Tell KiwiPest what you are growing or restoring, what you need to control and what is around the block. It lists every pesticide used in New Zealand for that job, ranked by its risk to groundwater, streams, bees, soil life, wildlife and people at your site, with the toxicity, withholding period, soil mobility (Kd) and half-life of each.
1Getting started
KiwiPest runs entirely in your browser. Open kiwipest/index.html from the KiwiScience site, or double-click Open KiwiPest.command, which starts the site's local server and opens the tool. Your situation is saved in the browser as you work, so closing the tab and coming back picks up where you left off. Nothing is sent anywhere.
The tool has five tabs:
- Situation — the block, the problem and the surroundings.
- Options — the ranked shortlist for that situation.
- Database — every active ingredient, filterable and sortable.
- Compare — up to eight actives side by side, with a leaching chart.
- Spray plan — the season's applications, harvest dates and a CSV spray record.
2Describe the situation
What and where
Choose the land use — from dairy pasture and maize through pipfruit, kiwifruit and vineyards to plantation forestry, wetlands and native restoration — and the problem to control. The number after each problem is how many actives in the database are used for it in that land use. Pick the application method; it changes the drift, bee, bird and soil exposure. Baits, seed treatments, granules and fumigants keep their own delivery regardless.
If you enter the days until harvest or grazing, any active whose indicative withholding period is longer is set aside.
Soil and groundwater
Choosing a soil fills in typical organic carbon, bulk density, water content and macropore bypass. Replace the organic carbon with your soil-test value if you have one — it sets the Kd of every active (Kd = Koc × OC/100). Enter the mean soil temperature (it slows degradation in cooler districts), depth to groundwater and annual drainage.
Regional councils publish groundwater depth maps, and S-map and KiwiMap give soil order, organic carbon and drainage class for most of the country.
Water, weather, surroundings
The distance to the nearest water body is your buffer: drift and runoff both fall steeply with distance. Tick the boxes that apply — mole or tile drains, a nearby drinking-water bore, rain forecast, foraging bees, a sensitive waterway, native bush, dogs, public access, grazing stock. Each raises the weight on the matching risk or adds a check.
Constraints and priorities
Tick certified organic to keep only organically permitted inputs, and export produce to flag actives not approved in the EU. List the mode-of-action groups you have already used this season (e.g. 11, 3) to be warned about repeats. The six sliders set how much each risk counts; at 0 a risk is ignored.
3Read the options
The Options tab starts with the non-chemical and biological options for your problem, then lists the actives in order of their risk index (0–100, lower is better). For each:
- the six component scores (GW groundwater, SW surface water, bees, soil, wildlife, people) on a 0–100 scale, tinted green to red;
- the site Kd and half-life, and the GUS leaching score;
- the indicative withholding period;
- flag counts — ⚠ a limit (a serious concern at this site) and ! a caution — and the NZ status if it is anything other than approved.
The index measures risk, not whether the active works. Two options a few points apart are effectively equal. Always confirm on the label that a product is registered for your crop and pest.
Options set aside by your constraints (revoked approvals, organic, withholding period) are counted below the table; "Show them" lists them with the reason.
4The detail view
Click any row to open the full record: example NZ products, the key stewardship point, every property with its hazard class, and the calculation at your site — Kd, half-life at your temperature, travel time and the fraction reaching groundwater, spray drift, water concentration, bee hazard quotient and soil concentration — then the withholding periods, every flag, and the land uses and targets listed for it. From here you can add it to the comparison or the spray plan.
5Search the database
The Database tab holds all the actives, including those not relevant to the current situation. Search by name, chemical class, trade name or group code; filter by type, land use, target, status or organic; click a column heading to sort (click again to reverse). The Kd and site DT50 columns follow the soil and temperature on the Situation tab. Export CSV writes the filtered rows with every property for use in a spreadsheet.
6Compare actives
Add actives with + Compare on the Options tab, from the detail view, or from the list on the Compare tab (or take the top five options at once). The tab shows:
- a leaching chart of Koc against site half-life, with the GUS 1.8 and 2.8 boundaries. Actives up and to the left are mobile and persistent — the ones that turn up in groundwater;
- the risk profile: each component score as a bar, active by active;
- a side-by-side table of the assessment and every property.
7Plan and record sprays
Add applications from the Spray plan tab or the detail view, then fill in the date, block, product, rate (g active ingredient per hectare), area and method. KiwiPest works out the total active applied, the indicative safe harvest and grazing dates, and checks the season:
- a mode-of-action group used three or more times, or three times in a row;
- the cumulative copper load in kg Cu/ha.
Export spray record (CSV) produces a diary with the fields NZS 8409:2021 asks for. Add the water volume, weather and operator in the last column as you spray.
8Save, load and print
Save writes the whole situation — site, receptors, weights, comparison and plan — to a JSON file you can keep with the block records or send to an adviser. Load opens one. New clears everything. Print prints the open tab, or saves it as PDF.
9Three examples
Old man's beard in a riparian restoration planting
Land use: native ecosystem restoration · Problem: climbing and scrambling weeds · Method: cut-stump, frill or gel · Stream 5 m away, sensitive waterway ticked. The targeted method removes drift and most soil exposure, so every option scores low; glyphosate and dicamba carry no flags, picloram and aminopyralid are flagged for leaching, and metsulfuron for its toxicity to aquatic plants. The IPM note reminds you to cut vines at both ends and follow up seedlings for several years.
Leafroller in a kiwifruit orchard at flowering
Land use: kiwifruit · Problem: caterpillars · Airblast · Bees foraging ticked · days to harvest left blank. Bt, methoxyfenozide and tebufenozide come to the top; spinosad and the pyrethroids are flagged as highly toxic to bees; lambda-cyhalothrin is also flagged as disrupting biological control.
Pre-emergence weed control in maize on a Pumice soil
Land use: arable · Problem: annual broadleaf weeds · Pumice soil, groundwater 3 m, drainage 600 mm/yr, bore nearby. On this free-draining soil above a shallow aquifer most residual herbicides — including mesotrione and S-metolachlor — carry leaching limit flags, with atrazine and terbuthylazine at the bottom of the ranking. Short-lived or strongly sorbed actives (carfentrazone, glyphosate before planting, thifensulfuron) rank best: the comparison points toward post-emergence control rather than a persistent pre-emergence residual.
10Questions
- Is this a recommendation?
- No. It is a screening and teaching tool. The label, the EPA approval conditions, the MRL Food Notice and your regional plan govern use, and a trained (e.g. GROWSAFE-certified) applicator should apply any agrichemical.
- Why is a product I use missing?
- KiwiPest lists active ingredients, not products, and covers the actives most used in NZ land management. Search the Database tab by active name; products appear in the "Example NZ products" line only as examples.
- Why does the same active have different scores on two farms?
- Because the site matters: organic carbon sets Kd, temperature sets the half-life, depth and drainage set the leaching, and the buffer and slope set drift and runoff.
- The withholding period here differs from my label.
- Follow the label. KiwiPest's WHPs are indicative, often the shortest common one, and vary by product, crop and market.
- Does anything leave my machine?
- No. There is no backend, no analytics and no external request.
Think a number is wrong? Data sources & terms explains where the values come from; the record can be corrected in data/actives.js.