CROSS REFERENCE TO RELATED APPLICATION AND INCORPORATION BY REFERENCE 
     This application is a continuation-in-part of and claims priority to the previously filed United States of America Utility Patent Application titled PREVEGETATED BLANKET, with an application filing date of Apr. 1, 2010, in the United States Patent and Trademark Office, application Ser. No. 12/798,367, by the same inventive entity, the entirety of said application being incorporated herein by reference in its entirety to provide continuity of disclosure. A Notice of Allowance was granted on application Ser. No. 12/798,367 on Sep. 28, 2012. 
     FIELD OF INVENTION 
     This invention relates to a tray for a prevegetated blanket and more particularly to a tray for growing, forming, and transporting a prevegetated blanket which protects the exposed soil surface from erosion in an efficient manner. 
     BACKGROUND OF THE INVENTION 
     In any construction procedure, soil erosion is usually a major problem. With soil erosion, prevention is always easier than correction. Many ways are known in the prevention of soil erosion. In soil areas, with vegetation growing, the root system of the plants can prevent erosion. So, the faster root growth can occur in the area, the more likely it is that soil erosion can be prevented, or at least minimized. 
     Current erosion treatments are carried out after the site is graded and seed is applied. A site-specific seed type and cover crop are applied by broadcast seeding, slip seeding, drill seeding, or hydro-seeding. With favorable weather conditions or supplemental watering in controlled increments, the seed source may start to establish within three or four weeks. The soil can then be stabilized with the living plants. In the meantime, this practice presents a great potential problem for causing soil loss by erosion, due to the period of no vegetation and lack of emerging root growth. 
     Typical seeds for cover crops include, but are not limited to annual rye, fescue and spring oats. Seeding generally takes longer to establish the root system to minimize or prevent erosion. Those plants usually require two or three growing seasons for maturity and the establishment of good ground cover. In normal practices, job site and outside conditions affect the success of seed growth. Heavy rain or hot climates can cause the seed or soil to erode without proper maintenance. 
     In extremely difficult climates, additional water and herbicide treatments are necessary to establish the seed and create a root base to minimize erosion. If the site is already suffering from damage, such as erosion problems, additional soil and seed applications may be necessary. Such actions add greatly to the expense of erosion prevention. 
     Soil customarily contains tremendous amounts of seed sources that produce weeds. Once the soil is disturbed, new annual weeds will begin to germinate, and overtake a cover crop and the native seed source. Weeds are very undesirable. Avoidance of a weed crop is very desirable. Quick growth of desired vegetation is a very desirable method of avoiding a weed crop. 
     Currently, live plugs, which are small pieces of desired vegetation, are the only way to produce immediate vegetation coverage to compete with weed seeds. Planting the live plugs is labor-intensive. The plugs themselves are also costly. Then, the maintenance of the plugs is a problem. 
     Additionally, because of short growing seasons in the upper Midwest, the success of the native species and its growth will be shortened. It will therefore take more growing seasons to have any native species function as the erosion-preventing ground cover. In that case, treatments to prevent extreme weed competition can include controlled burns or herbicides. Such treatments can cause more problems than they solve. A controlled burn requires a fire department presence for reasonable safety. Herbicides have environmental consequences, even with careful application thereof. 
     Normally when exposed soil is to be seeded after the grade, a seed type is applied by either broadcast or hydro-seeding. But at application, the specified seed is just that, seed. It has not developed into an erosion preventing plant. Thus, it usually will take a three to four week period, under good growing conditions, to produce a cover crop. Seed generally takes longer to establish than living plants to take hold and root. 
     Also, a seeding process is usually fighting many uphill battles. Inclement weather types, such as heavy rains, extreme heat or both, may prevent seeds from rooting or sprouting. Even under an erosion control blanket, seeds still have those problems. If the construction site is already wet or has a fast and unpredicted rise of water flow, because of urban run off or naturally occurring stream rising or falling, it creates additional issues for seeds. Other problems for seeds include spikes in runoff or rain fall which can prevent full establishment of the seed. 
