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CS-382 UNITED STATES DEPARTMENT OF AGRICULTURE NATURAL RESOURCES CONSERVATION SERVICE

CONSTRUCTION SPECIFICATION CS-382 FENCING

TABLE OF CONTENTS 382.1 Scope Page 1 382.2 Materials Page 2 382.3 Installation Page 2 382.4 Construction Details Page 2 382.4.1 General Criteria for All Standard Post and Wire Fences Page 2 A. Wire Page 2 B. Line Posts Page 3 C. Brace Posts Page 3 D. Cross Braces Page 3 E. Prefabricated Metal Brace Panels Page 4 F. Bracing and Alignment Page 4 G. Gates Page 4 H. Cattle Guards Page 4 I. Anchoring Page 4 J. Stays Page 5 K. Fence Height Page 5 L. Wire Spacing to Allow Big Game Passage Page 5 M. Fence Marking for Visibility Page 5 382.4.2 Suspension Fence- 3,4,or 5 strand barbed or Barbless wire Page 6 382.4.3 Standard Barbed and Barbless Wire, 3,4, or 5 strand including standard letdown fence Page 7 382.4.4 Permanent Power Fences Page 8 382.4.5 Woven Wire Fences Page 10 382.4.6 Buck and Pole and Combination Fences Page 11 382.4.7 Portable/Temporary Power Fence Page 11 382.4.8 Special Fences Page 12 382.1 SCOPE

The work shall consist of furnishing and installation of the fencing at the locations as shown on the conservation plan map. Types of fences covered by this standard are:

Standard barbed wire fence Woven wire fence Suspension fence Let-down fence Pole and Timber Fences Permanent Power Fences Portable/Temporary Power Fences

USDA-NRCS-UT 1/12 Aug 2010 CS-382 382.2 MATERIALS

The wire, posts, fasteners and all other materials shall be new and of a quality that is commonly used for ranch fences. Some used materials are permissible. Any used materials will be approved by the NRCS planner or technician prior to installation. They will be sound, of suitable strength for their intended purpose, free from excessive wear or decay, and able to last for at least 20 years. Used pipe such as ‘drill stem’ pipe and used railroad ties or telephone poles may be used as posts if they are whole, sound, free from decay, have not been previously used as fence material, and so long as minimum diameter and length requirements are met for the type of fence to be constructed.

382.3 INSTALLATION

The fence shall be installed as detailed on the drawings and maps.

382.4 ITEMS OF WORK AND CONSTRUCTION DETAILS

Special fence designs may be needed for game farms, wildlife migration routes, areas where access by people must be controlled, or other special situations. Such designs will be developed on a case-by-case basis submitted to the State Resource Conservationist for approval.

382.4.1 General Criteria for all Standard Post and Wire Fences

Specifications for standard post and wire fences include all barbed wire, woven wire, suspension, let down fences, and permanent power fences up to 60 inches tall. Drawings will be included as part of the specification.

Material and Installation Requirements

A. Wire Barbed wire shall be new, either zinc or aluminum coated with a minimum double strand strength of 950 pounds. Conventional barbed or smooth wire will be 13½ gauge or larger. High-tensile barbed wire will be 15 ½ gauge or larger. High-tensile smooth single strand will be 12½ gauge or larger. All wire shall be malleable enough so that proper splices can be made without damage to wire or coating. Woven wire shall be at least 11-gauge or larger top and bottom strands, 14-1/2-gauge or larger intermediate and vertical strands, and vertical strands spaced not more than 8 inches apart. All wire shall be new galvanized material.

Wire staples shall be serrated and a minimum of 1½ inches in length except for use in hardwood (such as oak) where ¾ inch can be used. The minimum diameter of staples shall USDA-NRCS-UT 2/12 Aug 2010 CS-382 be 9 gauge. Staples shall not be galvanized. Staples shall be driven diagonally with the wood grain in wood posts.

Wire clips or fasteners for steel posts or serrated staples made for particular style steel posts recommended by the post manufacturer may be used. For grooved steel posts, serrated staples will be driven into the groove according to the manufacturer’s recommendations. Space shall be left between the staple and post to permit movement of the wire.

B. Line Posts

All wooden line posts except pitch pine, juniper, red cedar & Osage orange shall, as a minimum, be treated with preservative such that complete penetration of the sapwood shall be obtained. Treatment shall extend up the post a minimum of the burial depth in the soil specified for the type of fence being constructed. Wooden line posts shall be a minimum of 4 inches nominal diameter inside the bark. All steel T-posts shall have a minimum weight of 1.33 pounds per foot of length exclusive of anchor plate. They shall have suitable means for supporting fencing such as studs, grooves, etc. Posts with lugs or lips, which are stamped out of the post itself, shall not be used. All steel posts shall have a suitable anchor plate securely fastened near the bottom. Length of line posts shall be as needed, for height of fence plus depth in soil. For other criteria for line posts, see specific additional criteria.

