To be perfectly honest, I cannot say what the upcoming cold will do to the mushrooms. no one can really predict mother nature. After all, the weather is about the only thing that is beyond man's control.
Really, it all depends on where each mushroom is located and how much real exposure it will have to the cold and for how long. That last part is the key as I will get to in a bit. Many of you who have been finding them the last few days may have noticed that some have a reddish tinge. I think this is from exposure to the cold. Note that not all have it because some remain covered and are not exposed but then grow during the warmth the next day and push up through the leaves. I also found a few morels yesterday with blackened tops, which I also believe is due to freezing. These were usually large yellows (3-4 inches). What I imagined happened is that the tips of these were poking up at some time during a nice cold night and they got freezer burn so to speak. But the part under the leaves was protected continued to grow fine once things warmed up.
I think the real question on everyone's mind, is will this be like it was in 2007. For those who may not remember it, the morels came up much the same time they did this year, but a nasty cold spell came through the second weekend of April and froze everything that was up. I remember going out that infamous Saturday morning and finding beautiful morels that were frozen solid. I picked them and when they thawed they were limp and only good if your fried them immediately. Those left in the field fell over and became black and moldy, marking an early end to the season depending on where you lived in Missouri.
But that is not what we are expecting this time. It was prolonged exposure to the cold that took out the mushrooms in 2007. Here the historical data on the cold spell based on Columbia temperature recordings kept in the Farmer's Almanac.
Sat April 7, 2007 -- low was 19, mean temp was 28.4
Sun April 8,2007 -- low was 19, mean temp was 32
You can see that back in 2007, the temp was below freezing for almost 48 hours. That is what you have to worry about, temps below freezing that last longer than 12-24 hours. As long as the night time lows rebound above freezing during the day, everything should be fine. So, based on the forecast, actually, this cold spell has more chance of prolonging the season than ending it.
With this in mind, I welcome the upcoming weather. What we want is a long, cool, wet spring. In my opinion, only three things shorten a season:
- A prolonged freeze once they have already come up.
- Prolonged warmth (2 days in a row with air temps above 80). This causes them to grow big, fall over, and begin to rot from bacteria and mold.
- No rain - no matter what the temp is, if there is no moisture the morels will dry up.