Detailed pollen and mold reports for Houston Texas. Pollen and mold spore counts are made available Monday through Friday, except for City of Houston holidays.

Houston Texas Pollen and Mold Counts (September 27, 2024, to September 30, 2024)

Pollen:

• Houston Texas Tree Pollen: Skyrocketed from 26 to 297 (+271, +1,042%), with a massive increase in Ulmus (Elm).

• Houston Texas Grass Pollen: Increased from 10 to 36 (+26, +260%).

• Houston Texas Weed Pollen: Increased from 472 to 783 (+311, +66%), with a significant rise in Ambrosia (Ragweed) and other weed species.

Mold:

• Total Mold: Increased from 17,287 to 23,044 (+5,757, +33%), driven by significant rises in Cladosporium, Alternaria, and Epicoccum.

Detailed Changes:

Tree Pollen:

• Ulmus (Elm): Increased by 271 (from 26 to 297).

• All other tree species remained at 0.

Grass Pollen:

• Increased by 26 (from 10 to 36).

Weed Pollen:

• Ambrosia (Ragweed): Increased by 259 (from 470 to 729).

• Chenopodiaceae/Amaranthaceae (Amaranth): Increased by 24 (from 0 to 24).

• Other Weed: Increased by 30 (from 0 to 30).

• Cyperaceae (Sedge): Decreased to 0 (from 2).

Mold:

• Algae: Increased to 36 (from 8).

• Alternaria: Surged to 747 (from 26).

• Ascomycetes: Decreased to 3,730 (from 7,351).

• Basidiomycetes: Increased to 3,250 (from 2,734).

• Cercospora: Increased to 820 (from 296).

• Cladosporium: Increased significantly to 13,249 (from 5,407).

• Curvularia: Increased to 218 (from 73).

• Drechslera/Helminthosporium: Increased to 60 (from 36).

• Epicoccum: Surged to 127 (from 14).

• Nigrospora: Increased to 145 (from 24).

• Oidium/Erysiphe (Powdery Mildew): Appeared with a count of 18.

• Penicillium/Aspergillus: Decreased sharply to 291 (from 1,005).

• Periconia: Decreased to 18 (from 156).

• Pithomyces: Increased to 85 (from 8).

• Rust: Increased to 42 (from 6).

• Smuts/Myxomycete: Increased to 194 (from 119).

• Spegazinia: Decreased to 2 (from 6).

• Stemphyllium: Appeared with a count of 12.

• Tetraploa: Decreased to 0 (from 10).

• Torula: Decreased to 0 (from 8).

Summary:

• Houston Texas Pollen: The pollen count experienced a dramatic rise, with tree pollen (particularly Ulmus/Elm) seeing a massive increase, followed by significant gains in both Grass and Weed Pollen, especially Ambrosia (Ragweed).

• Houston Texas Mold: Mold counts also surged, with a notable increase in Cladosporium, Alternaria, and Epicoccum, though Ascomycetes and Penicillium/Aspergillus saw declines.