C. Brace Posts

Steel brace posts shall weigh a minimum of 2.84 pounds per foot of length. Attachment of cross braces to steel brace posts will be welded. They should be galvanized or painted with heavy tar. Wooden brace posts shall be treated with preservative as line posts. Wooden brace posts shall be a minimum nominal diameter of 6 inches inside the bark. Railroad ties or telephone poles that are whole, sound, free from decay, and have not previously been used as fencing material may be used, so long as minimum diameter and length requirements are met for the type of fence to be constructed. Length of brace posts shall be as needed for height of fence plus depth in soil. Maximum spacing between brace posts shall be 10 feet.

D. Cross Braces Cross braces may be constructed of wood material of 3 ¾ inch minimum diameter or steel pipe of 2 ½ inch minimum outside diameter. Wooden cross braces will be attached to wooden posts with 6 inch ring shanks or equivalent. Jacklegs are not applicable for cross braces.

E. Prefabricated Metal Brace Panels Metal brace panels used with steel posts shall only be used in situations where conditions prohibit the construction of a standard type of brace. Metal brace panels must be installed with 2 steel posts driven at least 2 feet deep back to back on each end of each panel. Metal USDA-NRCS-UT 3/12 Aug 2010 CS-382 brace panels must attach solidly to posts with an integral tube completely surrounding the post or with 11 gauge double strand smooth wire wrapped tightly around the brace panel and posts in 3 equidistant points. The maximum length of pull between braces constructed with prefabricated metal brace panels is forty rods.

F. Bracing and Alignment Bracing is required at all corners, gates, direction change angles, and abrupt vertical angle changes in the fence. In addition, line bracing is required at intervals to facilitate wire stretching. Maximum distance between braces in the fence line shall not exceed eighty (80) rods on level terrain and shall be installed at lesser intervals wherever horizontal direction of the fence changes or where vertical angles cause excessive strain on fasteners and posts. Bracing shall be designed to provide solid anchorage for wire stretching. All corner and direction change braces shall be braced in both directions of the fence. For standard 2, 3 or 5 post “H” braces, tension members will be incorporated in all brace panels. These will be comprised of four (4) complete loops of number eleven (11) gauge smooth wire or its equivalent cross sectional area in heavier gauge wire, either smooth or barbed. This tension member wire shall extend from a point approximately equal to the top wire of the fence, but at least one inch below the top of the brace post, to 3 to 6 inches from ground level of the post being braced. This tension member shall be twisted to provide needed rigidity. All standard “H” brace panels shall as a minimum maintain a two to one ratio of brace length to height of the top wire.

G. Gates The number of gates will be minimized to provide the necessary functions of the fence. Wire gates shall conform to the kinds, grades, and sizes of wire specified for new fence and shall include the necessary fittings, dancers and stays. Wooden gates shall be constructed of 2 inch or larger dimensional lumber, or 3 inch or larger poles. Commercial gates shall be of durable material and installed in accordance with the manufacturer’s recommendations. Fabricated metal gates shall be constructed of material of a quality equivalent to and with a life expectancy of the rest of fencing material.

H. Cattle Guards Commercial cattle guards shall be installed in compliance and cooperation with state or local Department of Transportation or Road Departments. They shall be installed to allow ingress/egress of expected vehicle and equipment that has right of way to utilize the road. Excavations, concrete, and other installation requirements will be according to manufacturers recommendations and applicable local laws, ordinances, and codes.

I. Anchoring In crossing narrow drainage ways, draws, or other low spots along the fence, a weight or deadman anchor equivalent to a 12 inch X 12 inch X 12 inch concrete block shall be fastened to the fence wires by vertical suspension wire or wires. This will be done in a manner that will result in maintaining wire spacing and clearances approximately the same as that of the rest of the fence.

J. Stays See specific additional criteria for the type of fence being built.

USDA-NRCS-UT 4/12 Aug 2010 CS-382 In areas where deer, elk and antelope are a consideration at least one stay will be placed between posts that are greater than 10 feet apart.

K. Fence Height The top wire shall be no less than 3 inches below the top of brace posts and at least 1 inch below the top of line posts. The specifications contained here are for fences up to 60 inches tall.

