Remember when Reagan was mocked for saying trees pollute?

 

Small particle pollution caused by wild-fires in Canada.

"Trees cause pollution" is still mocked as "Gloriously stupid..." by Progressives.

Haze in New York City caused by wild-fires in Canada.

Mrs ERJ is driving to Detroit today. I will suggest that she run in A/C mode.

Peer reviewed literature

Peer reviewed literature suggests that the tree/pollution issue is very convoluted and there are many moving parts. A good, if long, paper HERE.

Trees emit isoprene and terpenes (ironically, "terpenes" are one of the "unique value propositions" for selling cannabis) which together with NOX (nitrogen oxides) are precursors to ground-level ozone.

The trees which emit the most isoprene and terpenes are also the ones that are best at sponging up and mitigating ground-level ozone.

A confusing image. Vertical axis is NOX availability. Horizontal axis is NMVOC availability. Label in black font is the position of Innsbrook, Austria. Label in green font is position of rural Georgia. The dotted line is a theoretical drive from the core-city to a rural area and the color gradient is the ozone level. Source

Urban areas have excess NOX and ozone formation is limited by the availability of NMVOC (Non-methane Volatile Organic Compounds). Rural areas have lots of NMVOC in the air (from the trees, naturally) and ozone formation is limited by the availability of NOX. The two come together in the suburbs on the downwind side of the urban heat-bubble where conditions are ideal for ozone formation: NOX-rich air is carried by the winds and encounters locally generated NMVOC from suburban trees.

Some trees produce less NMVOC than others. In some cases it is due to mutations.

The single most useful thing a suburb could do to mitigate ozone formation and retention would be to de-stress the trees by ensuring adequate soil moisture and fertilizer. Stressed trees emit more NMVOC and absorb less ozone.