The cranberry traps that attracted more than helpers

A signal added to the field

A cranberry experiment published in 2020 tested methyl salicylate, a volatile associated with plant responses to herbivores. Researchers compared baited and unbaited colored sticky traps in five cranberry beds. Crossing scent with color allowed them to ask whether an insect’s response to one signal depended on the other. Rodriguez-Saona and colleagues (2020).

Different insects answered differently

The lure increased predator captures, particularly hoverflies, and hoverfly responses depended on trap color. Parasitoid captures responded to color but not to the lure. Plant-feeding thrips were also attracted by the scent. An intervention intended to recruit natural enemies therefore affected several parts of the insect community rather than selectively summoning beneficial species. Rodriguez-Saona and colleagues (2020).

A trap count is not a harvest result

The experiment measured attraction and capture. It did not show that the extra predators killed enough pests to improve cranberry yields, nor that attracted thrips caused additional crop damage. Attraction was only one step between modifying a field and changing its pest pressure. Rodriguez-Saona and colleagues (2020).

A later experiment measured berries as well as visits

A separate study published in the February 2026 journal issue followed fifty cranberry beds on three New Jersey farms in 2022 and 2023. Researchers used baited and unbaited traps and cages, sampled pollinators, and measured berry number, volume and mass. Methyl salicylate increased pollinator captures and yield measures, extending the earlier trap experiment to outcomes used as proxies for pollination service. Ben-Zvi and colleagues, floral volatile and pollination (2026).

The response varied with cultivar and landscape. Waterbody patches at the broadest analyzed scale were associated with stronger benefits, while greater edge length reduced them. These contextual associations were not randomized changes to the surrounding landscape. The newer findings therefore address an unanswered harvest question without retroactively making the 2020 trap study a yield experiment or proving identical results on every farm. Ben-Zvi and colleagues, floral volatile and pollination (2026).