc. As described above, in various embodiments, the image data can be assayed to determine the color of the tissue in a pith region of the stalk stump cross-section  30 , wherein such color data can be utilized to post-harvest determine various aspects of the pre-harvest stalk health. 
     As described above, in various embodiments, once the stalk stumps  26  have been prepared, the image data can be manually visually collected. Additionally, in such embodiments, the manually visually collected image data can be manually analyzed or entered into a data processing system (e.g., data processing system  22 ) and analyzed via execution of one or more stalk strength algorithm. 
     In the embodiments wherein the system  10  includes the debris dispersion device  38 , as the mobile platform  34 /system  10  advances down the row, subsequent to the preparation of a respective stalk stump  26  and prior to the collection of the image data thereof, the debris dispersion device  38  disperses or removes the debris from around the base of one or more of the prepared stalk stumps  26  so that the collected image data of each substantially flat and even cross-section  30  is uncluttered with background data of the debris. The process above is repeated on each row of stalk stumps  26  for which the pre-harvest stalk strength analysis is desired. 
     Referring to  FIGS. 3, 4 and 5 , in various instances of the mobile platform mounted system  10 , the system  10  can further comprise a stalk stump cutter guide  42  mounted to the mobile platform  34  and structured and operable to guide each stalk stump  26  into the blade(s) of the stalk stump cutter  14  and/or guide the blade(s) of the stalk stump cutter  14  into each stalk stump  26  such that each stalk stump  26  is prepared in a consistent manner at substantially the same height and at substantially the same angle, thereby enhancing the consistency of the acquired image data and the accuracy of the analysis thereof, and the resulting pre-harvest stalk strength determinations. 
     As exemplarily illustrated in  FIGS. 3, 4 and 5 , in various embodiments the mobile platform  34  can be motorized/self-propelled walk-behind mobile platform that comprises an engine or motor  46  that is operable and controllable to drive at least one wheel  50 . In such instances, the mobile platform  34  comprises a chassis  54  to which the motor/engine  46  is fixedly mounted and the wheels  50  are rotationally mounted. As exemplarily illustrated, the system  10  includes the debris dispersion device that comprises a blower that is mounted to the chassis  54  and driven by the motor/engine  46 . In the illustrated exemplary embodiments the stalk stump cutter  14  and the imaging device  18  are mounted to the chassis  54  via a support arm and bracket  58 . As illustrated, the stalk stump cutter  14  is disposed forward of the imaging device  18 , and the debris dispersion device  38  is disposed between the stalk stump cutter  14  and the imaging device  18 . Therefore, as the mobile platform  34 /system  10  travels down a row of post-harvest stalk stumps  26  the stalk stumps  26  are prepared, then the debris is dispersed/removed, then the image data is collected, as described above. Additionally, in the illustrated exemplary embodiments, the system  10  includes the stalk stump cutter guide  42  that is mounted to support arm and bracket  58 . 
     Referring now to  FIG. 7 , it is envisioned that in various embodiments, the mobile platform  34  can be a motorized/self-propelled riding vehicle such as a tractor or a corn harvester. For example, as exemplarily illustrated in  FIG. 7 , in various embodiments the mobile platform  34  can be a corn harvester that is structured and operable to harvest corn from corn plants in a field leaving behind the discarded post-harvest (e.g., unprepared, or pre-preparation) stalk stumps  26 . In such embodiments, the stalk stump cutter  14  and the imaging device  18 , and, in various instances, the debris dispersion device  38  can be mounted under the harvester. Accordingly, as the harvester is driven through a field of corn, the harvester will harvest the corn as is known in the art, leaving the discarded post-harvest/pre-preparation stalk stumps  26 , Thereafter, as the harvester continues to travel though the field, the stalk stump cutter  14  will prepare the stalk stumps  26  to provide the substantially flat and even cross-sectional surfaces  30 , the debris dispersion device  38  (if included) will disperse or remove the debris from around the base of freshly harvested and prepared stalk stumps  26 , and the imaging device  18  will acquire the image data of the cross-sections  30  and communicate the image data to the data processing system  22 . Thereafter, the image data is analyzed as described above. Hence, in such embodiments, the corn can be harvested and the stalk stumps  26  analyzed concurrently. 
