Milkweed beetles and a monarch logged as ozone forecast rises

July 27, 2026Flat to Rolling Plains

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— striking longhorn beetles with crimson legs — turned up twice on July 26. Their entire life cycle depends on a single plant: larvae tunnel through milkweed roots over winter, adults emerge in midsummer to feed on pollen and nectar, then lay eggs back at the stem base. Two records here suggests established milkweed patches with enough root mass to sustain a full generation.

A single was logged this month — another species wholly dependent on milkweed as a caterpillar. Milkweed has lost much of its footprint across these plains as agricultural and suburban edges have filled in, shrinking the plant resource both species require.

Ozone is at AQI 64 today, with tomorrow's forecast tipping into Unhealthy for Sensitive Groups. Ozone damage weakens milkweed tissue and reduces the nutritional quality caterpillars depend on — making air quality during peak breeding season a real constraint on how well these patches function.

Data from EPA AirNow and iNaturalist

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