     If the seeding processes needs to be repeated, much more labor, expense, and tremendous efforts are required to repeat ground preparation and to re-seed. In contrast, if the initial seeding process is successful, the originally installed seeds require constant maintenance; such as adding new soil, reseeding, using additional water or re-blanketing as a special erosion control measure. These ongoing maintenance operations add a tremendous additional expense. If the project is successful for normal operation standards, weed treatments such as herbicides or cutting still must be done to allow access for Native foliage to grow. Then, in most of the United States, the summer heat arrives for many weeks. Native foliage, being succulent and young cannot fight the annual weed competition. 
     Such plantings are not acceptable and will not get the appropriate signing off as successful by the permitting authority, engineers or the contractor. General contractors and subcontractors are not paid until the project is approved, thereby restricting cash flow. 
     While this may seem odd, under normal practices, this is usually how commercial jobs operate. Because of unit costs up front, ground cover installation prices per unit are very expensive. No appropriate solution is currently available. 
     The true price per unit is high and still may take years to see true success. In the interim, soil loss and natural waterways, wetlands, or other areas are polluted. Remedies therefore occur at a large cost. Compounding daily across the United States is a large scale environmental problem from non source point pollution. 
     It is very necessary to create an alternative process to limit loss exposure and create situations to have a better chance of success; such success including, but not limited to, reduced overall herbicide use and limiting the damage of storm events, thereby allowing credible changes in plant community establishment faster and protecting our environment. To that end, it is very desirable to have an efficient method of getting desired vegetation in a desired place quickly. It is furthermore valuable to be able to control erosion and produce native grass or turf grass on difficult sites or erodible soils quickly and efficiently with reduced labor and maintenance requirements. 
     Attempts to solve some of these problems with vegetated blankets can also be a problem. It is difficult to produce a proper blanket for control of erosion. Additionally, it is difficult to move the blankets to a desired location. Then application of the blanket to the desired surface can be complicated and difficult. 
     Traditionally, landscape blankets are rolled and transported to an installation site via trucks. Rolled or block cut sod is rolled and transported via truck after cutting established root growth. Further, in the transportation process, roots are compressed and further damaged. 
     It will be a useful invention to create a tray which allows a prevegetated blanket to form and grow in the tray. Then, the tray can be transported to the job site via truck without rolling the prevegetated blanket or cutting or damaging established root growth. 
     SUMMARY OF THE INVENTION 
     Among the many objectives of the present invention is the provision of a prevegetated blanket providing desired seeds and low maintenance to a desired area of erodible soil. 
     Another objective of the present invention is the provision of a prevegetated blanket, which is easily maintained. 
     Yet another objective of the present invention is the provision of a prevegetated blanket, which minimizes environmental damage. 
     Still another objective of the present invention is the provision of a prevegetated blanket, which provides for at least reduced herbicide treatment. 
     A further objective of the present invention is the provision of a prevegetated blanket, which uses minimal water. 
     A still further objective of the present invention is the provision of a prevegetated blanket, which-minimizes erosion. 
     Yet a further objective of the present invention is the provision of a prevegetated blanket, which provides for no herbicide treatment. 
     Another objective of the present invention is the provision of a prevegetated blanket, which is easily transported. 
     Yet another objective of the present invention is the provision of a prevegetated blanket, which is easily installed. 
     A still further objective of the present invention is the provision of a tray which facilitates ease of growth, transportation, and installation. 
     These and other objectives of the invention (which other objectives become clear by consideration of the specification, claims and drawings as a whole) are met by providing a tray for a prevegetated blanket which allows for ease of growth, transportation, and installation of the blanket and does not cause harm or further damage to the roots during transportation. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  depicts a box diagram of the structural assembly  100  of this invention. 
         FIG. 2  depicts an exploded, perspective view of the structural assembly  100  for the live blanket  114  and tray  130  of this invention. 
         FIG. 3  depicts a side, cut away view of live blanket  114  with established growth, based on  FIG. 2 . 
         FIG. 4  depicts a perspective view of the structural assembly  100  of this invention on a site  102 . 
         FIG. 5  depicts tray  130  for the structural assembly  100  of this invention. 
         FIG. 6  depicts tray  130  for the structural assembly  100  of this invention as storage stack  170 . 