     In such embodiments, the harvester typically will simultaneously harvest a plurality of rows of corn as the harvester traverses the field. Therefore, in such embodiments, and other envisioned embodiments, the system  10  can comprise a plurality of data collection subsystems, wherein each subsystem comprises a respective stalk stump cutter  14  and a respective imaging device  18 , and in various instances a respective debris dispersion device  38 . Specifically, the system  10  would comprise a number of data collection subsystems equal to the number of harvesting heads  62  the harvester includes. Each subsystem would have the respective components (e.g., the stalk stump cutter  14 , the debris dispersion device  38  and the imaging device  18 ) linearly aligned with a respective one of the harvesting heads  62  such that as the harvester traverses the field harvesting the corn, thereby generating a plurality of rows of post-harvest/pre-preparation stalk stumps  26 , each respective row of stalk stumps  26  can be prepared and the image data collected by the respective data collection subsystem concurrently with the harvesting. 
     As described above, in various embodiments, the corn harvester head(s)  62  can comprise the stalk stump cutter(s)  14 . 
     In various embodiments wherein the mobile platform  34  is a motorized/self-propelled riding vehicle, in order to enhance the accuracy and consistency of the image data collected, the system  10  can further include a skirt or shroud  64  disposed around the bottom of the respective vehicle and suspended downward toward the ground (e.g., disposed around the bottom of a harvester and suspended toward the ground). The skirt/shroud  64  is disposed around a bottom of the corn harvesting machine to substantially enclose and shield an area beneath the mobile platform (e.g., the corn harvester) in which the imagining device(s)  18  is/are mounted from ambient light. More specifically, in various instances, the skirt/shroud  64  will be such that it will hang from the bottom of the mobile platform  34  such that the bottom of the skirt/shroud  64  will touch or nearly touch the ground. The skirt/shroud  64  is structured and operable to block a significant portion (e.g., 100% to 75%) of the ambient light from radiating or shining beneath the mobile platform  34 . In such instances, the system  10  can further include one or more lights  66  or other light source (e.g., infrared (IR) lighting source(s)) disposed under the mobile platform  34  that are structured and operable to provide light or other illumination on at least the area around each prepared stalk stump  26  as the imaging device(s)  18  is/are collecting the image data. Particularly, the lighting source(s)  66  will provided a consistent light or other illumination (e.g., IR illumination) intensity for all image data collected, thereby improve the analysis and consistency of the image data collected and the resulting pre-harvest stalk strength determinations. Moreover, the skirt/shroud  64  shields the imaging device(s) field of view from chaff, plant debris, ambient light and/or other “noise” that may affect data collection and/or analysis. A controlled sensing environment like this would permit reliable and repeatable imaging/data collection to occur at substantially at any hour of the day and/or in any lighting conditions. 
     With further reference to  FIG. 7 , in various embodiments, the system  10  can comprise a global positioning system (GPS)  70  that is structured and operable to acquire location data of each stalk stump  26  as each stalk stump  26  is prepared, imaged and analyzed, and communicate such location data to the data processing system  22 . Accordingly, comprehensive analysis of an entire field can provide corresponding location data with the respective stalk strength data for each stalk stump  26  in the field, which can be overlay with a field map that details various phenotype and genotype characteristics of each pre-harvest corn plant in the field. Although the GPS  70  is exemplarily shown in  FIG. 7  in correlation with the harvester embodiments described above, it should be understood that the GPS  70  can be also included in the wall-behind embodiments described above. 
     Furthermore, it is envisioned that in various embodiments, the post-harvest stalk strength determination system  10  described above can be fully-automated, capable of using electronic geo-location (e.g., GPS data) to perform all of the activities necessary to assess the stalk strength of thousands or more plants per hour, thereby providing plant breeders with accurate and high-throughput system(s) and method(s) of estimating the pre-harvest stalk strength of thousands or more plants per hour. For example, the stalk strength analysis described above can be performed post-harvest to determine the stalk strength of the respective corn plants during the pre-harvest grain fill period, for a plurality of corn plants without damaging the plants. The stalk strength data obtained by the system(s) and method(s) described herein can be combined with other types of data collected about the plants&#39; performance (e.g. yield, disease resistance) to provide plant breeders a highly-accurate, high-throughput method of assessing overall crop performance. 