L. Wire Spacing to allow Big Game Passage For standard barbed wire fences (measured from the ground) Maximum height of 42” Minimum spacing of 10” between top 2 wires, 12” preferred

3 wire: 18”, 28”, 42” 4 wire Cattle Fence: 16”, 23”, 30”, 42” 4 wire Sheep Fence: 10”, 17”, 24”, 32”

In pronghorn antelope country, always allow 12 inches between the top wire and the next lower one, keep the total fence height as low as feasible (38” maximum) to allow ease of crossing by wildlife. The bottom wire must be smooth and a minimum of 16 inches off the ground.

M. Fence marking for visibility Where necessary for the safety of livestock, wildlife or people, the top wire and a mid- section wire nearest to center shall be marked by hanging a 3 inch section of vinyl undersill trim (a commonly used construction material for vinyl siding). Markers will be spaced 4 feet apart and staggered between the top and center row. Both light and dark colors will be used to ensure visibility during all seasons.

USDA-NRCS-UT 5/12 Aug 2010 CS-382 382.4.2 Additional Criteria Applicable For 3, 4, or 5 strand barbed or barbless wire Suspension Fence including Suspension letdown.

Suspension letdown fences shall be designed and constructed according to the publication Fences, July, 1988, 2400-Range.

A. Wire Only high tensile barbed or smooth wire (as specified in general criteria) will be used for suspension fences.

B. Line Posts Posts shall conform to the general criteria for line posts as described on page 2.

Depth in Soil: Depth of line posts in medium to heavy textured soils shall be a minimum of 24 inches except for steel posts, which shall be a minimum of 18 inches. Depth of line posts in sandy textured soils shall be a minimum of 30 inches except for steel posts, which shall be a minimum of 24 inches.

Maximum Spacing: Maximum spacing between line posts on high tensile wire suspension fences is 80 feet.

C. Brace Posts

Diameter: Regular wood posts shall be a minimum nominal diameter of 7 inches inside the bark. Posts shall conform to the general criteria for brace posts.

Depth in Soil: Depth of brace posts in soils shall be a minimum of 36 inches.

D. Bracing Only 3 post, gate, inline and end braces and 5 post corner braces shall be used to construct suspension fences. No 2 post braces shall be used.

E. Stays Wire stays for shall be of wire especially fabricated for this purpose and swing free of the ground to permit the fence to sway when contacted by animals. Wood stays used for letdown fence shall be durable and a minimum of 2 inches in diameter. Maximum spacing for stays shall be 20 feet.

F. Wire Tension Wire tension for all wires in suspension fences will be no less than 175 pounds per wire. It is desirable to use ratchet strainer devices on each wire to maintain correct tension.

USDA-NRCS-UT 6/12 Aug 2010 CS-382

382.4.3 Additional Criteria Applicable For 3, 4, or 5 strands barbed or barbless Standard Fence including Standard letdown. Letdown fences shall be designed and constructed according to USDA-NRCS standard drawings or according to the publication Fences, July, 1988, 2400-Range

A. Line Posts Posts shall conform to the general criteria for line posts as described on page 2.

Depth in Soil: Depth of line posts in medium to heavy textured soils shall be a minimum of 24 inches except for steel posts, which shall be a minimum of 18 inches. Depth of line posts in sandy textured soils shall be a minimum of 30 inches except for steel posts, which shall be a minimum of 24 inches.

Maximum Spacing: Maximum spacing between line posts shall be 16 ½ feet.

B. Brace Posts Posts shall conform to the general criteria for brace posts.

Depth in soil: Depth of posts in soils shall be a minimum of 30 inches.

C. Stays Wire stays shall be of wire especially fabricated for this purpose and swing free of the ground to permit the fence to sway when contacted by animals. Wood stays used for letdown fences (dancers) shall be durable and a minimum of two inches in diameter. Spacing for stays shall be at least one between each line post.

Notes on let-down fence designs in publication Fences, July, 1988, 2400-Range: Do not follow the drawings on page 157 for placing the wire on the dancer so that it rests on the ground with the dancer resting on top of the wire. Place the wire so that the dancer rests on the ground with the wire on top of the dancer. Staples should be left just barely loose enough to allow the wire to move inside of it. The Staple Let-Down Fence described on page 158 shall not be used.

D. Jacklegs Jacklegs for standard fence shall be designed and constructed according to USDA standard drawings or according to the publication Fences, July, 1988, 2400-Range as needed for site condition and fence duty. They should supplement, not replace fence braces where needed.

USDA-NRCS-UT 7/12 Aug 2010 CS-382 382.4.4 Additional Criteria Applicable For Permanent Power Fence

Letdown fences shall be designed and constructed according to the USDA-NRCS publication Electric Fencing for Serious Graziers, 2005.