         FIG. 7  depicts tray  130  for the structural assembly  100  of this invention as transportation stack  200 , on truck  210 . 
         FIG. 8  depicts a top view of tray  250  for the structural assembly  100  of this invention. 
         FIG. 9  depicts a side view of tray  250  in a stack of trays  252  for the structural assembly  100  of this invention. 
         FIG. 10  depicts a cut away view of tray  250  in a stack of trays  252  for the structural assembly  100  of this invention. 
         FIG. 11  depicts a side view of tray  250  for the structural assembly  100  of this invention. 
         FIG. 12  depicts a perspective, cut away view of tray  250  in a stack of trays  252  with the bottom tray  250  depicted in phantom. 
         FIG. 13  depicts a perspective, cut away view of tray  250  in a stack of trays  252  with the bottom tray  250  depicted in phantom. 
         FIG. 14  depicts a side view of tray  250  with removable rail  264 . 
         FIG. 15  depicts a side view of tray  250  for the structural assembly  100  of this invention. 
         FIG. 16  depicts a perspective, cut away view of tray  250  in a stack of trays  252  with removable rail  264 . 
     
    
    
     Throughout the figures of the drawings, where the same part appears in more than one figure of the drawings, the same number is applied thereto. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to several embodiments of the invention that are illustrated in accompanying drawings. Whenever possible, the same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms such as top, bottom, left, right, up, down, over, above, below, beneath, rear, and front, may be used with respect to the drawings. These and similar directional terms are not to be construed to limit the scope of the invention in any manner. The words attach, connect, couple, and similar terms with their inflectional morphemes do not necessarily denote direct or intermediate connections, but may also include connections through mediate elements or devices. 
     Components of the prevegetated blanket of this invention prevent erosion and grow a living membrane for native and cover crops in a controlled environment in a weed free state. Then, the prevegetated blanket is transferred to a specific site and installed immediately after soil is prepared. By the end of Day 5, a living plant matrix is installed. Roots will be established in the soil within about two days of blanket installation, because the roots already exist. Plant heights will vary on species but are usually about 7.6 centimeters (three inches) to 15.2 centimeters (six inches) tall upon installation and provide an immediate good cover crop. 
     Weed seeds are not exposed to sun and are covered, thereby at least substantially reduced as a living crop. In fact, weeds can now be kept to a dormant state. Also, erosion caused by even heavy rainfall will be decreased by 50 percent upon installation: 
     This process uses improved erosion control methods in place of standards followed by engineers across the country. Additionally solar heat and sun, organic watering along with standard growth media, such as top soil, and neutral root media permit plants to thrive. They are cost effective and provide at least eighty percent (80%) cover. Thus, these are living plant communities born to prevent erosion. 
     A substrate receives a growth medium or a topsoil layer and desired seeds. Preferably, the substrate is a fibrous, non-woven substrate, or a fiber pad. Such substrates are known as erosion control blankets. At least one net layer supports the substrate and keeps desired materials therein or thereon. The net layer may be polyethylene, polypropylene, or another suitable polymer, or copolymers thereof. A polypropylene net appears to be more durable and is preferred. More preferred is to have the net be of biodegradable material. The net, with its 5 lines and openings, provide structure and strength for the prevegetated blanket, without interfering with the purpose thereof. 
     The prevegetated blanket utilizes significantly less top soil than previous, conventional methods. Due to the reduction in the amount of top soil, the prevegetated blankets weigh significantly less and can be carried to job sites where vehicles cannot travel. For example, a vehicle may not be able to reach near the edges of ponds that have a steep downhill grade toward the pond. In this environment, the ground may be soft and watery and the vehicle may risk getting stuck. The lighter prevegetated blanket can be carried to the desired location and installed thus alleviating this potential problem. 
     Moreover, more square meters of the present, lighter prevegetated blankets can be legally carried on a semi truck or trailer and transported to a job site, reducing the number of trips between the greenhouse or other growing facility and the installation site. Finally, prior blankets tended to shrink between the process of cutting, transporting, and installing at the job site. The present prevegetated blankets do not shrink during this process and thus, even more square meters of surface coverage can be transported and installed at a job site on a single semi truck or trailer. 
