Background of the Invention
This invention relates to a fibrous web for planting seeds, the method of sowing an area of soil with seeds by using the fibrous web and an apparatus for producing the fibrous web.
The conventional planting of grass, flower and other seeds frequently is inefficient. Particularly in connection with the establishing of new lawns, the conventional sowing of seeds results in a substantial waste of seed and, moreover, is time-consuming and tedious.
It is an object of the present invention to provide a fibrous web for planting seeds the use of which is easier and less wasteful of seeds than the conventional sowing of seeds.
It is a further object of the invention to provide a method of sowing an area of soil with seeds comprising using the aforementioned web.
It is also an object of the invention to provide an apparatus for producing the aforementioned web.
Other objects and advantages of the invention will be apparent to one of ordinary skill in the art from the description of the invention hereinbelow.
Before the invention is described, a review of prior art in the general field of the invention will be given.
In U.S. Pat. No. 2,909,003, seeds are distributed over an adhesive-free open lofty web of textile fibers and in the interstices thereof.
U.S. Pat. No. 3,863,388 relates to a form of turf in which seeds are germinated in a rooting medium, namely soil or peat or exfoliated minerals or interconnecting open cell decomposable cellular resin foam materials supported on a mesh overlying a sheet or other solid structure.
U.S. Pat. No. 3,914,901 relates to a mat roll for starting a lawn or other vegetation comprising a web sheet having viable seeds embedded therein, the sheet comprising sphagnum peat moss and a binder such as sodium silicate.
U.S. Pat. No. 2,826,865 relates to a seed carrier having a laminated structure, each layer being composed of heterogeneously arranged natural cellulosic or synthetic fibers, the layers being sewn together with loosely twisted thread.
U.S. Pat. No. 3,160,986 relates to a seed carrier in the form of a plastic film onto which the seed is held by means of a water-soluble adhesive.
U.S. Pat. No. 3,583,099 relates to rigid tiles containing seeds. The tiles are made of clay and binder.
U.S. Pat. No. 3,516,196 relates to a seed mat comprised of a biodegradable paper sheet coated with an asphalt adhesive binding seeds to the upper surface of the biodegradable paper sheet.
U.S. Pat. No. 1,971,504 relates to a seed carrier comprising a cotton netting or paper backing supporting a layer of water soluble fertilizer, a flexible plastic layer and flexible adhesive adhering the seeds to the plastic layer.
U.S. Pat. No. 3,303,609 relates to a mixture including thin-walled hydrophilic regenerated cellulose fibers, wood fibers, fertilizer and grass seed.
U.S. Pat. No. 3,292,307 relates to a mixture including fiberglass, cellulose fiber, seeds and fertilizer.
U.S. Pat. No. 3,557,491 relates to a permeable fabric or film treated on one side with a carrier containing seeds, the fabric being coated with asphalt on the other side or being at least partially saturated with asphalt.
U.S. Pat. No. 3,888,041 relates to a knitted fabric mulch into which may be incorporated seed tapes.
U.S. Pat. No. 3,889,417 relates to a plastic foam carrying seeds.
U.S. Pat. No. 2,605,589 relates to a sod unit in which seeds are carried on humus or peat moss covered with sand and overlying a plastic mesh.
Canadian Pat. No. 811,081 relates to compressed peat containing seeds.
Summary of the Invention
According to the invention, there is provided a fibrous web for planting seeds, consisting essentially of a mat of randomly oriented, unmodified, natural straw-like cellulosic fibers, viable seeds, water soluble adhesive and fertilizer.
The terminology "unmodified, natural" is intended to exclude fibers which initially were natural but are presently not in a natural state, such as regenerated cellulosic fibers. The term "straw-like" is intended to include straw and similar materials which are readily recognizable as being straw-like, such as corn husks and other wastes from the harvesting of crop lands. These are characterized by being of relatively long fiber length and relatively rigid but flexible and, therefore, forming webs with a considerable degree of permeability without the necessity of puncturing or similarly processing the webs.
The preferred "straw-like" material is from stalks of grain which are single, coarse, dry stems produced after threshing and are chopped to an average length of one and half inches and ranging from approximately three-quarters of an inch to two inches.
According to another aspect of the invention, there is provided a method of sowing an area of soil with seeds comprising laying over the area the aforementioned web. The soil generally requires no preparation at all or, at most, a moderate surface breaking.
The seeds selected are viable so that they will germinate after the product of the invention has been laid onto the soil.
