Abstract:
A trellis system and latch mechanism for use in growing vine plants, such as grapes, raisins and the like that is particularly suited for use with the alternate bearing method of raising such plants. The latch mechanism has a latch body that pivotally connects a support arm from one row of supports to the support arm of an adjacent row of supports. Alternatively, the latch mechanism connects a wire member on one row of supports to a wire member on an adjacent row of supports. The latch body is configured to allow the user to connect to a support arm or wire member on an adjacent row of support members on the non-bearing, renewal row to support the weight of vines and fruit that comprise the bearing row. Use of the latch mechanism allows the grower to selectively open or close the trellis system to establish the bearing or renewal rows during alternate growing seasons. Use of the latch mechanism on the renewal row allows the bearing row to be left open, which improves sunshine and air flow and results in a more productive and improved quality crop.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The field of the present invention relates generally to trellis systems for growing vine plants. More particularly, the present invention relates to a latch mechanism for selectively opening or closing trellis systems used to grow vine plants. Even more particularly, the present invention relates to such a mechanism used to support the trellis system for growing vine plants, such as grapes and raisins, by the alternate bearing method of raising such plants. 
     2. Background 
     Successful farming operations to grow crops on a commercial basis requires the application of modern horticultural practices. These horticultural practices address the specific requirements and peculiarities of each crop based on what is needed to obtain successful commercialization of the crop. For instance, most crops have certain growing characteristics that can be harmed or improved depending upon the horticultural practices applied by the grower. These characteristics determine how varying amounts of water, sunshine, fertilizer or inclement weather will affect the growth and productivity of the crop. Naturally, it is the goal of each grower to improve the productivity of his or her crops and to maximize crop production from year to year. 
     The successful commercial production of most varieties of grapes, raisins, and the like is highly influenced by the application of horticultural practices that have been developed over many years. One goal of these horticultural practices has been to reduce the random, uncontrolled growth that is natural for vine plants. Controlling the growth of vine plants such that the vines grow in a relatively restrained and uniform matter can vastly improve crop production. In particular, standard horticultural practices for large scale commercial production of vine crops generally requires vine plant growth be controlled such that the plants grow in a manner which facilitates the introduction of sun light, water and fertilizer and which permits harvesting of the crop in a method consistent with large scale farming operations. 
     Recently, many growers have begun using sophisticated trellis systems to control the growth of grape, raisin and other vine plants to improve crop production and reduce operating costs. Use of a well-designed trellis system for growing vine plants facilitates the application of irrigation water, fertilizers, insecticides and other grower-supplied materials. A properly installed trellis system will also admit more sunlight to the interior of the vines, which improves crop production and fruit coloration, and ease the harvest of the fruit from the vines. While many trellis systems used for growing vine crops have been successful at obtaining some of the benefits described above, most conventional trellis systems do not obtain all the benefits or to not fully obtain those benefits, particularly improved crop production. 
     A method of growing vine plants that has been found to be very successful at increasing crop yields is the alternate bearing method described in U.S. Pat. No. 5,711,109 by the present inventor. In summary, the alternate bearing method of growing vine crops has a plurality of vine plants placed in substantially parallel rows with a trellis structure to support and control the vine growth. The grower separates each vine plant into opposing pairs of cordons that are trained to grow along courses supported by the trellis system that are substantially aligned with the rows of plants. Canes produced from each of the four cordons are trained to extend laterally in a side-by-side relation from each cordon over the trellis system toward the center of the path between the rows of vine plants toward the canes of vines growing in the adjacent row of vine plants. Generally, the trellis systems are designed to hold the canes above the earth&#39;s surface a sufficient distance to allow workers and equipment to work in the path under the vines and fruit. Each year the path between the rows of vine plants, over which the trellis system extends and the canes are grown, are designated as either a bearing row or a renewal row. The bearing row is allowed to produce fruit from the canes while the renewal row is not (i.e, by cutting the canes), thereby having a field where every other row between the rows of plants is producing fruit. For the following year, the canes that produced fruit the previous year are cut to become the renewal row and the previous renewal row becomes the bearing row and produces fruit. Although the alternate bearing method of growing vine plants results in only one-half of each vine plant growing fruit each year, it has been found to substantially increase crop yield (i.e., typically measured in tons/acre). 
