> ## Documentation Index
> Fetch the complete documentation index at: https://badixth-dc85e378.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Diagnose and Respond to Symphylids in Pineapple

> Identify symphylid damage in pineapple from patchy establishment and pruned root tips on replant blocks, and control with pre-plant soil fumigation, resistant soils, and organic amendments.

Symphylids (**Scutigerella immaculata** and related species) are small (2 to 8 mm) white centipede-like arthropods that live in the top 20 cm of soil. They feed on root tips of establishing pineapple plants, causing patchy stands and slow start-up on replant blocks. On heavily infested blocks whole planting rows fail.

**Regional priority:** High in Hawaii, Australia, and Latin America on replant blocks. Moderate elsewhere.

## When pineapple is most vulnerable

At **planting to establishment (months 0 to 3)**. Once the root system is established, symphylid damage is minor.

## How symphylids show in satellite data

* **Patchy establishment** shows as low, uneven NDVI in the first 3 months.
* Distinguish from drought and soil variability by soil sampling and direct symphylid counts.

## Field symptoms

* **Patchy, weak establishment** with rows of failed plants
* **Slow, stunted growth** on surviving plants
* **Root tips chewed off**, root system reduced to short stubs
* **White centipede-like arthropods** in the topsoil around the plant base - the diagnostic sighting
* **Best confirmed** by digging a soil sample in a plastic bag and warming it in the sun; symphylids move to the surface

## Reduce the damage by

* **Pre-plant soil sampling** on replant blocks to count symphylids before deciding.
* **Pre-plant soil fumigation** (metam sodium, 1,3-dichloropropene) on chronic blocks where regulations allow.
* **Long fallow with a non-host crop** (grass) reduces populations.
* **Green manure incorporation** (mucuna, sunn hemp) suppresses symphylids.
* **Deep plowing before planting** disrupts populations in the top 20 cm.
* **In-furrow insecticide** at planting (ethoprop, where registered) on known infested blocks. **Chlorpyrifos was withdrawn from agricultural use in Malaysia in 2023 and its registration ended on 1 July 2026** - see [Pesticide registration](/snippets/pesticide-registration).
* **Do not replant immediately** into a symphylid-heavy block - the establishment loss is permanent.

## Set an alert for early warning

<Tip>
  Turn the diagnosis into a trigger. Symphylids are a pre-plant decision, so schedule sampling and stand-count alerts.
</Tip>

Recommended settings for symphylids on pineapple:

* **Pre-replant sampling reminder** - schedule symphylid soil sampling 2 months before any planned replant.
* **Establishment stand-count alert** - flag any block with more than 15% gap count at 8 weeks after planting.
* **NDVI establishment alert** - trigger on any block with NDVI below 0.15 at 8 weeks after planting (BRIS and mineral upland).

## Related

* [Pineapple Diagnosis](/guides/Crop/Pineapple/pineapple-diagnosis)
* [Nematodes](/guides/Crop/Pineapple/biotic/diseases/nematodes) - overlapping root damage; separate by direct inspection.
* [Set up automated crop alerts](/guides/alerts-notifications)