     Referring now to  FIG. 8 , as described above, in various embodiments, wherein the mobile platform  34  can be a motorized/self-propelled riding vehicle such as a tractor or a corn harvester, the corn harvester head(s)  62  can comprise the stalk stump cutter(s)  14 . In various instances of such embodiments, the imagine device(s)  18  and/or other desired imaging sensors can be disposed in a pull-behind imaging subsystem  74  that connected to the back end of the harvester  34  and pulled behind the harvester as the harvester  34  traverses the field. In such instances, as the harvester  34  traverses the field, it pulls the imaging subsystem  74  relative to the stalk stumps  26  so that the imaging devices  18  can collect images and/or other data related to the stalk pith of each stalk stump  26  as each stalk stump  26  passes through a field of view  78  of respective imagining device(s)  18 . In various embodiments, the imaging subsystem  74  can include enclosure structure  82  having inner surfaces to which the imaging device(s)  18  is/are mounted. In various instances, the enclosure structure  82  can be opaque such that ambient light cannot pass therethrough. 
     In various embodiments, in order to enhance the accuracy and consistency of the image data collected, the imaging subsystem  74  can include a skirt or shroud  86  disposed around the bottom of the enclosure structure  82  and suspended downward toward the ground. The skirt/shroud  82  is disposed around a bottom of the enclosure structure  82  to substantially enclose and shield an area beneath the enclosure structure  82  in which the imagining device(s)  18  is/are mounted from ambient light. More specifically, in various instances, the skirt/shroud  86  will be disposed such that it will hang from the bottom of the enclosure structure  82  so that the bottom of the skirt/shroud  86  will touch or nearly touch the ground. The skirt/shroud  86  is structured and operable to block a significant portion (e.g., 75% to 100%) of the ambient light from radiating or shining beneath the enclosure  82  of the imaging subsystem  74 . In such instances, the imaging subsystem  74  can comprise one or more lighting or illumination source  90  (e.g., an infrared (IR) illumination source) mounted to the enclosure inner surface that are structured and operable to provide light or other illumination (e.g., IR illumination) within the interior of the enclosure  82 . Particularly, the lighting source(s)  90  will provided a consistent light or other illumination (e.g., IR illumination) intensity for all image data collected, thereby improve the analysis and consistency of the image data collected and the resulting pre-harvest stalk strength determinations. Moreover, the skirt/shroud  78  shields the imaging device(s) field of view  78  from chaff, plant debris, ambient light and/or other “noise” that may affect data collection and/or analysis. A controlled sensing environment like this will permit reliable and repeatable imaging/data collection to occur at substantially at any hour of the day and/or in any lighting conditions. 
     Although the stalk stump cutter(s)  14 , the debris dispersion device(s)  38  and the imaging device(s)  18  have been described above with regard to various exemplary embodiments and locations thereof, it should be understood that; 1) the stalk stump cutting/preparation can be done using any suitable stalk stump cutter  14  that can hand carried and operated, or located anywhere on any suitable mobile platform  34  or subsystem; 2) the debris from around each cut stalk stump  26  can be dispersed or removed using any debris dispersion device  38  that can hand carried and operated, or located anywhere on any suitable mobile platform  34  or subsystem such that the debris is dispersed after the stalk stumps  26  are prepared by the respective stalk stump cutter  14  and prior to image collection by the respective imagining device(s)  18 ; and 3) the imaging and data collection of the prepared stalk stump cross-sections  30  of stalk stumps  26  can be collected at any time after the stalk stumps  26  have been cut using any imagine device(s)  18  that can hand carried and operated, or located anywhere on any suitable mobile platform  34  or subsystem such that the image data can be collected at any time after the stalk stumps  26  are prepared by the respective stalk stump cutter  14 . 
     Referring now to  FIGS. 1 through 8B , it is envisioned that imaging device(s)  18 , as described in any of the embodiments described herein, can comprise substantially any type of imaging device, sensor, (hyperspectral) camera, etc., that is useful for collecting image data or other energy values (e.g. digital images, IR images, intensities of electromagnetic energy at certain wavelengths, etc.) could be deployed within the system  10  to collect the data, depending on the user&#39;s objective. In various embodiments, the image data could be geospatially tagged as the post-harvest stalk strength determination system  10  is moved through the field, providing researchers with precise locations of each stalk stump  26  in a field and its respective stalk health score, based on analyzing the stalk pith using methods described herein. 