     To support the vine plants for the alternate bearing method of growing vines, growers generally utilize either a gable trellis system or a flat trellis system. Both types of trellis systems have particular benefits of producing and harvesting the vine plants. Whichever trellis system is used, it must be able to support the weight of the fruit and vines that are make up the bearing rows on the trellis system between every other row of vine plants. Without utilizing an overly massive and cost-prohibited trellis system, the trellis members in between the renewal and bearing rows must be interconnected to support the vines and fruit growing on the alternate bearing rows, thereby creating a trellis system that is closed between rows of vine plants. 
     Although the closure of the rows between the rows of vine plants is necessary to support the trellis system in the alternate bearing method of growing vine plants, it does result in some reduction in the benefits of a trellis system for vine plants. For instance, because the trellis system is closed at the center of the bearing row, it is more difficult to cut open a space between vines to allow more air and sunlight into the vine plants. It is also more difficult to utilize certain types of mechanical treating and harvesting equipment and to protect the fruit on the vines during inclement weather. 
     3. Related Art 
     A number of related art devices address trellis systems used for growing vine plants. One such patent is U.S. Pat. No. 5,711,109 (the “&#39;109 patent”) by Gary R. Pitts, the present inventor. In addition to describing the alternate bearing method of growing vines discussed above, the patent describes a trellis system that has been found to be useful for growing plants by the alternate bearing method. The trellis system of the &#39;109 patent utilizes a series of overhead trellis wires ( 36 ) that interconnect a series of main transverse cables ( 35 ) which in turn interconnect pairs of lateral upright supports ( 32 ). Although the transverse cables of the &#39;109 patent provide support for the trellis frames ( 40 ) for the alternate bearing method, it produces a closed system. Another such patent is U.S. Pat. No. 5,144,768 (the “&#39;768 patent”) to Hiyama, et al., which describes a form of an alternate bearing method that is shown in FIG. 2 as being open between the rows of plants. However, as noted at column 6, lines 32 through 44, the support portions ( 62 ) of the non crop bearing rows must be interconnected by wires to counterbalance the weight of the crop on the crop bearing rows. Although the crop bearing row is open, the non crop bearing row is not. The wires are presumably removed each year and moved from one row to the adjacent row, which would not be an easy task. 
     Each of the aforementioned patents presents an apparatus for supporting a vine plant for use with an alternate bearing method of growing such plants. However, these patents disclose and require the use of either a closed trellis system or a trellis system that requires significant amount of labor to create an open trellis for the crop bearing portion. Therefore, nothing in the prior art known to the inventor discloses an apparatus that provides the benefits of an open trellis system while being able to support the trellises for the alternate bearing method of growing crops. Consequently, a need exists for an apparatus to provide the benefits of an open trellis system that is suitable for use to support either a flat or gable trellis system when used with the alternate bearing method of growing vine plants. 
     SUMMARY OF THE INVENTION 
     The trellis system and latch mechanism of the present invention solves the problems identified above. That is to say, the present invention provides a latch mechanism that is suitable for use with flat and gable trellis systems to support vine plants grown by the alternate bearing method. The trellis system and latch mechanism of the present invention allows the various rows between the rows of vine plants to be easily and selectively opened or closed depending upon the need for access or support. 
     The latch mechanism of the present invention comprises a latch body having first end and an opposite second end. In the primary embodiment, the first end of the latch body is configured to pivotally attach to a first support arm that is attached to a first support member that is one of a plurality of support members that form a first row of support members. The second end of the latch body is configured to releasably connect to a second support arm that is attached to a second support member that is one of a plurality of support members that form a second row of support members that are adjacent to but spaced apart from the first row of support members. In an alternate embodiment, the first end of the latch body is configured to pivot around a first wire member that attaches to the support arms on the first row of support members and the second end of the latch body is configured to releasably connect to a second wire member that is attached to the support arms on the second row of support members. 
     In use, the latch mechanism effectively connects the support members in the renewal row to provide support for the vines and fruit that will significantly load the bearing row as the fruit matures. Without the latch mechanism, use of the alternate bearing method of growing vine plants requires a closed trellis system, whether flat or gabled, to support the heavy, alternate loading. Use of the latch mechanism allows the bearing rows to be left open to allow easier pruning of the vines to improve sunshine and air flow, including the use of mechanical equipment to do such cutting, and makes it easier for the grower to cover his or her vines and fruit during inclement weather. 