A. Wire Only high tensile smooth wire will be used for permanent power fences, as specified in general criteria for wire. Any connections made to the electrified wire shall be made of steel. Other types of metal shall not be used.

Wire Spacing: In cases where the movement of antelope is a concern, the bottom wire of power fences shall be a smooth ground wire with subsequent wires being alternately charged, and the bottom wire will be at least 16 inches from the ground. Wires should be attached to line posts so that they ‘float’, or may be easily pulled in either direction past the post. Some suggested wire spacing for power fences is as follows: (“+” equals hot wire and “-” equals ground wire).

For cattle only: 2 wire = 28(-), 32(+) 3 wire =16(+), 26(-), 38(+) 4 wire = 10(-), 20(+), 30(-), 42(+) or 8(-), 18(+), 28(-), 40(+) or 16(-), 24(+), 32(-) 44(+)

For sheep and goats only: 4 wire = 10(-), 16(+), 24(-), 32(+).

For cattle & sheep: 5 wire = 10(+), 16(-), 24(+), 32(-), 44(+)

Wire Spacing to allow Big Game Passage: 2 wire = 20(-), 30(+) Contains cattle; passes deer, elk, moose 3 wire =22(-), 32(+), 42(+) Contains cattle or bison; passes deer, elk, pronghorn, moose 4 wire = 22(-), 32(+), 42(+), 52(+) Contains cattle or bison; passes deer, pronghorn

B. Line Posts

Type: In addition to line post types listed in general criteria (with appropriate UV resistant insulators), fiberglass posts made of a composite of marble, fiberglass, and polymer resins which have been treated by thermosetting, or extremely dense hardwood posts that are self insulating may be used.

Posts shall conform to the general criteria for line posts. In addition, fiberglass posts may be “T”-shaped with a minimum of 1¼ X 1¼ inches cross section with notches on 2 inch

USDA-NRCS-UT 8/12 Aug 2010 CS-382 spacing or round posts with a minimum diameter of ¾ inch. Self-insulating hardwood posts shall be a minimum of 1½ X 1½ inches cross section.

Depth in soil: Depth of line posts in medium to heavy textured soils shall be a minimum of 24 inches except for steel or fiberglass posts, which shall be a minimum of 18 inches. Depth of line posts in sandy textured soils shall be a minimum of 30 inches except for steel or fiberglass posts, which shall be a minimum of 24 inches.

Maximum Spacing: Maximum spacing between line posts shall be 40 feet.

C. Brace Posts Only 3 post, gate, inline and end braces and 5 post corner braces shall be used to construct suspension fences. No 2 post braces shall be used.

Diameter: Wood posts shall be a minimum nominal diameter of 7 inches inside the bark. Posts shall conform to the general criteria for brace posts on page 2.

Depth in soil: Depth of posts in soils shall be a minimum of 36 inches.

D. Jacklegs Jacklegs shall be designed and constructed according to USDA standard drawings or according to the publication FENCES, July, 1988, 2400 Range as needed for site condition and fence duty. They should supplement, not replace fence braces where needed.

E. Grounding All power fences must be well grounded. Energizer ground wire(s) must be connected to a copper or galvanized pipe or rod, driven into the ground a minimum of 6 feet. If soil depth prohibits this depth, use two or more galvanized pipes or rods. Ground wires in the fence must also be grounded to a galvanized steel pipe or rod. The ground wire attached to the fence may be located anywhere along the fence that a 6 foot depth can be obtained for the galvanized steel rod or pipe. Galvanized steel pipe at least ¾ inch or larger in diameter or ½ inch or larger diameter rod will be used for grounding.

F. Energizers Electronic energizers shall meet the following minimum requirements. A joule rating to deliver a minimum 1,000 volt shock for cattle, 2,000 volt shock for sheep, or 2,500 volt shock for big game, dogs, and coyotes at the farthest point from the energizer. Pulse time duration shall not exceed 0.3 milliseconds. Provisions for breaking the current (switch) will be provided in the design. Energizers will include solid state circuitry, high impact weather resistant case, safety pace fuse, and lightning arrester. Maximum length of wire shall not exceed the manufacturer’s recommendation for the size and type of wire and controller used.

USDA-NRCS-UT 9/12 Aug 2010 CS-382 G. Insulators Porcelain ceramic, plastic, or equivalent insulators will be used in power fences to attach wires to metal or wood posts. Insulators will be UV resistant material. All wires shall be insulated to permit switching of hot wires to ground wires and vice versa by switching the power connection and grounding rods.