     In previous methods, 2.5 centimeters (1 inch) to 3.8 centimeters (1.5 inches) of dry weight of growth medium such as peat or top soil is utilized. However, in the present invention, 0.3 centimeters (⅛ inch) to 1.9 centimeters (¾ inch) of growth medium such as top soil is used. In the preferred embodiment, no more than 1.3 centimeters (½ inch) of growth medium such a top soil is used. 
     The following is intended as an illustrative example of the great weight reduction provided by the present invention. In the present invention, live blankets containing 3.34 square meters (36 square feet) of material weigh between 36.29 kilograms (80 pounds) and 56.7 kilograms (125 pounds). In previous methods, sod blankets containing 0.93 square meters (10 square feet) of material weigh 36.3 kilograms (80 pounds) to 38.56 kilograms (85 pounds). For a direct comparison of the approximate weight difference between the previous and present methods, the previous embodiment weights must be multiplied by 3.6 to account for the difference in square meters. For the same amount of material, the previous blankets weigh between 130.63 kilograms (288 pounds) and 138.8 kilograms (306 pounds). 
     Also, previous methods were severely limited as to the type of plant they are able to grow and transport to installation sites. Previous methods were substantially limited to Kentucky Bluegrass, Ryes, Fescues, Bent Grasses, and Bermuda Grasses. In contrast, the present invention is nearly unlimited as to the plants, seeds, grasses, or bulbs that can be grown, transported and installed. The present invention can handle Kentucky Bluegrass, Ryes, Fescues, Bent Grasses, and Bermuda Grasses. Also, the present invention can grow, transport, and install an unlimited variety of other seeds and plants. Some examples include, but are not limited to, sedges such as Prairie Sedges, Bristly Sedge, Fox Sedge, and Fringed Sedge, native grasses such as Sweet Grass, Indian Grass, Wood Reed Grass, and June Grass. The present invention can also handle wet mesic plant varieties, woodland grasses, prairie plants, wildflower, and annuals. This list, for the present invention, is intended to illustrate the wide variety of seeds that can be grown, transported, and installed with this invention. However, it by no means is intended to limit the present invention to these seeds alone. 
     Referring now to  FIG. 1 , structural assembly  100  has seed  110  and, in certain cases plant plugs, applied to a fiber pad or fibrous substrate  120 . Fiber pad and fibrous substrate  120  are used interchangeably throughout the application but refer to the same component. Between the seed  110  and fiber pad  120  are applied a growth medium  112 , such as top soil, and top net  118 , preferably of polypropylene. Fiber pad  120  has growth medium  112  and the top net  118  on a top surface thereof and a bottom net  122 , preferably of polypropylene, on a bottom surface thereof to form a static prevegetated blanket  116 . This structure, by adding seed  110  to the fiber pad  120  forms a live blanket  114  of the prevegetated blanket  116 . Fertilizer may also be applied to the seed mix  110  to aid in growth. 
     Growth medium  112  can be a variety of substances and any suitable substance for providing nutrients and a proper growth environment for the plants is encompassed by this disclosure. In one embodiment, the use of top soil can be substantially limited as to reduce the weight of the live blanket  114  during transport and installation. Thus, the live blanket  114  can be installed in places that are hard to reach by truck or trailer  210 . In other embodiments, some suitable examples of growth medium  112  include top soil, sphagnum, vermiculite, or a premixed growing media. Vermiculite and similar materials are very useful for water retention in the live blanket  114 . Many of these growth mediums  112  are sold in bulk compost soil establishments and starter nutrients. As can be clearly seen, there is great flexibility and advantages in the use of growth medium  112 . 
     In the preferred embodiment, fibrous pad  120  is 4 millimeters (0.157 inches) to 14 millimeters (0.551 inches) thick. In a more preferred embodiment, fibrous pad  120  is 5 millimeters (0.197 inches) to 13 millimeters (0.512 inches) thick. In the most preferred embodiment, fibrous pad  120  is 6 millimeters (0.236 inches) to 12 millimeters (0.472 inches) thick. 