     Accordingly, the primary objective of the present invention is to provide an apparatus for improving the raising of vine plants. 
     It is also an important objective of the present invention to provide a trellis system for improving the large scale commercial production of crops from vine plants. 
     It is also an important objective of the present invention to provide a latch mechanism suitable for use with trellis systems utilized for the alternate bearing method of growing vine plants. 
     It is also an important objective of the present invention to provide a latch mechanism for easily and selectively opening and closing trellis systems used for growing vine plants according to the alternate bearing method. 
     Yet another important objective of the present invention is to provide a latch mechanism that pivotally connects to a support arm or wire member on one row of support members to selectively interconnect to a support arm or wire member on an adjacent row of support members. 
     The above and other objectives of the present invention will be explained in greater detail by reference to the attached figures and the description of the preferred embodiment which follows. As set forth herein, the present invention resides in the novel features of form, construction, mode of operation and combination of processes presently described and understood by the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings which illustrate the best modes presently contemplated for carrying out the present invention: 
     FIG. 1 is an illustration of the preferred embodiment of the latch mechanism of the present invention; 
     FIG. 2 is an plan view of a field of vine plants having been grown according to the alternate bearing method of raising vine plants that is using the latch mechanism of the preferred embodiment of the present invention; 
     FIG. 3 is a side view of a gable trellis system utilizing the latch mechanism of the present invention; 
     FIG. 4 is a side view of a flat trellis system utilizing the latch mechanism of the present invention; and 
     FIG. 5 is an plan view of a field of vine plants having been grown according to the alternate bearing method of raising vine plants that is using the latch mechanism of the alternate embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the figures where like elements have been given like numerical designations to facilitate the reader&#39;s understanding of the present invention, and particularly with reference to the embodiment of the present invention illustrated in FIGS. 1 through 4, the preferred embodiment of the present invention is set forth below. The latch mechanism, designated generally as  10  and shown in detail in FIG. 1, is installed in the typical trellis system  12  used to support and control vine plants  14 , such as grapes, raisins and the like, grown in a plurality of rows, as shown in FIG. 2, including first plant row  16  and second plant row  18 . Second plant row  18  is in spaced apart relation and generally parallel to first plant row  16  creating path  20  between first  16  and second  18  plant rows. A typical row spacing is  12  feet, but it is not uncommon to find spacing ranging from  6  to  14  feet. As shown best in FIGS. 3 and 4, trellis system  12  utilizes a plurality of first support members  22  that are formed in a first support row  24  substantially aligned with first plant row  16 . A plurality of second support members  26  form a second support row  28  substantially aligned with second plant row  18 . Attached to each first support member  22  is a first support arm  30  and attached to each second support member  26  is a second support arm  32 . Interconnecting the first support arms  30  on first support members  22  is a plurality of trellis wires  34 , one of which is designated as first wire member  36 . In the preferred embodiment the trellis wire furthest into path  20  from first support member  22  is first wire member  36 . Also interconnecting the second support arms  32  on each second support member  26  is a plurality of trellis wires  34 , one of which is designated as second wire member  38 . In the preferred embodiment the trellis wire furthest into path  20  from second support member  26  is second wire member  38 . 
     As illustrated in FIGS. 3 and 4, vine plants  14  have trunk  40  which is planted in ground  42  to facilitate growth of plant  14 . Plant  14  is trained by pruning to form cordons  44 . Although illustrated with four cordons  44 , it is understood in the art that plant  14  can be trained by pruning to form any desired number of cordons. The cordons  44  are trained to follow along a path parallel to first  16  and second  18  plant rows at a position spaced above ground  42  such that a pair of cordons  44  are on each side of first  22  and second  26  support members. Canes  46  are pruned and trained to extend laterally from cordons  44  over trellis wires  34  generally toward the center of path  20 . In the alternate bearing method of raising vines, one pair of cordons  44  is designated the renewal row  48  and the other is the bearing row  50 . The renewal row  48  is pruned to prevent crop growth and the bearing row  50  is pruned to facilitate crop growth. The bearing row  50  will produce fruit  52  during the normal growing season of plant  14 . The following year the two rows are reversed so that the path  20  between any two rows of plants will alternate between being a renewal row and a bearing row. 
