Blue and Yellow Sticky Traps: Greenhouse and Field Use

What is a color trap and why does it work?

Many pest insects orient by color. A color trap takes advantage of that behavior: a brightly colored surface attracts certain insects and holds them. Sticky insect traps help reduce insect populations and make it possible to monitor infestation levels in crop areas. Those are their two functions, and it is worth telling them apart: one is control and the other is surveillance.

The monitoring function is usually the most valuable. A trap that is checked regularly tells you the pest has arrived before it is visible on the plant, and that gives you time to decide on a response calmly. The ICUSA agricultural sticky insect trap is offered in blue or yellow, with the same color on both sides.

Which insects does each color attract or repel?

The yellow color attracts insects such as whiteflies. Blue, on the other hand, repels insects of the aphid type. In the agronomic literature it is also common to use the blue trap to monitor thrips. Before buying for a specific pest, confirm with the advisor which color suits your crop, because the answer depends on the species you have.

How are they used in a greenhouse?

Inside a greenhouse the air is calmer and pests move less, so traps give a more faithful reading of what is happening. Some general practices:

• Hang them at foliage height or slightly above, and raise them as the crop grows.
• Place more traps near entrances, windows and areas where insects arrive, because that is where the pest shows up first.
• Check and record catches at a fixed frequency. What matters is the trend, not an isolated count.
• Combine them with a suitable cover. Among the greenhouse covers is the anti-virus film, which according to the ICUSA technical data sheet blocks a range of ultraviolet radiation that insects need for orientation.

In regions such as Jalisco, where berries and vegetables are grown under cover, trap monitoring helps decide when to intervene. To see how the protected structure is put together, see greenhouse and macro tunnel in Jalisco.

How are they used in open field?

In open field, wind, rain and dust change things. The sticky insect film is placed on stakes or posts, at crop height. Three points deserve attention:

• Placement along the edges. The pest enters the field from the border, so that is where it is detected first.
• Frequent replacement. Dust and large insects cover the surface and reduce its usefulness.
• Records by field. Note the date and the field so you can compare from one week to the next.

In Sinaloa, where whitefly and the viruses it transmits are a well-known concern in tomato, chili pepper and cucumber, early monitoring is part of crop management. If you also use mulch film in colors that reflect light, such as black/silver, the technical data sheet indicates that this color reflects light to reduce insect population dynamics and repel pests. See the details in agricultural mulch film in Sinaloa.

When does monitoring matter most?

It depends on the region. In Sinaloa, the fall and winter vegetable cycle starts in the middle of the hot season, which is when pressure from flying insects tends to be highest, so traps should be in place from transplanting, not once there is already damage. In Jalisco, where many fields are under cover almost year-round, monitoring is continuous and is stepped up when humidity and temperature rise inside the structure. In both cases the rule is the same: install before the pest appears and keep the record.

How many traps do I need and how often do I replace them?

There is no single number that works for every case. The quantity depends on the area, the crop, the pest pressure and whether the trap is used only for monitoring or also to reduce the population. In general, monitoring needs fewer traps than mass trapping, and replacement is done when the surface is saturated with insects, dust or dirt. The advisor or your field agronomist can define the right density for your property.

Are traps enough to control a pest?

No. A color trap is one tool within integrated management: field cleanliness, weed control, suitable covers and nets, constant monitoring and, if needed, other measures approved by your agronomist. Its great contribution is information: it tells you what is there, where and how much, and that keeps you from applying blindly. If catches rise from one week to the next, that is the signal to inspect the field and talk to your agronomist. If they stay low, you can space out interventions with more confidence.

Where can you get them?

The sticky insect trap can be quoted with an advisor, along with the rest of your plastics order. To compare regions, see the guide to agricultural plastics by state. If you are in Jalisco or Sinaloa, ICUSA serves you directly from its plant in Culiacán: write to us from the contact page.