     Although the various embodiments of the mobile platform  34  have been exemplarily described herein as ground-contact vehicles, other forms of the mobile platform  34  are envisioned, such as (unmanned) aerial vehicles. Moreover, any means of moving the post-harvest stalk strength determination system  10  relative to the stalk stumps  26  could be used in conjunction with the methods disclosed herein. 
     Referring now to  FIG. 9 ,  FIG. 9  exemplarily illustrates several examples of how the post-harvest stalk strength determination system  10 , such as that exemplarily illustrated in and described with regard to in  FIGS. 8A and 8B  can be used, in various instances, to harvest corn and/or collect stalk health data/images in a research field related to stalk health. In the part  1  of  FIG. 9 , stover and other lose plant debris is deposited alongside the mobile platform/combine  34  adjacent or in rows 1 and 4 (Plot A Row 1 and Plot B Row 4), while imaging can be conducted on header rows 2 and 3 (Plot A Row 2 and Blot B Row 3). Other combinations and/or permutations are envisioned. Part  2  of  FIG. 9  exemplarily illustrates how a field of plants divided into separated (research) plots can be prepared and analyzed for stalk health during harvest. When the mobile platform/combine  34  turns at the end of the field and begins to work its way back, stover and/or plant debris from the current path of the harvester can be deposited such that it overlaps the stover/plant debris that was deposited from a previous path of the harvester. 
     Part  3  of  FIG. 9  exemplarily illustrates how 4-row research plots can be prepared and analyzed for stalk health analysis contemporaneously with harvest. Other combinations and permutations of these examples are envisioned. 
     It should be understood that although the removal or dispersion of debris from around each cut stalk stump  26  has been described above utilizing the debris dispersion devices  38  exemplarily described above, it is envisioned that, in various embodiments, the post-harvest stalk strength determination system  10  can include any device, system, subsystem, mechanism or apparatus suitably structured and operable to remove or disperse from area surrounding the prepared stalk stump cross-sections  30  of stalk stumps  26  prior to the respective stalk stump cross-sections  30  being imaged via the imaging device(s)  18 . For example, in various instances wherein the mobile platform  34  is a combine, the discharge (e.g., the severed portions of the stalks) can be funneled back into the combine and then deposited at a later time (e.g., out the rear of the combine) after the respective imaging data has been collected. Or, in other instances, the discharge can be deposited or funneled to a separate vehicle (e.g. truck, etc.) and used as stover. 
     EXPERIMENTAL EXAMPLES 
     The following are experimental examples of use of the post-harvest stalk strength determination system  10  as described above. 
     Experimental Example 1. Referring to  FIGS. 10 and 11 , in 2016, carbohydrate stress resulting from reduced levels of photosynthesis was induced in two sets of complementary trials. Sixty corn hybrids, i.e., 20 hybrids each from 100, 105 and 110 relative maturity (RM) groups, were planted in both sets of trials. Fifty-eight hybrids were common among the two sets of trials. 
     In one set of trials, leaves from the bottom half of plants (i.e., all leaves below the primary ear node) were physically removed between the R1 and R2 growth stages by stripping leaves from plants. Hybrids were replicated twice in a split-plot randomized complete block design with two replicates. The three RM groups were assigned to main plots and 20 hybrids per RM group were planted in two-row plots with about 40 plants per plot per hybrid in each sub-plot. Hence, mean incidence (%) of plants failing the push test and incidence (%) of plants with healthy stalks were calculated from a sample of about 80 plants per hybrid. These trials were repeated at two locations, Waterman, Ill. and Evansville, Ind. 
     In the second set of trials, different levels of nitrogen fertilizer (N) and different plant population densities (D) were used to create different levels of photosynthetic and carbohydrate stresses. The four N×D treatments ranked from hypothesized least stress to most stress, included: 
     36K plants per acre with 240 lb N applied 
     42K plants per acre with 240 lb N applied 
     47K plants per acre with 180 lb N applied 
     42K plants per acre with 60 lb N applied 
     Treatments were replicated twice in a split-split plot of a randomized complete block design. N+D treatments were applied to main plots; RM groups were assigned to sub-plots; and four-row plots of hybrids were planted in sub-sub-plots with approximately 40 plants per row. Incidence (%) of plants with healthy stalks were sampled from a single, middle row of four-row plots. Hybrid mean incidence (%) of plants with healthy stalks were calculated from a sample of approximately 320 plants per hybrid (40 plants per plot×2 replicates×4 N+D treatments). These trials were repeated at four locations, Mineral, Ill., and Alburnett, Independence, and Green Mountain, Iowa. 