     First  22  and second  26  support members can be made of any material suitable for use in a vineyard, such as wood, metal or various composite materials. One such material is two inch square rail steel line posts eight feet high. The height of trellis system  12  determines the height at which the bulk of fruit  52  will hang. Fruit  52  should hang at a height which is low enough for workers to reach without a stool yet high enough to allow passage of farm equipment through path  20  when fruit  52  is hanging from support arms  30  and  32 . Support members  22  and  26  are mounted in ground  42  to stand in a substantially upright position. First  30  and second  32  support arms are attached generally perpendicular to first support member  22  and second support member  26 , respectively. Trellis wires  34  help support first  22  and second  26  support members and provide a foundation for canes  46  from cordons  44 . To assist care of plants  14  and harvesting fruit  52 , one or more droppers  54  can be attached to support arms  30  and  32  to place the wire configuration at the proper elevation for the cordons  44  and first  36  and second  38  wire members. Trellis wires  34  can be made of various types of wire, including 12 gage high tensile strength galvanized wire having a tensile strength of 120,000 psi. 
     As is shown in FIG. 1, latch mechanism  10  is made from latch body  56 , which can be made from a variety of materials, such as wood, metal or various composite materials. The size of latch mechanism  10  should provide sufficient strength for latch mechanism  10  to support the weight of fruit  52  and plants  14  on bearing row  50  when it is in the closed position  58 , as discussed in more detail below. Generally, the required size of latch mechanism  10  will be dependant on the material selected for use. Latch mechanism  10  has a first end  60  and second end  62 . In the preferred embodiment, first end  60  pivotally attaches to first support arm  30  to allow the grower to selectively place latch mechanism  10  in the closed position  58  or open position  64 . One such pivot connection utilizes opening  66  sized and configured to connect to a pivot member (not shown) that is bolted or welded to first support arm  30  to allow latch body  56  to pivot towards and away from second support arm  32 . To facilitate the installation of latch mechanism  10  on first support arm  30 , a slot  68  interconnects opening  66  with the outer edge  70  of latch body  56  so the latch body portion  72  between opening  66  and edge  70  can be bent to place latch mechanism  10  on first support arm  30 . 
     The second end  62  of latch body  56  has a mechanism for attachment to the second support arm  32  across path  20  from first support arm  30 . One such attachment mechanism is the use of one or more slots  74  in latch body  56  near second end  62 . The slots  74  should be sized and configured to slide over and securely connect to a connector which is bolted, welded or otherwise attached to second support arm  32 . Slots  74  should be suitable for preventing latch mechanism  10  from accidently releasing from second support arm. As illustrated in FIG. 1, slots  74  can be angled in a direction opposite the direction of the pivoting travel of latch mechanism  10 . The use of multiple slots allows the latch mechanism  10  to be used for different spacing between first  30  and second  32  support arms. Other connection mechanisms can be utilized to accomplish the same objectives. In addition, a locking device can be used to lock slots  74  to second support arm  32 . 
     In the primary embodiment, latch mechanism  10  is installed on to first support member  30  by connecting it directly to first support arm  30  or by bending the body portion  72  of latch body  56  to create access to opening  66 . Latch mechanism  10  is pivoted towards second support arm  32  such that slots  74  at the second end  62  of latch body  56  connect to the connector on the second support arm  32 . The size and configuration of slots  74 , as shown in FIG. 1, prevent latch mechanism  10  from accidently disengaging from second support arm  32 . When the latch mechanism  10  is desired to be removed from second support arm  32 , the grower can provide sufficient upward force to cause latch mechanism  10  to pivot toward first support arm  30 . 
     In the alternative embodiment, the use of which is illustrated in FIG. 5, first end  60  pivotally attaches to first wire member  36  to allow the grower to selectively place latch mechanism  10  in the closed position  58  or open position  64 . One such pivot connection, shown in FIG. 1, utilizes opening  66  sized and configured to allow latch body  56  to pivot around first wire member  36 . To facilitate the installation of latch mechanism  10  on first wire member  36 , a slot  68  interconnects opening  66  with the outer edge  70  of latch body  56 . First wire member  36  can slide through slot  68  to opening  66  or the latch body portion  72  between opening  66  and edge  70  can be bent to place latch mechanism  10  on first wire member  36 . The slots  74  at second end  62  of latch body  56  can be used to attache latch mechanism  10  to second wire member  38  across path  20  from first wire member  36 . The slots  74  should be sized and configured to slide over and securely connect to second wire member  38 . Slots  74  should be suitable for preventing latch mechanism  10  from accidently releasing from second wire member  38 . 
