is this true?

[harris7]

The high power lights that the dopers use to grow the drugs generate a large amount of heat. The criminal farmer must vent this heat or the plants will get to hot. We can find the unusually hot exhaust pipe in the roof or the hot room in a house that seems to be hot and cold on a regular cycle (hot when the lights are on cold when they are off). taken from
http://www.predictive-maintenance.com/marijuana.html

and from http://www.predictive-maintenance.com/marijuana.html

spectral contrast between marijuana and other plant canopies appears most significant for green, red edge and short wave infrared wavelengths, however, isolation of marijuana canopy spectral signatures during land cover classification may be difficult using visible-near infrared systems

I don’t know why you are being so hostile. We agree