     Stalk strength of plants was tested with the “push test”, a standard practice employed by corn growers for nearly 80 years to determine if a plant is likely to lodge. Within one to two weeks of harvest, individual plants are pushed at about waist height to 45 degrees of upright and released. Plants that return to close to an upright position “pass” the push test and are considered to have adequate stalk strength to prevent lodging prior to harvest. Plants with stalks that break or those that do not return to a nearly upright position “fail” the push test and are considered to be likely to lodge if strong winds or storms occur in the field prior to harvest. 
     In all trials, incidence of plants with healthy stalks was assessed by the method described herein using the post-harvest stalk strength determination system  10  described herein. Particularly, following harvest of corn grain, using the stalk stump cutter  14  (as described above), a clean cut was made across the corn stumps  26  that remained standing after combining, thus producing a cross section of the stalk stumps  26  at about the second internode above the soil line. Pith tissues were examined from each the cross section and placed into one of two categories: healthy—50% or more of the pith tissue intact; or unhealthy—less than 50% of the pith tissue intact. Stalks stumps with less than 50% of pith tissue intact frequently were discolored and rotted as the result of fungal colonization. Incidence (%) of plants passing the push test and incidence (%) of plants with healthy stalks were measured (using the system  10  described herein) from the same plots (plants) in the trials at Waterman, Ill. and Evansville, Ind. The association between the push test and the stalks determined to be healthy using the system  10  was examined from scatterplots and correlations of the means of the 60 hybrids in each trial ( FIG. 10 ). Similarly, the association between incidence of plants passing the push test in the Waterman and Evansville trials and incidence of plants with determined (via system  10 ) to have healthy stalks in the four N+D trials was examined from scatterplots and correlations of means of the 58 hybrids common to the two sets of trials ( FIG. 11 ). 
     Experimental Example 2. Referring now to  FIG. 12 , during the corn growing season of 2017, another set of experiments were conducted to test the efficacy of determining stalk strength by examining post-harvest discard utilizing the post-harvest stalk strength determination system  10  described herein. The experiments were similar to the 2016 carbohydrate stress trials described herein. Experiments comprised 4 repetitions of plots planted with a 110 RM hybrid at four different locations in the USA (Huxley, Iowa; Jerseyville, Ill.; Waterman, Ill.; Fort Branch, Ind.). At each location, two of the repetitions served as the experimental group and were subjected to carbohydrate stress by leaf stripping, as described in Example 1, the other two repetitions served as controls (not stripped). Each repetition comprised 72 plants planted in two 11 ft rows, 18 plants/row. 
     At harvest time, all plants were subjected to the push test as described in Example 1, and the color of each stalk noted as either green or brown. Following combine harvest, the usually-discarded stalk stumps were prepared using system  10  as described above, and analyzed as described in Example 1. The mean incidence (%) of plants failing the push test and incidence (%) of plants with healthy stalks were calculated for each repetition.  FIG. 12  reveals the association between the push test and healthy stalks for the Waterman trials; the results from analyzing the data and results generated from the other sites were similar. Note that the slope in this figure is positive because the Y-axis=% passed, instead of % failed (which is the opposite of  FIG. 10 ). 
     Experimental Example 3. In 2018, two sets of tests were conducted; a first set in which stalk stress was induced by N restriction and increased D in a first set of corn plants of the 100, 105, and 110 RMs (relative maturity groups), and a second set in which stalk stress was induced only by increased D on a second set of corn plants from the 95, 115, and 120 RMs. The stalk stress was induced to create populations with diverse stalk health to test the methods disclosed herein and demonstrate that they can be used with a diverse range of accompanying technologies, including automated vehicles and computer algorithms. 
     In the N+D trials, a first group was planted at higher planting density (44 k plants/acre) and a second group was planted at a lower planting density (38 k plants/acre). The higher-density population received a 60 lbs/acre treatment of N just prior to planting, and then a side dress of additional 60 lbs/acre of N later as a side dress. The lower-density population was provided with only the pre-plant N 60 lbs/acre treatment. Four replications per RM were conducted, with two replicates per N treatment, resulting in about 84-96 hybrids tested, depending on the RM. These replications were repeated at five United States locations (Tripoli, Iowa; De Soto, Iowa; Shabbona, Ill.; Oskaloosa, Iowa; and Raritan, Ill.). 