     Adding  FIG. 2  and  FIG. 3  to the consideration, support for the live blanket  114  comes from a tray support, preferably in the form of tray or tray support  130 . Tray  130  is a rectangular or square open tray with edges and a t-grid  132  at a bottom portion thereof for support of live blanket  114 . At a top edge of tray  130  is a top tray interconnect  134 . Within a side of tray  130  is a grip slot  136 . Grip slot  136  provides for lifting tray  130  or a stack thereof manually, or with a forklift or suitable device (not shown). T-grid  132  is low enough in tray  130  to provide a growth space  138  for grass or other plants  126  of live blanket  114 . 
     Top tray interconnect  134  cooperates, preferably in a male to female relationship, with a bottom tray connect  140  on a bottom edge thereof in order to permit nesting or stacking of a plurality of trays  130 . Top tray interconnect  134  cooperates with a bottom tray connect  140  to provide a stable stack or nestable stack of trays  130 . T-grid  132  is spaced from a bottom of tray  130  in order to provide a root space  148 , for roots  124 , between a pair or a plurality of stacked trays  130 . 
     The tray  130  may be supported on a supply of smooth aggregate  150  ( FIG. 2 ), which can also serve as a water retaining substance, as the live blanket  114  is assembled therein. However, vermiculite and similar substances are the preferred water retaining substance. Alternatively, the live blanket  114  may be assembled as a larger structure and cut to fit the tray  130 . The aggregate  150 , with the T-grid  132 , supports the live blanket  114 . The watering of the live blanket  114  may be facilitated thereby. 
     With the further consideration of  FIG. 4 , use of a series of the live blankets  114  becomes clear. After live blanket  114  is removed from tray  130 , roots in root space  148  (as shown in  FIG. 3 ) are applied directly to the soil on site  102 . Staples  158 , preferably of the landscape type, support the series of live blankets  114  in a desired position. At the edge of each live blanket  114 , which adjoins another live blanket  114 , is an overlapped edge  160  of the series of live blankets  114 . Such overlapping encourages water to run down the live blanket  114 , without eroding the same. At the edge of site  102  is a tucked edge  162  of the series of live blankets  114 , which does not adjoin another live blanket  114 . 
     Now adding  FIG. 5  to the discussion, tray  130  has t-grid  132  near a bottom portion thereof, to support live blanket  114 . At a top portion of tray  130  is top tray interconnect  134 . Top tray interconnect  134  serves as the male portion of the nesting capability for a stack of trays  130 . Bottom tray connect  140  ( FIG. 3 ) serves as the female portion of the nesting capability for a stack of trays  130  in cooperation with top tray interconnect  134 . Grip slot  136  permits manual or forklift (not shown) lifting of tray or trays  130 . 
     Stacking advantages become even more clear with the consideration of  FIG. 6  and  FIG. 7 . Live blanket  114  within tray  130  can be stacked for storage or transport. Storage stack  170  of trays  130  is shown in  FIG. 6 . Transportation stack  200  shows a load of a plurality of trays  130  in a series of stacks of ten trays  130  on truck  210 . The nesting capability for a stack of trays  130  is thus illustrated. Once installation of the live blanket  114  at a job site is complete, empty tray  130  is returned to the original greenhouse or other growing site and is reused and recycled for future blankets  114 . 
     Stacking of trays  130  on truck  210  has added benefits. The upper trays  130  protect the live blankets  114  in lower trays  130  from heat, sun, wind, and other environmental conditions. Stacking of trays  130  especially helps protect roots  124  from drying and destroying live blanket  114 . Stacking of trays  130  offers great advantages and flexibility in transportation and installation of live blankets  114 . 
     Now adding  FIG. 8 ,  FIG. 9 ,  FIG. 10 ,  FIG. 11 ,  FIG. 12 ,  FIG. 13 ,  FIG. 14 ,  FIG. 15 , and  FIG. 16  to the consideration, an alternate embodiment of tray  130  can be clearly seen. Tray  250  functions similarly to tray  130  as shown and described in the earlier embodiments. Also, individual trays  250  can form a stack of trays  252  similar to the stack of trays  170  seen in earlier embodiments. 
