Pheromone Trap Calculator & Traps, Spacing & Lures
Plans traps for monitoring
Plan your pheromone traps — from area and purpose get the number of traps, the spacing between them, the lures for the season and the cost.
Enter your field & trapping
Next: scout your trap catches each week and act on the economic threshold — when catches cross the action level for your pest, time your spray or release of biocontrols instead of spraying on a fixed calendar.
Monitoring ~4–5 traps/acre; mass trapping ~15–25/acre.
Pheromone traps — key facts
- Monitoring
- ≈ 4–5 traps/acre
- Mass trapping
- ≈ 15–25 traps/acre
- Spacing
- √(area ÷ traps)
- Lure life
- ≈ 2–6 weeks
- Place at
- crop canopy height
- Reusable
- trap body; lures recur
- Best with
- scouting + thresholds (IPM)
- Privacy
- Runs in your browser; nothing uploaded
Catch pests early, spray less
Pheromone traps are a cornerstone of integrated pest management — a few monitoring traps tell you exactly when a pest arrives and how its numbers build, so you spray on time instead of by the calendar; a denser grid for mass trapping can suppress the pest directly by capturing adults before they breed. Either way, the right number, spacing and lure schedule make the difference.
This tool turns your area and purpose into the traps needed, the spacing between them, the lures for the whole season and the cost, separating one-off trap bodies from recurring lures. Use the correct lure for your target pest, set traps at canopy height across the field, replace lures on schedule, and act on the catches. Pair it with the Economic Threshold and Spray & Tank Mix tools to decide and apply any sprays.
Right density
Monitoring vs mass-trapping traps for your whole field.
Even layout
The spacing tells you how to grid the traps across the crop.
Buy enough lures
Season-long lure count from the lure life — no mid-season gaps.
Budget it
Separate trap and lure costs for the season.
Frequently Asked Questions
How many pheromone traps per acre?+
For monitoring (detecting and timing pests), about 4–5 traps per acre is typical. For mass trapping (actually suppressing the pest population), you need many more — roughly 15–25 per acre. This tool multiplies your chosen density by the area to give the total traps and the spacing between them.
What is the difference between monitoring and mass trapping?+
Monitoring uses a few traps to detect when a pest arrives and how its numbers change, so you can time sprays to the economic threshold. Mass trapping uses a high density of traps to capture enough adults (usually males) to reduce mating and cut the next generation — a control method in itself.
How far apart should pheromone traps be?+
It depends on density: monitoring traps at 4–5/acre sit roughly 25–30 m apart, while mass-trapping at 20/acre is much closer (~14 m). The tool computes the approximate spacing from your traps per area so you can lay out an even grid across the field.
How often do I replace the lures?+
Lures lose their pheromone over time — commonly every 2–6 weeks (check the product). Over a season you'll change them several times: the tool divides the season length by the lure life to give the number of lure changes and the total lures needed, so you can buy enough.
Where should I place the traps?+
At the crop canopy height (raise them as the crop grows), spread evenly across the field including the borders where pests often enter first, and away from strong wind that disperses the plume. Keep traps clean and check them regularly — weekly for monitoring.
What pests do pheromone traps work for?+
Many moth and fly pests have species-specific lures — fruit flies, fruit and shoot borers, bollworm/Helicoverpa, diamondback moth, pink bollworm, tuta absoluta and more. Use the correct lure for your target pest; the trap design (delta, funnel, water/yellow sticky) is matched to the pest too.
Do pheromone traps replace spraying?+
Monitoring traps don't control pests — they tell you when to act. Mass trapping can reduce the need for sprays but usually works best as part of integrated pest management (IPM) alongside scouting, thresholds and selective sprays. They cut, rather than eliminate, the need for chemicals.
How many traps for mass trapping fruit flies?+
Fruit-fly mass trapping commonly uses around 15–25 traps per acre (some programmes more), with methyl eugenol or cue-lure plus a killing agent. Set the mass-trapping density in the tool and it gives the traps, spacing and lures for your orchard area.
Are pheromone traps cost-effective?+
Often yes — monitoring traps are cheap insurance that prevent wasted, mistimed sprays, and mass trapping can cut chemical and damage costs. Enter trap and lure prices to see the season cost; weigh it against the sprays and crop loss avoided (the Economic Threshold tool helps).
How long do traps last?+
The trap body is usually reusable for a season or more; only the lure (and sticky liner, if used) is replaced periodically. So your main recurring cost is lures. The tool separates traps (one-off) from lures (recurring) so you can budget both correctly.