     In the D only trials, plants were grown at one of two densities (42 k plants/acre or 48 k plants/acre) at three different US locations; four replications per planting location per density for a total of 8 reps for each of the three RMs at each location. 
     In each set of trials, following combine harvest, the stalk stumps discarded were prepared using system  10  as described above, and scored manually as either healthy or unhealthy, as described in Example 1. Then, a camera onboard an unmanned aerial vehicle (UAV) was flown over the plots to collect overhead images of the stalk stumps and the exposed pith region of the plants. The images were then analyzed by an algorithm designed to distinguish stalks and score the integrity of the pith tissue, analogously to how manual scoring is performed by a human on foot. 
     Results were encouraging, as both methods were able to reliably differentiate most stalks and assign them into health vs. unhealthy categories. Figure A 5  shows examples of images collected by the UAV and scored by the algorithm, including examples of RGB thresholds the algorithm used to make its calls. 
     Experimental Example 4. Tests were conducted of the system  10  and automated methods of preparing post-harvest discard (corn stalk stumps) for stalk health analysis, as described herein. Reliable cross-sections with sufficiently clean and uniform surfaces that the automated image analysis and/or manual scoring methods described herein could be used to score stalk pith health was achieved by using a commercially-available combine modifies with one or more stalk stump cutter(s)  14  (as described above), and/or an auto-head height control, and/or a row guidance system, and/or a cornrower device to help move debris and stover away from the stalk stumps. This system was successfully used to prepare stalk stumps for scoring during the 2018 Trials described in Example 3. 
     As used herein, stalk health refers broadly to the health of the cells and/or tissues comprising the plant stalk and are not limited to scoring plants for specific types of diseases or stalk performance. For example, the methods disclosed herein could be used to score plants for tolerance and/or resistance to infection by substantially any pathogen, especially those known to infect plant stalks, or affect the heath of the stalk and/or its performance, be they fungal, bacterial, viruses or any other type of infection. These methods could also be used to rate plants for other causes or symptoms of weakened stalk, for example, greensnap and/or other genetically-related stalk health issues. Stalk health also includes consequences to, or responses by, the plant to exposure to chemicals and/or exposure to anything moving through the growing area and/or interacting with the plants (e.g. any type of person, animal, machine, etc., known to be useful for the cultivation of plants). Nonlimiting examples include assessing the damage parts of a machine cause the plants as they traverse through, or over, the field and/or interact with the plants to sense information, apply treatments, collect samples, etc. For example, the efficacy and consequences of using mechanized, non-disruptive plant touch, or plant contact, sensing systems, like those described in: 1) U.S. patent application Ser. No. 15/502,548, filed Feb. 8, 2017, and titled Apparatus And Methods For In-Field Data Collection And Sampling: and/or 2) U.S. patent application Ser. No. 16/089,796, filed Sep. 28, 2018, and titled Stem Sensor: and/or 3) U.S. patent application Ser. No. 14/353,036, filed Apr. 21, 2014, and titled Plant Stand Counter; and/or 4) U.S. patent application Ser. No. 15/350,169, filed Nov. 14, 2016, and titled Plant Stand Counter, could be assessed. 
     The Applicant/assignee of the above referenced Ser. Nos. 15/502,548, 16/089,796, 14/353,036 and 15/350,169 patent applications is the same Applicant/assignee of the present application, and the above referenced Ser. Nos. 15/502,548, 16/089,796, 14/353,036 and 15/350,169 patent applications are incorporated by reference herein in their entirety such that it is envisioned that in various embodiments one or more or all the components described in one or more of the above referenced Ser. Nos. 15/502,548, 16/089,796, 14/353,036 and 15/350,169 patent applications can be combined with and/or included in the post-harvest stalk strength determination system  10  described above, and/or vice-versa. 
     The description herein is merely exemplary in nature and, thus, variations that do not depart from the gist of that which is described are intended to be within the scope of the teachings. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions can be provided by alternative embodiments without departing from the scope of the disclosure. Such variations and alternative combinations of elements and/or functions are not to be regarded as a departure from the spirit and scope of the teachings.