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White phosphorus munitions, petrol bombs—all options were tried to no avail. Even the flamethrower was useless.

In addition to incendiary munitions, the British tried other things. For example, pesticides, strong acids, strong bases, or even chemical weapons. These weapons definitely wouldn't be considered humane normally speaking, but against insects, it was another story. Regrettably, those bugs weren't afraid of chemical weapons, and nothing changed with the spores.

Also, the British considered launching larger incendiary munitions, which could, in theory, burn all the air in the infected area, but the Finnish government wasn't happy. If the incendiary munitions got any bigger, the 50-meter isolation belt certainly wouldn't be effective. If there was a forest fire, then the loss would be severe!