H. Wire Tension Wire tension for all wires in power fences will be no less than 175 pounds per wire. It is desirable to use ratchet strainer devices on each wire to maintain correct tension.

I. Wire Splicing All splices will be made with press on sleeves or equivalent line clamps or line taps according to manufacturer recommendations. 382.4.5 Additional Criteria Applicable for Woven Wire Fence with 1, 2, or 3 strands of barbed or barbless wire above the woven wire.

A. Wire Woven wire shall, as a minimum, have a top and bottom wire diameter of 11 gauge, a minimum of 7 intermediate wires with a diameter of 14½ gauge and vertical stays a maximum of 8 inches apart also with a diameter of 14½ gauge. All woven wire shall be new and zinc or aluminum coated.

B. Line Posts Posts shall conform to the general criteria for line posts on page 2.

Depth in soil: Depth of line posts in medium to heavy textured soils shall be a minimum of 24 inches except for steel posts, which shall be a minimum of 18 inches. Depth of line posts in sandy textured soils shall be a minimum of 30 inches except for steel posts, which shall be a minimum of 24 inches.

Maximum spacing: Maximum spacing between line posts shall be 16 feet.

C. Brace Posts Posts shall conform to the general criteria for brace posts on page 2. Depth of posts in soils shall be a minimum of 30 inches.

D. Jacklegs Jacklegs shall be designed and constructed according to NRCS standard drawings or the publication Fences, July, 1988, 2400- Range as needed for site condition and fence duty. They should supplement, not replace fence braces where needed.

USDA-NRCS-UT 10/12 Aug 2010 CS-382 382.4.6 Additional Criteria Applicable for Buck and Pole Fence or a combination of poles and barbed or barbless wire. Bucks shall be formed by mortising and spiking two posts such that they form a cross having an interior angle from 60 to 80 degrees between the legs. The mortise point shall be approximately 12 to 16 inches from the top of the post. Bucks shall be held in an upright position by two diagonal poles spiked to the legs on one side of the fence. All bucklegs shall be firmly seated in the ground or anchored with rock placed to prevent movement. Barriers between bucks may consist of three or four horizontal poles spiked to the opposite legs from the diagonal brace poles. Wire may be used in lieu of poles. If wire is used, it shall be stapled to the legs at distances above the ground as set forth for wire fences. A minimum of three wires shall be used. If big game passage is a consideration, wire or pole spacing shall be 16,” 24” and 38”; and the top barrier shall be pole, not a wire.

Buck and Pole designs from other USDA agencies or from the publication Fences, July, 1988, publication 2400-Range may be used, as approved by the responsible technician.

A. Line Posts

Size: 5 inches nominal diameter inside the bark.

Maximum Spacing: Maximum spacing between line posts shall be 20 feet.

B. Poles

Size: Minimum of 3 inches nominal diameter inside the bark.

382.4.7 Additional Criteria Applicable for Portable/Temporary Power Fence one or two poly wires or tapes and temporary type posts.

A. Wire Wire will be made of UV resistant poly type material manufactured for use in electric fences or 1/16” steel cable. Size, number, spacing and type of wire will conform to manufacturer’s recommendations for animals, length of fence, and other factors. Poly wire will be at least 6 strand with stainless steel conductors with a resistance of no more than 9,700 ohms per mile.

B. Line Posts

Type: Posts for portable/temporary fence should be manufactured for that purpose from UV resistant materials. Plastic posts should have small diameter metal spikes and wide tread

USDA-NRCS-UT 11/12 Aug 2010 CS-382 plates for ease of movement and re-installation. Fiberglass rods may be used as posts as well. Wheel type line posts manufactured for that purpose are also acceptable.

Maximum Spacing: Spacing between line posts will be a maximum of 30 feet.

C. Brace Posts An anchor must be provided on either end of a section of portable/temporary electric fence and at each corner, gate, and angle in the fence. Posts in existing permanent fences may be used. If anchors need to be created, a single post that meets the General Criteria for line posts will be used.

D. Insulators, Grounding, and Energizers Insulators for anchor posts and energizer requirements will be the same as Permanent Power Fence. Grounding will be done according to manufacturer’s recommendations for the energizer used. Temporary / portable electric fence designs from Electric Fencing for Serious Graziers (USDA NRCS, found in the eFOTG) may be used, as approved by the responsible technician.

382.4.8 Special Fences

Additional designs for any special fences not included in these specifications may be designed on a case by case basis and approved by the State Resource Conservationist.

USDA-NRCS-UT 12/12 Aug 2010

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