I am looking for pictures of damages(in bracts) caused by a too high concentration of carbon dioxide;
> malfunction of gas heater <
Can anybody help ?

Don't faulty heaters actually give off carbon monoxide? There is a huge difference between carbon dioxide and carbon monoxide compounds. I have not personally seen the effects of high unburnt gas on Poinsettias but did one time have a heater where a spider web caused the flames in one burning plate to elongate and turn very yellow. This caused a black carbon soot to be disbursed in that greenhouse and the effect was very tiny black dots on the Poinsettia bracts which eventually caused tiny botrytis infections on the bracts. I have also witnessed the tiny botrytis dots on Poinsettia bracts when the heaters were working properly so in my opinion the tiny infected areas are not always heater related....Michael Pawelek

This message has been edited. Last edited by: Michael Pawelek,

Michael, sorry for confusion.

On one hand I am looking for pictures of damage through carbon monoxide(gasheater malfunction)

and on the other hand I search for pictures
of damages by CARBON DIOXIDE(no reference to any gas-heaters)