Alfalfa Plant Bug

Adelphocoris lineolatus · Order: Hemiptera · Family: Miridae

Also called: Lucerne Bug

Damages trees, gardens or crops. The alfalfa plant bug damages alfalfa and cotton crops.

Source: Wikipedia

Alfalfa Plant Bug
Photo: Gordon Johnston, CC BY-SA

The alfalfa plant bug (Adelphocoris lineolatus) belongs to the Miridae family and is also called the Lucerne bug. Adults and nymphs feed on alfalfa and cotton plants, and adults appear from late June to October.

Source: Wikipedia

How to recognize it

Adelphocoris lineolatus is known as the Lucerne bug or alfalfa plant bug and is in the Miridae family.

Source: Wikipedia

Where it lives

It prefers humid, cool environments and can be found in both dry and damp fields or grasslands.

Source: Wikipedia

What it eats

Both adults and nymphs eat the reproductive and vegetative parts of alfalfa and cotton plants.

Source: Wikipedia

Life cycle

Eggs develop in 8 to 12 days, with some overwintering, and the bug goes through five nymphal stages.

Source: Wikipedia

When you see it

Females start laying eggs at the end of July, and adults are seen from late June through October.

Source: Wikipedia

Lookalikes

It is also called the Lucerne bug or alfalfa plant bug and belongs to the Miridae family.

Source: Wikipedia

Where it is found in the US

Recorded in 38 of 51 states and DC. Most records: New York, Illinois, Wisconsin, Minnesota, Massachusetts, Pennsylvania, Michigan, Ohio.

Darker = more records. Counts are museum and citizen-science records, not population size.

Source: GBIF

Status: introduced in United States. Source: iNaturalist

Months it is reported in the US

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Source: GBIF

More photos

Questions people ask

Does the alfalfa plant bug damage crops?

Yes, it feeds on alfalfa and cotton, harming those crops.

Source: Wikipedia

When can I expect to see adult alfalfa plant bugs?

Adults are present from late June through October.

Source: Wikipedia

Same family (Miridae)

Sources

  • Wikipedia: https://en.wikipedia.org/wiki/Adelphocoris_lineolatus

Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia

Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

How this page works

This is one bug's fact sheet. The colored box at the top says whether it is dangerous. Sections below cover how to recognize it, whether it is a pest, and how to deal with it. The US map shows which states have records; tap a state to see other bugs there.

Every fact on Bug FAQ comes from a named source (university extension sites, government agencies, GBIF, iNaturalist, Wikipedia). The source is linked next to each section. If we have no source for something, we leave it out.