This spring in Indiana has demonstrated just how much heat units, often measured as growing degree days to track crop growth and insect development, really mean to the development of crops. Normally there may be no GDDs accumulate in March. That's because the temperature has to average above 50 degrees F for any to be recorded. This March there were up to 200 GDDs recorded in some places.
Except for the few people who already had corn or soybeans in the ground, it may not have meant much crop-wise. However, it threw the spring development of plants about two weeks or more ahead of schedule. That may come back to haunt some aspects of agriculture later, depending upon what happens this week and over the next couple of weeks. But for some crops and plants, the genie is already out of the bottle for this year.
Bill Doig found mushrooms about two weeks ahead of schedule this year. The Johnson County Extension ag educator likes to hunt mushrooms, and turned it into an educational program and learning experience for hundreds of people who attended his programs in central Indiana. Normally, he finds the first ones in central Indiana in early April. Mushroom development is controlled by spoil temperature in combination with daytime highs and nighttime lows as far as air temperature goes, he notes.
"Typically when redbuds bloom mushrooms begin to appear," he says. "Then dogwoods bloom about the middle of the mushroom season. When you see certain wildflowers bloom, such as jack-in-the-pulpits, you're getting toward the end of the mushroom season."
This spring has been dramatic proof of what effect temperatures have upon plant development, regardless of the calendar, Doig says.
The recent cold weather may extend the mushroom season, but this could be the last week to find mushrooms this year in central Indiana,. He notes. The season begins and ends earlier for mushroom hunters in southern Indiana, and begins and ends alter in northern Indiana, compared to central Indiana.
If temperatures return to the 70's and some showers fall, the last mushrooms of the season may emerge, he notes.