     Tray  250  has t-grid  254  which has similar placement as seen in  FIG. 2  and  FIG. 3 . T-grid  254  is positioned in tray  250  in grid position  294  to allow appropriate root space  148  between t-grid  254  and bottom edge  290 . In the growing process, tray  250  can be placed onto and into smooth aggregrate  150  with the t-grid  254  sitting directly on the smooth aggregrate  150  to provide ample space for the growth of roots  124  and ample space for transportation in a nestable stack  252  without harm to roots  124 . Also, t-grid  254  is placed in grid position  294  in tray  250  to provide proper growth space  138  between t-grid  254  and upper edge  292  to allow for a plurality of trays  250  to be formed in a nestable stack  252  without harming the growth of the live blanket  114 . 
     Also, t-grid  254  allows roots  124  to assume the t-grid pattern and grow in a diamond or quilted pattern  256 . Diamond or quilted pattern  256  provides negative space  258  in the areas roots  124  do not grow due to the interference from the t-grid  254 . Once live blanket  114  is installed on site  102 , the diamond or quilted pattern  256  of roots  124  aids in handling and filtering rain or water and helps to prevent erosion and destruction of live blanket  114 . Negative space  258  of roots  124  absorbs excess rain or water and also filters it in an efficient manner. Diamond or quilted pattern  256  helps prevent live blanket  114  from sliding out of place or being destroyed after installation at site  102 . 
     Tray  250  has rails  262  to strengthen and stabilize tray  250  and prevent inward or lateral distortion of the shape of lower trays  250  from the weight of a stack of trays  252 . Rails  262  can be a permanent part of tray  250  or can be a separate and removable addition as seen in removable rails  264 . 
     Referring specifically to  FIG. 8 ,  FIG. 9 ,  FIG. 10 ,  FIG. 11 ,  FIG. 12 , and  FIG. 13 , rails  262  are a permanent fixture in t-grid  254 . Rails  262  are preferably aluminum but can be made of any suitable material to add strength and support to tray  250 . Rails  262  rise above t-grid  254  but do not interfere with the nesting abilities of the stack of trays  252 . 
     Referring specifically to  FIG. 14 ,  FIG. 15 , and  FIG. 16 , the function and structure of removable rails  264  can be clearly seen. Removable rails  264  are preferably aluminum but can be made of any suitable material to add strength and support to tray  250  as it is stacked in stack of trays  252 . Removable rail  264  has lips  266  on opposing sides which rest over upper edge  292  of tray  250  to secure removable rail  264  in place. 
     Tray  250  has at least two but preferably four hand grips  260  which allow the tray  250  to be manually carried. For example, hand grips  260  allow workers to remove a single tray  250  from truck  210  and carry the tray  250  to areas not accessible by truck  210  or a fork lift (not shown) such as steep banks surrounding bodies of water or extremely wet areas. 
     Tray  250  has at least two fork lift channels  270  to receive the spades of a forklift (not shown) to aid in transportation and movement of tray  250 . Forklift channels  270  are positioned at the bottom edge of tray  250 , beneath the t-grid  254 , to allow the lifting of tray  250  with minimal invasion of the root space  148  to protect the roots  124 . Tray  250  is stacked in the reverse manner as shown in  FIG. 7  for tray  130 . Trays  250  are stacked in preferably two rows on the longitudinal axis of the flatbed of truck  210 . Forklift channels  270  face the external lateral aspect of the flatbed truck  210  rather than longitudinally as shown in  FIG. 7  for tray  130 . 
     Tray  250  can be stacked onto another tray  250  to form a stack of trays  252 . Each tray  250  has a top tray interconnect  280  and a bottom tray connect  282  to aid in forming stable stacks of trays  252 . Top tray interconnect  280  is located on the upper perimeter of tray  250  while bottom tray connect  282  is a recess located on the lower perimeter of the inside edge  284  of tray  250 . Top tray interconnect  280  is a lip with preferably a corrugated pattern and acts as the male portion. Bottom tray connect  282  is a recess and has the same, matching corrugated pattern of top tray interconnect  280  and receives the top tray interconnect  280  as the female portion in the male to female relationship. 