     In use, the latch mechanism  10  of the alternate embodiment is installed on to first wire member  36  by either sliding the wire  36  through slot  68  to opening  66  so that the latch mechanism  10  will pivotally connect to first wire member  36  or by bending body portion  72  of latch body  56  to create access to opening  66  and then closed to prevent wire  36  from exiting opening  66 . Latch mechanism  10  is pivoted towards second wire member  38  such that slots  74  slide over second wire member  38  and tightly engage second wire member  38 . The size and configuration of slots  74 , as shown in FIG. 1, prevent latch mechanism  10  from accidently disengaging from second wire member  38 . When the latch mechanism  10  is desired to be removed from second wire member  38 , the grower can provide sufficient upward force to cause latch mechanism  10  to pivot toward first support row  24 . 
     Latch mechanism  10  is used in trellis system  12  to balance the crop loads that result from the alternate bearing method of growing vine plants  14 , such as grapes, raisins, and the like. In any given year, the bearing row  50  will have a large quantity of vine plants  14  and fruit  52  that, at some time prior to harvesting, will significantly load trellis system  12 . If a completely open trellis system  12  were used, the weight of the plants  14  and fruit  52  would cause the support members to collapse inward toward the path  20  under the bearing row  50 . To prevent the collapse of the support members, the latch mechanism  10  on the renewal rows  48  are placed in the closed position  58 . The weight of plants  14  and fruit  52  place latch mechanism  10  in a tensile loaded condition. During the following year, when the bearing  50  and renewal  48  rows are reversed, the open  64  or closed  58  condition of latch mechanisms  10  are also reversed. 
     The benefits from having a selectively open trellis system  12  are numerous and include the ability to obtain improved growth potential and fruit quality from additional sunshine. One such improvement includes the easier removal of leaves from the top canopy of vines plants  14 . It is well known that significant cost savings and quality improvements can be obtained through dried-on-the-vine methods of growing and harvesting raisins. However, this procedure requires the raisin grapes to be exposed to relatively high levels of sunshine. For trellis systems  12 , the current procedure is to burn the grape vines  14  over the top of path  20  to allow more sunshine in. With the latch mechanism  10  closed on the renewal row  48 , a mechanical fan cutter can be used to cut away some of the vine  14  growth to obtain the improved sunshine characteristics. 
     Another improvement by using a open trellis system  12  for the bearing rows  50  is that the vines  14  and fruit  52  can be more easily covered during inclement weather. It is well known that rain, hail and other natural weather phenomena can significantly harm vine plants  14  or fruit  52 , particularly table grapes. With an open trellis system  12 , supported by latch mechanism  10 , the grower can use mechanical equipment to cover the vine plants  14  and fruit  52  with plastic or other material during the period of inclement weather and remove it after the weather improves. Without the latch mechanism  10 , the plants  14  and fruit  52  are generally left exposed to the elements in alternate bearing fields or the alternate bearing cannot be used, resulting in the loss of benefits from the method of growing vine plants. 
     Although latch mechanism  10  can be used on gable (shown in FIG. 3) or flat (shown in FIG. 4) trellis systems  12 , the greatest benefits will be achieved with the gable systems, due to the general improvement of gable systems over flat systems. For instance, gable systems allow normal sized equipment to go along path  20  without having the fruit  52  hanging so high that it is difficult for field workers to reach the fruit  52  or trim the vine plants  14 . The gable system is generally cheaper to install than the flat system and makes it easier to trim leaves from above and cover with a plastic covering. 
     While there is shown and described herein certain specific alternative forms of the invention, it will be readily apparent to those skilled in the art that the invention is not so limited, but is susceptible to various modifications and rearrangements in design and materials without departing from the spirit and scope of the invention. In particular, it should be noted that the present invention is subject to modification with regard to the dimensional relationships set forth herein and modifications in assembly, materials, size, shape and use.