The Importance of Excavator Teeth Selection When Digging Leachfields

When it comes to septic system installations, one of the most critical excavation tasks is digging the leachfield (also known as the drain field). While it might seem like a straightforward process—dig a trench and lay the pipe—the tools used can significantly affect the outcome. Among these tools, excavator teeth play a vital role in ensuring efficient, clean, and precise digging.

In this blog, we’ll dive into why the type of excavator teeth matters when digging leachfields, explore the different types of teeth available, and help you understand how choosing the right one can make or break your excavation job.

Why Excavator Teeth Matter in Leachfield Excavation

Leachfields require careful and clean trenching. The goal is to:

• Minimize soil disturbance

• Maintain proper trench dimensions

• Ensure level trench bottoms

• Avoid soil compaction

Using the wrong type of excavator teeth can result in:

• Over-excavation or uneven trench bottoms

• Soil smearing, especially in clay soils, which reduces drainage effectiveness

• Poor trench wall integrity, leading to cave-ins

• Increased wear on the excavator, slowing down the job

By using the right teeth, you improve both the efficiency and quality of your leachfield installation.

Common Types of Excavator Teeth (And When to Use Them)

There are various types of teeth designed for specific digging conditions. Here are the most common:

1. Standard Chisel Teeth (General Purpose Teeth)

• Shape: Tapered with a chisel point

• Best for: Soft to medium soils

• Pros:

  • Good penetration

  • Versatile and widely available

• Cons:

  • Wears faster in rocky or abrasive soils

For leachfields in loamy or sandy soils, chisel teeth offer efficient trenching without disturbing too much surrounding earth.

2. Tiger Teeth

• Shape: Sharp, pointed tip (like a tiger’s fang)

• Best for: Hard-packed soil, frozen ground, or compact clay

• Pros:

  • Excellent penetration

  • Breaks tough soils with ease

• Cons:

  • Can gouge or over-dig if not used carefully

  • Less ideal for creating smooth trench bottoms

Tiger teeth are useful when working in dense or clay-heavy soils that resist standard digging. However, they require an experienced operator to prevent over-excavation.

3. Twin Tiger Teeth

• Shape: Two sharp points side by side

• Best for: Very hard soils and light rock

• Pros:

  • Aggressive cutting action

  • Ideal for loosening compacted areas

• Cons:

  • Even more aggressive than single tiger teeth

  • Not recommended for fine grading

Use these only when absolutely necessary, and consider switching to chisel teeth for finishing passes.

4. Rock Teeth (Abrasion Teeth)

• Shape: Blunt, reinforced, often with wear-resistant materials

• Best for: Rocky soils, abrasive materials

• Pros:

  • Long wear life

  • Handles tough digging conditions

• Cons:

  • Poor at fine cutting or shaping

  • Can disturb trench shape

If your leachfield site has rocky or gravelly subsoil, rock teeth may be necessary—but follow up with smoother teeth if precision is required.

5. Flare or Wide Bucket Teeth

• Shape: Broad, flat end (like a spade)

• Best for: Loose soils, fine grading

• Pros:

  • Great for finishing trench bottoms

  • Smooth cuts and minimal soil disturbance

• Cons:

  • Not suitable for hard or compacted ground

These teeth are ideal for the final trench pass to ensure a flat and even trench bottom—key to even water distribution in the leachfield.

Tips for Choosing the Right Excavator Teeth for Leachfields

1. Know Your Soil Type: Test or inspect the soil before digging. Clay, sand, loam, and rocky soil each require different teeth.

2. Match Teeth to the Job Phase:

   • Use aggressive teeth (tiger/twin tiger) for breaking ground

   • Switch to chisel or flare teeth for cleanup and precision

3. Inspect and Maintain Teeth: Worn teeth reduce cutting efficiency and increase strain on your machine.

4. Avoid Over-Excavation: Aggressive teeth can quickly remove too much material. Depth control is key.

5. Consider Soil Smearing: In clay soils, sharp teeth can smear the trench wall or bottom, leading to drainage issues. Use less aggressive teeth or hand-finish if needed.

Conclusion

The type of excavator teeth you use when digging a leachfield may seem like a small detail—but in reality, it plays a critical role in the performance, longevity, and reliability of the entire septic system.

Whether you're a contractor or a DIY installer, understanding and using the right excavator teeth can save you time, money, and hassle down the line. Proper tooth selection leads to cleaner cuts, less soil compaction, and better drainage—all essential for a high-functioning leachfield.

Need Help Choosing the Right Teeth?

If you're unsure about which teeth to use for your soil type or machine, talk to your local equipment dealer or consult with a septic system professional. It’s a small investment that makes a big difference in your project's success.