     The corrugated pattern of top tray interconnect  280  is interrupted to accommodate forklift channels  270 . This interruption allows the spades of the forklift to access forklift channels  270  without interference but still allows for a secure and stable connection between top tray interconnect  280  and bottom tray connect  282 . 
     The stack of trays  252  is nestable due to the placement and alignment of the bottom tray connect  282  on the top tray interconnect  280 . Top tray interconnect  280  of the lower tray  250  is received by the bottom tray connect  282  of the upper tray  250  and the two trays  250  interlock and form a secure stack of trays  252 . The bottom tray connect  282  of the upper tray  250  is able to receive the top tray interconnect  280  of the lower tray  250  and this male to female relationship reduces the overall height of the stack of trays  252  as portions of the upper tray  250  and the lower tray  250  share the same space. 
     On the other hand, it is also possible to form a stack of trays  252  without aligning the top tray interconnect  280  of the lower tray  250  and the bottom tray connect  282  of the upper tray  250 . If either the upper tray  250  or the lower tray  250  is rotated either 90 degrees or 180 degrees, the alignment of the lip of the top tray interconnect  280  of the lower tray  250  is not able to be received by the recess of the bottom tray connect  282  of the upper tray  250 . The resulting stack of trays  252  is not nestable due to a reversal of the corrugation pattern on the opposite side resulting from the 180 degree turn or the nonalignment based on the 90 degree axis alignment. This non-nestable relationship provides for rapid disassembly of the stack of trays  252 . 
     Within the current national and stated standards and practices for preventing erosion, growing a living prevegetated erosion control blanket will increase the establishment of a native plant source or cover crop. By using this live blanket  114 , weed seeds will remain dormant. Also, soil erosion will be reduced by fifty percent, and the vegetative cover will be increased by eighty percent in a minimum amount of time. 
     The process of growing the prevegetated blanket is designed using existing erosion control components and standards currently in place in a controlled environment. By using specific existing growing media in a non-soil hydroponics root mass with this prevegetated blanket, vegetation and root stabilization is minimized to two to three weeks. This time compressed system greatly reduces erosion. 
     A variety of components are suitable for use for the prevegetated blanket. Preferred components of the prevegetated blanket are as follows: 
     (1) Aggregate: Stone smooth, round, with a diameter of about 0.6 centimeter (0.25 inch) to 2.5 centimeters (0.75 inch) to prevent root growth resistance. 
     (2) Erosion control blankets are fibrous substrates or blankets of vegetable fibers. Typical such blankets include, but are not limited to the following commercially available blankets: C125 core fiber blanket, DC 250 double net coconut or core blanket, MC 250 double net core matrix blanket, C32 core fiber blanket, TRM C 350 turf reinforcement core matrix blanket and a bio D SCF 30 core stitched blanket with photo degradable netting. 
     (3) Growing Medium: Sphagnum for organic matter, vermiculite for water retention or water retaining substance and topsoil for seed or a pre mixed growing media. These growth mediums are sold in bulk compost soil establishments as well as starter nutrients. 
     (4) A seed cover crop including but not limited to wildflower mix, pure mesic, native, herbs, no mow turf, fescue, annual or perennial rye may be used. 
     Depending upon the blanket application, supplemental plant plugs may be used. The application of the prevegetated blanket will determine the seed source used. 
     The following is an example of a method of manufacturing or growing a prevegetated blanket that is substantially similar to the method that utilizes tray  130  or tray  250 ; the method below does not utilize a tray system but is otherwise the same. Manufacturing or growing procedures for the prevegetated blanket include: 
     Step 1: Growing Area Preparation for the Blanket. 
     An aggregate base having a thickness between 10 centimeters (four inches) and 33 centimeters (twelve inches) is used. This prevents weeds from germinating up through the aggregate base. 
     Step 2: Blanket Preparation. 
