Subsurface application of chemicals

• US 4,683,826 A
• Filed: 04/15/1985
• Issued: 08/04/1987
• Est. Priority Date: 03/09/1982
• Status: Expired due to Fees

• Current Assignee: Board of Regents of the University of Nebraska
• Original Assignee: Board of Regents of the University of Nebraska
• Inventors: Burnside, Orvin C., Wittmuss, Howard D., Solie, John B.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Lewis, Bradley M.
• Application Number:
  US06/723,914
• Time in Patent Office: 841 Days
• Field of Search: 47/1.7, 111/7, 111/6, 111/73, 111/80, 111/86
• US Class Current: 111/124
• CPC Class Codes: A01C 23/025 Continuous injection tools
• CPC Class Codes: A01M 17/002 Injection of toxic gases or fluids into the soil special arrangements for delivering fertilising liquids directly into the soil A01C23/02

Abstract

In the subsurface application of herbicides, a plurality of upwardly directed nozzles having one millimeter openings are pulled beneath the soil surface behind the trailing side of a sweep in parallel paths two to four centimeters apart while jets of herbicide are emitted so that moving soil passing over each jet receives ample herbicide properly spaced to control germinating weeds. The pressure of application and speed of movement forms treated bands having widths before diffusion of five millimeters of soil and liquid uniformly mixed to a depth of approximately eight centimeters over the treated area. The sweep operates at a depth up to eight centimeters and pesticide incorporation depends on such variables as soil density, soil moisture, spacing of nozzles and injection pressure. A uniform distribution of chemicals in bands near or completely to the surface of the soil is made possible with a one-pass operation, while the soil and plant residue on the surface remain substantially undisturbed.

Claims

1. A method comprising the steps of:

forcing a horizontally elongated implement having two trailing wings joined at a forward end with the trailing wings being at an angle to each other of between 60 degrees or greater and being spread no less than 51 centimeters from each other at their trailing ends horizontally through the soil in a first direction at a depth sufficient to break up the subsurface without inverting the surface and no deeper than eight centimeters;

injecting chemicals in a jet under pressure substantially vertically upwardly from a location adjacent to the rear of the subsurface implement at a number of locations spaced from each other horizontally between two and four centimeters in a second direction at an angle to the first direction;

the step of injecting includes the step of injecting through nozzles having narrow openings spaced approximately 2 to 4 centimeters from each other;

said step of forcing including the step of forcing a standard for the implement including a plate connected at its bottom end to the implement and adapted to be connected at its top end to a vehicle, the plate having a dimension transverse to the implement that is no more than 5 percent the distance apart of the trailing ends of the implement;

said step of forcing further including the step of moving the jets through a sufficient amount of soil at a pressure of application and speed of movement of the jet to form a treated layer of soil containing more than four gallons of chemicals for each acre in which the chemicals are incorporated and one gallon of said chemicals incorporated in soil for at least 67 cubic yards of soil; and

the step of injecting including the step of injecting under a pressure sufficient so that for a given porosity of soil and moisture content, enough fluid penetrates the soil from one nozzle to provide a volume of soil wet with the chemical to extend at least two inches high and 0.5 inches wide with a forward velocity of the implement of at least four miles per hour.

2. A method comprising the steps of:

forcing a horizontally elongated implement horizontally through the soil in a first direction at a depth sufficient to break up the subsurface soil without inverting the surface soil;

injecting chemicals vertically upwardly under a pressure of approximately 100 to 700 grams per square centimeter from a plurality of nozzles, each of which has a different opening with a diameter in the range of 0.25 to 1.00 millimeter, each of which is spaced apart from another a distance of between 1 and 30 centimeters in a second direction at an angle to the first direction and each of which is located adjacent to the rear of the subsurface implement whereby the chemicals reach substantially the surface at a number of locations spaced from each other horizontally to form a plurality of substantially parallel bands of treated soil;

the step of forcing including the step of forcing the implement through the soil with the nozzles at a depth of less than 8 centimeters from the surface of the soil but more than two centimeters; and

the step of injecting including the step of injecting chemicals at locations spaced from each other in the second direction, a sufficient distance and at a sufficient pressure to form bands having a width of between one millimeter and 10 millimeters spaced from each other a distance less than 30 millimeters.

3. The method of claim 2 further including the steps of:

determining the pressure of injection, depth and speed needed for uniform distribution by making a plurality of trial runs across different areas with a liquid containing a fluorescent tracer;

selecting the pressure, depth and speed based on the uniformity of the fluorescent tracer; and

injecting chemicals across the field using the selected pressure.

4. The method of claim 2 further including the step of injecting chemicals downwardly downwardly onto the surface of the soil.