Typical water soluble adhesives which may be used according to the present invention are protein and protein derivative adhesives including those made from casein, zein, soybean proteins, and other proteins and the types of glues made from hides, bones, and so forth, fish glues from fish offal, and those made from blood albumen, adhesives made from materials such as starch and vegetable gums, comprising adhesives made from starch and processed starch, the dextrins, and the water soluble gums such as gum arabic, ghatti, tragacanth, Indian gum and the like. Cellulose adhesives which are principally cellulose derivatives such as methyl cellulose, ethyl cellulose and sodium carboxymethyl cellulose.
The preferred adhesive is polyvinyl acetate which is flexible when dry. This glue is available through Adhesive Compounds, Inc., Des Moines, Iowa.
Common water soluble fertilizers may be used in the present invention. Typical of these are ammonium sulfate, calcium nitrate, ammonium nitrate, urea, monocalcium and ammonium phosphates, single superphosphate, wet-process orthophosphoric acid, triple superphosphate, ammonium phosphates, nitrophosphates, nonorthophosphates and so forth and various mixtures of the foregoing.
The seeds themselves may be any grass, flower or other seeds which it is desired to sow. Generally speaking, it is anticipated that the present invention will find its greatest utility in the establishment of lawns and flower beds, but it certainly is not limited to these particular applications.
The rolled seeded and fertilized straw mulch mat derives its entire structural strength and unity from the randomly oriented straw pieces bonded together by the adhesive in a fluffy state wherein the seed is only on one side of the mat, the side facing downwardly when the mat is applied to the ground and is secured to the individual straw pieces by adhesive on the straw making spot contact only with the seed and fertilizer.
The invention will now be further described by reference to a specific, preferred embodiment thereof, as illustrated in the accompanying drawing.
Brief Description of the Drawing
The drawing is an isometric view, in partially schematic form, of an apparatus for producing a fibrous web in accordance with the invention.
Description of the Preferred Embodiment
The apparatus illustrated in FIG. 1 includes a bin 1 for holding chopped mulch such as straw which ultimately forms the base for the product of the invention. A conduit 2 including conventional elevator and transport means conveys the dry straw from the bin 1 to a conventional feed hopper 3 which evenly distributes the straw in a fluffy condition onto the top surface of a conveyor belt 4 which is driven by a variable speed motor 13 in the direction away from the bin 1.
The distributed straw on the conveyor belt 4 passes beneath a pair of opposed augers 5 that firm and level the straw to form a mat of substantially uniform thickness. A variable speed motor 14 drives the augers. Another motor 15 can raise and lower the augers thereby to adjust the thickness of the mat being formed.
Downstream from the augers 5, a sprayhead 6 applies by means of a pump 7 from a reservoir 12 a hot aqueous solution of water soluble glue at a pressure of approximately 10-12 p.s.i. Thereafter, granular fertilizer and grass seed are gravity fed from respective hoppers 8 and 9 into spot contact with the adhesive on the straw. The thus prepared product according to the invention, still wet from the adhesive, is fed into a drying tunnel 10 surrounding a portion of the upper run of the conveyor belt 4.
The amount of adhesive used is only enough to provide the spot contact bonding between contiguous fibers and with the granular material.
A conventional heating oven 11 provides hot air for the drying tunnel 10. Preferably, two 400,000 b.t.u. gas-fired furnaces are used. Hot air is fed to the tunnel 10 through ducts 18 and air is recirculated from near the downstream end of the tunnel 10 to the oven 11 through return duct 17. Downstream from the tunnel 10, a conventional cutter 16 cuts the finished mat product of the invention into pieces of desired length.
The preferred resulting product is three-sixteenths inch-one-quarter inch in depth and includes five to eight straws in thickness. The mat will weigh from three and a half to four and a half pounds per fifty square feet including straw, adhesive, fertilizer, and seeds, which equals 1.1 ounce to 1.4 ounce per square foot or 110 ounces per three hundred square feet. The individual straws will average one and half inches in length and vary from three-quarters inch to two inches.
With little or no surface breaking of the soil, a lawn is readily established simply by laying out the mats according to the invention on the soil. The seeds and fertilizer are retained essentially on one side of the mat by the adhesive. Since the adhesive is water soluble, when it rains or the mat is artificially watered, the adhesive dissolves and the seeds and fertilizer are released and find their way into soil. The straw prevents the seeds from being blown away and inhibits the growth of weeds. Since the straw is biodegradable, it eventually becomes part of the soil.
While the invention has been described by reference to a specific, preferred embodiment thereof, it is to be understood that the scope of the invention, as defined by the appended claims, is also intended to include all modifications and variations which would be obvious to one of ordinary skill in the art.