     An erosion control blanket between about 2.4 meters (eight feet) wide and 34.1 meters (112 feet) in length are laid out on top of the aggregate. A growing or growth medium or media are then preferably applied on the surface of the blanket at a thickness of about 0.5 centimeter to about 4 centimeters. More preferably, the growing or growth medium or media is applied on the surface of the blanket at a thickness of about 0.5 centimeters to about 3 centimeters. Most preferably, the growing or growth medium or media is applied on the surface of the blanket at a thickness of about 0.5 centimeters to about 1.5 centimeters. Most desirably preferred is thickness of about 1.0 centimeters (0.375 inch). The desired seed mix is then applied on the surface of the growing media. After seed, fertilizer is then applied. 
     Step 3: Growth Period. 
     Once the components are installed on the aggregate, the live prevegetated blanket is then preferably watered at a rate of about of 1 liter to 3 liters per square meter. More preferably, the live prevegetated blanket is then preferably watered at a rate of about of 1.5 liters to 2.5 liters per square meter. Most preferably, the live prevegetated blanket is then preferably watered at a rate of about of 1.7 liters to 2.1 liters per square meter. Continued watering depends on the seed applied, anywhere from two liters to 3.9 liters (one gallon) per 0.1 square meter (one square foot) twice a week. To harden the crop before shipment, water is reduced slowly by unit volume for a three to a four-day span. 
     Within three weeks, a root depth of 1.2 centimeters (0.5 inch) to 2.5 centimeters (about one inch) is established with a shoot height between 1.2 centimeters (0.5 inch) to 5.1 centimeters (about two inches). The product is then ready for shipment to a specific job site for installation. 
     Step 4: Shipping. 
     About 9.1 meter (30 feet) sections are cut, shaken lightly to remove any bonded aggregates and lifted to a trailer for transport. The aggregate stays at the greenhouse or other growing facility. The blanket is watered and tarped to prevent moisture loss and damage caused by wind and shipped to a site. The live, prevegetated blanket is installed following all standard installation methods. 
     Step 5: Installation. 
     Installation practices follow erosion control blanket standards. 
     In conclusion, installing a prevegetated erosion control blanket is easier and faster to install with immediate vegetation and is aesthetically more complete visually for a compliance sign off, required for payment on construction projects. 
     In the following examples, which are intended to illustrate without unduly limiting the scope of this invention, all parts and percentages are by weight unless otherwise indicated. 
     Example 1 
     A drainage ditch is designed to carry parking lot water as runoff to a wet detention area. Grading is done to create a swale to carry water to a crested wetland. Under permits and an engineering plan, the site is seeded. Then an applied erosion control measure or blanket is applied to secondarily protect the seed of a specified plant from moving or eroding under the blanket. 
     About one week later, about one inch of rain washes away the seed, because there are no growing roots from seed to prevent the washing away or erosion. After a month, the crop of annual weeds appears, and new seed plants are forced out because of compaction or competition. 
     Example 2 
     The procedure of Example 1 is repeated, except that a live prevegetated blanket using the same seed as Example 1, replaces the seed and the blanket of Example 1. About one week later about one inch of rain leaves the seed intact because there are growing roots from seed to prevent erosion. After a month, the crop of new seed plants is well settled, and the annual weeds common to the area are absent. The use of the live prevegetated blanket provides the successful end result of this example. 
     This application—taken as a whole with the abstract, specification, claims, and drawings—provides sufficient information for a person having ordinary skill in the art to practice the invention as disclosed and claimed herein. Any measures necessary to practice this invention are well within the skill of a person having ordinary skill in this art after that person has made a careful study of this disclosure. 
     Because of this disclosure and solely because of this disclosure, modification of this tool can become clear to a person having ordinary skill in this particular art. Such modifications are clearly covered by this disclosure.
A prevegetated blanket is formed, grown, and transported to an installation site in a tray specifically suited for this purpose. Growth in a tray system offers an improved and protected root system and provides for ease of transport and installation. The tray has side walls and a t-grid floor to permit growth of the blanket. The tray also has interlocking capabilities for nestable or non-nestable stacking. After growth in a controlled environment, the prevegetated blanket with the tray is transferred to a specific site and installed immediately after soil is prepared. Due to the tray design, the product is light weight and facilitates ease of handling with minimal disturbance of the root structure.