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Tree Fence Specifications - ASTM A-787 ASTM A-653 and ASTM A-607

Tree Fence Type - preferred

The 18” high ornamental iron fence w/top row of rings shall meet or exceed the following specifications: ASTM A-787, ASTM A-653, and ASTM A-607 (revised August 20, 2008).


  • Posts – above grade: 1” x 1” x 1/8” tubing, 18” in length
  • Posts – below grade:  ¾” solid steel bars, 18” in length
  • Top rail embellishment:  1” x 1/8” flat steel channel
  • Top rail:  2” molded steel bars
  • Mid rail:  1” x ½” x 1/8” steel channel punched to accept pickets
  • Bottom rail:  1” x ½” x 1/8” steel channel punched to accept pickets
  • Pickets:  ½” x ½” solid steel bars
  • O-Rings:  4 ½” tubing
  • Finish:  all materials are welded and primed with 1 coat of Red Oxide primer and 1 coat of Black Satin paint (Sumter Coating) mixed with primer

Fabrication and Installation

  1. Fence shall be 3-sided unless otherwise specified, open side facing the curb
  2. Top-to-mid rail spacing – 5.75” o.c.
  3. Mid-to-bottom rail spacing – 8” o.c.
  4. Bottom rail shall sit approx. 3” above grade surface
  5. Post-to-picket spacing – 5.25” o.c.
  6. Picket-to-picket spacing – 5” o.c.
  7. Space O-ring tubing according to picket and post locations; all O-rings shall be welded to adjacent pickets, posts, and rails
  8. Weld 1” x 1” x 0.125” post tubing at ends and corners and weld an additional post along the length at mid-point. If tree box length exceeds 12’, posts should be welded every 4’ along length
  9. To provide below grade support in concrete, weld ¾” solid steel bars to all 1” x 1” x 0.125” post tubing
  10. To deter seating, weld 1” x 0.125” flat steel channel to 2” top rail
  11. For existing tree boxes, openings must be measured prior to fabrication to ensure that fences will fit just inside the boxes and side panels must be fabricated with a setback of approx. 6” from back edge of existing curb to allow sufficient room for car doors to swing
  12. For new tree boxes installations, fence dimensions shall be standardized based on length and width of proposed openings (e.g. 4’ x 9’, 6’ x 10’, etc.), however, the setback for the side panels shall remain consistent at 6” from back edge of curb to allow sufficient room for car doors to swing
  13. Concrete footings shall be at minimum 10” wide by 24” deep and the concreting shall be performed in accordance with the manufacturer’s specifications


  • Strength: 3000 psi with a slump of 3
  • Air entrainment: 5% to 8%
  • Aggregate size: ¾” max.
  • Mortar compressive strength at 28 days: 32 MPa
  • Meets ASTM C 150, Type 1
  1. Finished concrete shall be two (2) inches below existing grade and pitched to direct water away from posts.
Tree Fence Model - preferred type
UFA Preferred Tree Fencing
Tree Fence Model - Close-upTree Fence Model (close-up)