382G Fence-Rock and Straddle Jack Fence Posts

USDA NATURAL RESOURCES CONSERVATION SERVICE ARIZONA CONSERVATION PRACTICE SPECIFICATION FENCE (Feet) Rock, Figure-4, and Straddle Jack Posts Practice Code 382G

Client Date NRCS Field Office Conservation District NRCS Assistance By Project Name Field / Pasture Numbers Purpose of Fence Planned Length (ft) Kind of Animal

1. SCOPE during construction shall be safely collected and properly disposed of. Construct a barrier to animals or people. Old posts, wire, and other fence materials shall be 2. GENERAL SPECIFICATIONS completely removed from the site and properly disposed of. Straddle jack line posts can be used to cross short 3. ASSEMBLY sections where normal line posts cannot be installed. No more than 7 straddle jack line posts Straddle Jacks shall be set consecutively in a section of fence. To install straddle jacks (Figure 1), stretch the Figure-4 and rock jack line posts may used on fence wires to the anchor posts of the brace fence line sections with shallow, swampy, or assemblies for the fence section. Notch the expansive clay soils, or where line posts cannot straddle jack posts where they cross, and tie them be set in the ground due to underground utilities together with two wraps of 9 gauge or heavier or cultural resources. Rock jack line posts may be wire. Set the jack in place under the top fence spaced the same as standard fence line posts or wire and staple the top wire to one of the posts. may be used in combination with “T-posts”, Make the jack footing secure and wrap and tie the wooden posts or figure-4 posts. lower spread wire to each post. Any alterations or additions to this practice design A 50 pound or heavier rock shall be used to must be approved by NRCS prior to modifying this anchor the straddle jack. Make a sling around the specification. rock using 2 strands of 9 gauge or heavier smooth Fences installed on state, federal, and tribal wire. Support the rock on smaller stones. Twist owned lands normally require permit or approval. the sling wires up around the lower fence wires and secure to the jack where the posts cross. The NRCS assumes no responsibility for Then remove the smaller support stones from interference with private or public utilities. under the anchor. State and federally protected plants, animals, cultural resources, and historically significant properties shall not be harmed or destroyed during the installation of this practice. All work shall be done in a manner that minimizes soil and vegetation disturbance and the movement of sediment and other pollutants into streams and water bodies. Vegetation clearance shall not exceed 20 feet in width. Any engine oil, lubricants, or other chemical pollutants spilled

NRCS Field Office Technical Guide, Section IV Page 1 of 3 NRCS, Arizona April, 2008 382G – Fence-Rock and Straddle Jack Fence Posts Specification

Rock Jacks

Rock jacks shall be constructed and placed as shown in figures 3, 4, 5, and 6.

Figure 1 Figure-4 Posts

Figure-4 posts will be constructed as shown in figure 3.

Figure 3

Figure 2

Figure 4 NRCS Field Office Technical Guide, Section IV Page 2 of 3 NRCS, Arizona

April, 2008 382G – Fence-Rock and Straddle Jack Fence Posts Specification

5. OPERATION AND MAINTENANCE

The expected life span of this practice is 10 years. With good maintenance, fences installed to these specifications can last 20 years or more.

Typical maintenance required includes

 periodically checking fence wire tension  repairing any wire breaks that may occur

Figure 5 I have reviewed the plans and specifications. I accept and approve them for the installation of this project.

Landowner or Operator Date

Figure 6

4. MATERIALS

Wood used in the construction of straddle posts, figure-4 posts, and rock jacks shall have a minimum life expectancy of 10 years. Untreated juniper, oak, mesquite, black locust, and redwood posts may be used. Pine or other softwood must be treated with a preservative.

NRCS Field Office Technical Guide, Section IV Page 3 of 3 NRCS, Arizona

April, 2008