Every time there is smoke in the air I will get asked about the impact on crops. Yes, smoke lowers the temperature, so most days with smoke in the air you’ll get fewer growing degree units. But if it happens to be a day when the temperature hit 86 degrees or warmer, you may end up with more heat units. The reason is that most growing degree units end at 86 degrees, so anything beyond doesn’t count in the calculations. Plus, the smoke often keeps the air temperature up at night, meaning it may end up giving you a bit more heat units. Either way, smoke usually doesn’t account for a high percentage of a growing season meaning it rarely would make a noticeable impact.