Sticky Trap & Traps per Acre & Spacing
Catches whitefly
Enter area, traps per acre and the season length to get total traps, even spacing and replacements per season — for monitoring or mass-trapping flying pests.
Enter your field
Next: place 10 traps just above the canopy ~28.4 m apart, check/replace when full, and use them to time sprays at the economic threshold.
Rates are typical IPM guides; yellow attracts whitefly/aphids, blue attracts thrips — raise traps as the crop grows.
Sticky traps — key facts
- Total traps
- traps/acre × acres
- Monitoring
- ≈ 5 traps/acre
- Mass-trapping
- ≈ 50 traps/acre
- Spacing
- ≈ √(area ÷ traps)
- Yellow
- whitefly, aphids
- Blue
- thrips
- Height
- just above canopy
- Privacy
- Runs in your browser; nothing uploaded
A few traps to watch, many to trap
Sticky traps do two very different jobs depending on how many you hang. A handful per acre is a monitoring tool — it tells you which pests have arrived and whether numbers are climbing, so you can act before damage spreads. Scale up to dozens per acre and the traps themselves become control, physically pulling enough whitefly, aphids or thrips out of the air to slow an outbreak. Colour and height decide how well they work: yellow for whitefly and aphids, blue for thrips, always kept just above the canopy.
This tool turns your area and target density into the total traps to buy, traps per acre, even grid spacing and the replacements you'll need across the season. Use it to budget a monitoring programme or a mass-trapping push, and to time sprays from what the traps catch. Pair it with the Economic Threshold, Pheromone Trap and Biological Control Release tools for a full IPM plan.
Monitor or mass-trap
Pick a density for watching or trapping.
Even coverage
Grid spacing so no corner is missed.
Right colour
Yellow for whitefly, blue for thrips.
Plan replacements
Know how many refills the season needs.
Frequently Asked Questions
What do sticky traps do?+
Coloured sticky traps catch small flying pests — whitefly, aphids, thrips and leaf miner — on a glue-coated card. At low density they monitor pest pressure so you know when to act; at high density they mass-trap to physically reduce the population. They are a core, low-residue tool in integrated pest management (IPM) and work alongside biological and chemical control.
How many traps per acre do I need?+
It depends on the goal. For monitoring, around 5 traps per acre is enough to track which pests are present and how numbers are trending. For mass-trapping to suppress a pest, densities of about 50 traps per acre (and sometimes more in protected cultivation) are used. The tool multiplies traps per acre by your area for the total.
How is trap spacing worked out?+
Even spacing ≈ √(area ÷ number of traps). Convert your area to square metres, divide by the trap count and take the square root to get the metres between traps in a grid. So 50 traps spread over one acre (≈4047 m²) sit roughly 9 metres apart, giving even coverage rather than clustering traps in one corner.
Yellow or blue — which colour?+
Colour matters because pests are drawn to specific wavelengths. Yellow traps attract whitefly, aphids and leaf miner most strongly, while blue traps are best for thrips. Many growers run mostly yellow with some blue when thrips are the main threat. Use the colour that targets your dominant pest rather than a single colour for everything.
How high should the traps be?+
Place traps just above the crop canopy — roughly at the top of the plants — because that is where flying adults move, and raise them as the crop grows so they stay at canopy height. Traps left below the canopy catch far less. In rows, hang them on stakes or wires that can be lifted through the season.
How often must traps be replaced?+
Traps lose their catch as the glue fills with insects and dust, so they need replacing through the season — the tool estimates replacements from your season length and a typical service interval. Heavy pest pressure or dusty fields clog traps faster. Refreshing them on schedule keeps both monitoring counts and mass-trapping effective.
How do traps help me time sprays?+
Regular trap counts show when a pest crosses its economic threshold — the population at which the damage it will cause is worth the cost of treating. Spraying on trap-confirmed thresholds rather than the calendar avoids unnecessary applications, slows resistance and protects beneficial insects. See the Economic Threshold tool to set that trigger.
Can sticky traps alone control a pest?+
Monitoring traps don't control anything by themselves — they inform decisions. Mass-trapping at high density can meaningfully suppress some flying pests, especially in greenhouses, but it works best as one layer of IPM combined with biological control releases, resistant varieties, field sanitation and well-timed sprays when needed.
Are the figures exact?+
They're practical planning figures. The right density, colour and replacement interval vary with the crop, pest, climate and whether you are monitoring or mass-trapping, so treat the outputs as a starting plan and adjust from your own trap counts. Scouting the field regularly is what turns trap data into good decisions.