NZLA Etho – Lawn Herbicide

NZLA Etho — Selective Pre- & Post-Emergent Herbicide for Tall Fescue & Perennial Rye Lawns

NZLA Etho is a selective herbicide designed for Tall Fescue and Perennial Rye lawns. It provides both pre-emergent and post-emergent weed control when used properly. Only lawns consisting of pure Tall Fescue or pure Perennial Rye should be treated—do not use on Fine Fescue, as it can kill the lawn.

• Application rate: 40 mL per 100 m² in 4–5 L of water
• Pre-emergent use: follow with 3–5 mm of irrigation to push the product into the soil
• Post-emergent use: allow the spray to dry on the grass

Because Etho acts both through uptake by emerging weed shoots and by roots, it can suppress Annual Poa and Summer Grass, among other weed grasses and broadleaves.

How It Works / Mechanism & Safe Use

• For pre-emergent control, Etho must be applied before weed seeds germinate. The product forms a barrier that inhibits the early development of roots and shoots of weed seedlings.
• For post-emergent action, Etho acts on young weed shoots or leaves before the weed becomes well established.
• It does not harm Perennial Rye or Tall Fescue when they are healthy and established, but Fine Fescue is very sensitive and will suffer damage—hence, Etho should never be used on Fine Fescue lawns.
• There is some potential “knock-back” stress on Tall Fescue under poor conditions, so it’s best to apply when your lawn is in a healthy, actively growing state.
• Avoid applying Etho too close in time to PGR (plant growth regulator) applications to reduce stress.

Pre-Emergent Use & Strategy

• Etho can be used at the time of seeding a new 100 % Perennial Rye or Tall Fescue lawn, before the seed germinates. It does not stop the seed from germinating but suppresses weed seed germination, such as Poa and other foreign grasses.
• After spraying at 40 mL / 100 m², irrigate 3–5 mm to incorporate it into the soil.
• You may submit Etho with NZLA Meso in tank mix to broaden the pre-emergent spectrum. If you are topdressing, apply Etho/Meso on top of the new layer.
• Pre-emergent applications can be repeated every 2–3 months under normal conditions; during late autumn when Poa is more aggressive, this can be shortened to 6–8 week intervals.
• Note: On Tall Fescue lawns, it’s best not to mix pre-emergent and post-emergent Etho + Meso in the same application to reduce stress risk.

Post-Emergent Use & Timing

• Use Etho as a post-emergent on 100 % Perennial Rye or 100 % Tall Fescue at 40 mL / 100 m² in 4–5 L water.
• Wait 4 weeks after seed germination before using Etho in Tall Fescue lawns. In Perennial Rye, some studies suggest that post-emergent use can occur earlier (as soon as two weeks after germination), once seedlings reach about 1 inch in height.
• Etho is active through uptake by emerging shoots of weed grasses and by roots of certain broadleaf weeds soon after they germinate.

Weeds Controlled / Target Spectrum

Etho is especially effective against:

• Annual Poa (Poa annua)
• Summer Grass
• Chickweed
• Cleavers
• Fumitory
• Redroot Sow
• Thistle
• Spurrey
• Wild Portulaca

While Etho helps with Poa and some weed grasses, it does not replace a fuller-spectrum lawn herbicide (e.g. Triumph Gold) in your weed-control program.

To combat Annual Poa in Rye & Tall Fescue lawns, the best approach is:

• Apply 40 mL / 100 m² in 4–5 L water
• Immediately irrigate 3–5 mm to initiate the pre-emergent effect
• After 14 days, apply a second spray (same rate) and allow the product to dry on the foliage (for post-emergent benefit)

Application Tips & Best Practices

• Use a spray dye (such as NZLA Indicate) in your tank so you can avoid overlaps or misses. Note: NZLA Indicate degrades under UV (breaks down in sunlight) and is used at low rate (8 mL per litre of spray).
• Keep pets and children off treated areas until fully dry — ideally 24 hours.
• Etho is exempt from ACVM regulation (because it’s a lawn product). It’s not to be used on food crops, feed, or areas that will be grazed. It’s approved under the HSNO Act (Approval Code HSR000826).
• Active ingredient: 500 g/L Ethofumesate (suspension concentrate).
• The soil half-life for ethofumesate ranges from 5 to 14 weeks, and residual activity can last 4 to 8 months depending on soil conditions.